i
EVALUATION OF THE EFFECTIVENESS OF WESTERN
STATES’ AQUATIC INVASIVE SPECIES PUBLIC
AWARENESS CAMPAIGNS FOR ELICITING DESIRED
PREVENTION BEHAVIORS
FINAL REPORT
August 2022
Gerard Kyle, PhD
Department of Rangeland, Wildlife & Fisheries Management
Quinn Linford
Daniel Pilgreen
Trang Le
Department of Recreation, Park & Tourism Sciences
Richard Woodward
Department of Agricultural Economics
Contact:
Gerard Kyle
Department of Rangeland, Wildlife & Fisheries Management
Texas A&M University
2138 TAMU
College Station TX 77843-2261
Email: gkyle@tamu.edu
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CONTENTS
Acknowledgements .................................................................................................................................. iii
LIST OF TABLES ................................................................................................................................ IV
EXECUTIVE SUMMARY ...................................................................................................................... V
1.0 INTRODUCTION ............................................................................................................................1
2.0 BACKGROUND ..............................................................................................................................2
3.0 STUDY DESIGN AND METHOD .......................................................................................................4
3.1 Key Informant Interviews .................................................................................................................... 4
3.2 Survey Questionnaire .......................................................................................................................... 4
3.3 Data Collection .................................................................................................................................... 9
3.4 Message Experiment - Manipulation Check ..................................................................................... 12
4.0 SAMPLE PROFILE ........................................................................................................................ 14
5.0 STUDY FINDINGS ........................................................................................................................ 19
5.1 Familiarity with Clean, Drain, Dry ..................................................................................................... 19
5.2 Awareness and Concern over Aquatic Invasive Species ................................................................... 20
5.3 Exposure to Aquatic Invasive Species Messaging ............................................................................. 21
5.4 Trust in Information Source .............................................................................................................. 22
5.5 Perceived Effectiveness of Clean, Drain, Dry Messaging .................................................................. 23
5.6 Message Experiment – Encouraging Clean, Drain, Dry ..................................................................... 25
5.7 Message Experiment – Perceived Severity of Aquatic Invasive Species ........................................... 27
5.8 Message Experiment – Message Influence on Clean, Drain, Dry ..................................................... 28
5.9 Frequency of Undertaking Clean, Drain, Dry .................................................................................... 31
5.10 Perceived Effectiveness of Clean, Drain, Dry .................................................................................. 32
5.11 Perceived Difficulty of Undertaking Clean, Drain, Dry .................................................................... 33
5.12 Perception of Other Boaters’ Clean, Drain, Dry Behavior ............................................................... 34
5.13 Expectation from Others to undertake Clean, Drian, Dry Behavior ............................................... 35
5.14 Perceived Obligation to Engage in Clean, Drain, Dry Behavior ....................................................... 36
5.15 Constraints to Undertaking Clean, Drain, Dry Behavior ................................................................. 37
5.16 Trust in State to Manage Aquatic Invasive Species ........................................................................ 38
5.17 Comparisons of Select Variable by Boater Characteristics ............................................................. 39
5.18 Message Treatment Follow-up Analyses ........................................................................................ 45
6.0 DISCUSSION & RECOMMENDATIONS .......................................................................................... 47
7.0 REFERENCES ............................................................................................................................... 53
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Acknowledgements
This research was funded by a U.S. Fish and Wildlife Service Quagga Zebra Mussel Action Plan
implementation grant via the Invasive Species Action network (# 21-001A). We would also like to extend
our appreciation to Monica McGarrity and the members of the Education and Outreach Committee for
the Western Regional Panel on Aquatic Nuisance Species for their guidance and thoughtful feedback
throughout the conduct of this work.
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LIST OF TABLES
Table 1. Message Treatments ....................................................................................................................... 6
Table 2. Solicitation, Response, and Questionnaire Completion ................................................................ 10
Table 3. Manipulation Check Questions ..................................................................................................... 12
Table 4. Age Categories............................................................................................................................... 14
Table 5. Gender ........................................................................................................................................... 14
Table 6. Race ............................................................................................................................................... 14
Table 7. Education ....................................................................................................................................... 15
Table 8. Household Income ........................................................................................................................ 15
Table 9. Primary Boating State/Province .................................................................................................... 16
Table 10. State/Province of Primary Residence .......................................................................................... 17
Table 11. Watercraft Ownership................................................................................................................. 17
Table 12. Activity Preferences .................................................................................................................... 18
Table 13. Days Boating by Season............................................................................................................... 18
Table 14. Primary Waterbody ..................................................................................................................... 18
Table 15. Familiarity with AIS ...................................................................................................................... 19
Table 16. Attitudes Toward AIS ................................................................................................................... 20
Table 17. Information Source ..................................................................................................................... 21
Table 18. Trust in Source of Information about AIS .................................................................................... 22
Table 19. Perceived Effectiveness of Information Source .......................................................................... 24
Table 20. Message Effect on Clean Drain Dry ............................................................................................. 26
Table 21. Perceived Problem of AIS in State ............................................................................................... 27
Table 22. Message Influence on Clean, Drain, Dry Behavior ...................................................................... 29
Table 23. Statistical Variation Among Message Treatments ...................................................................... 30
Table 24. Frequency of Undertaking Clean, Drain, Dry .............................................................................. 31
Table 25. Effectiveness of Clean, Drain, Dry ............................................................................................... 32
Table 26. Perceived Difficulty of Clean, Drain, Dry ..................................................................................... 33
Table 27. Perception of Other Boaters’ Clean, Drain, Dry .......................................................................... 34
Table 28. Perception of Other Boaters’ Expectation of Me to Engage in Clean, Drain, Dry ....................... 35
Table 29. Personal Obligations to Engage in Clean, Drain, Dry .................................................................. 36
Table 30. Constraints to Engaging in Clean, Drain, Dry .............................................................................. 37
Table 31. Individual Behaviors - Constraints to Engaging in Clean, Drain, Dry ........................................... 37
Table 32. Trust in State to Manage AIS ....................................................................................................... 38
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EXECUTIVE SUMMARY
Study Purpose
The overarching goal of this project was to collect and analyze data that would ultimately enhance the
long-term success of aquatic invasive species (AIS) prevention outreach campaigns across Western
Regional Panel (WRP) member states and member organizations by analyzing the effectiveness of
current and potential messaging and delivery methods to elicit desired behavior change from specific
demographics. However, the applicability of the results of this effort are not limited to the project’s
geographical area.
Design
• Thirty-one key informant interviews were conducted in the fall of 2021. Most informants had in
excess of 20 years of boating experience and occupied a professional or voluntary role in the
management of AIS in their communities. Analyses of the interview data provided some insight on
different AIS message content, message placement, and mode of delivery. These findings were
integrated into our survey questionnaire.
1. The survey questionnaire was comprised of series of items that explored an array of issues related
to boaters’ perceptions and actions related to AIS. It also included a messaging experiment where
respondents were assigned to one of 20 message treatments and requested to indicate the
message’s effectiveness for encouraging Clean, Drain, Dry. The survey questionnaire took
approximately 25 minutes to complete.
2. Three broad approaches were employed to contact potential respondents; 1) Texas A&M University
sending emailing solicitations to potential respondents in databases provided by participating states;
2) Participating states distributing a web-link to the questionnaire hosted by Texas A&M University
to their registered boater or licensed angler databases; and 3) states posting the web-link to the
questionnaire on their agency website.
3. The varied methods yielded 3,900 fully completed questionnaires.
Sample Profile
The survey sample was relatively homogenous and comprised mostly of White, older men (M=58 years),
residing in households with annual incomes in excess of $100,000. These demographics are consistent
with other surveys of registered boaters.
Findings
• Familiarity with AIS - Respondents reported being broadly aware of AIS and the need to Clean,
Drain, Dry. They were less familiar with specific species present in their state and locations
(waterbodies) of where they have been detected.
• Frequency of Clean, Drain, Dry - Respondents reported that they regularly Clean, Drain, and Dry their
boats prior to entering another waterbody. They are less inclined to wash their watercraft with a
pressure washer or hot water.
• Perceived Effectiveness of Clean, Drain, Dry - Actions related to cleaning, draining, and drying
respondents’ watercraft were considered most effective. Considered to be less effective was
washing watercraft with a pressure washer or hot water before entering another waterbody.
• Constraints to Clean, Drain, Dry - Twenty-five percent of respondents indicated facing some form of
a constraint to undertaking Clean, Drain, Dry. The absence of cleaning stations, crowding at boat
ramps, and skepticism over other boaters’ undertaking Clean, Drain, Dry were the most cited
reasons constraining their behavior.
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• Information about AIS - Boat ramp signage, state agency websites, and inspection station personnel
were the most commonly cited sources of information about AIS.
• Trust in Information Providers - State agency websites, boat ramp signage, inspection stations, and
conservation organizations were the most trusted sources of AIS information.
• Perceived Effectiveness of Information about AIS and Clean, Drain, Dry - Respondents were
requested to indicate which of the listed sources of information would be most effective at; a)
preventing the spread of AIS, b) encouraging Clean, Drain, Dry, and c) reaching the population of
boaters across the state. Boat ramp signage and state agency websites were considered to be most
effective for accomplishing all three outcomes. Alternately, while inspection stations were
considered to be effective for encouraging Clean, Drain, Dry, and preventing the spread of AIS, they
were somewhat limited in their ability to reach the population of boaters.
• Messaging Experiment to Encourage Clean, Drain, Dry - While no single treatment message was
statistically superior at encouraging Clean, Drain, Dry, seven messages scored highest. Their means
of 3.4 (on a 5-point scale) or greater indicate that respondents felt the messages would be
moderately to quite effective at increasing boaters’ Clean, Drain, Dry behavior. The messages were
designed around themes related to:
• Militaristic, nativist, protective, and science-based metaphors;
• Injunctive norms (i.e., encouraging the belief that other boaters expect them to Clean, Drain,
Dry); and
• Economic losses and ecological gains.
Messages that respondents considered least effective were focused on specific identities (i.e.,
hunter, boater, paddler) and a combination of descriptive and injunctive norms (i.e., other boaters’
expectation of them and the suggestion that other boaters conduct Clean, Drain, Dry).
Follow-up analyses exploring variation among select groups on the most effective message revealed
little variation.
Discussion/Conclusion
• Age was associated with awareness and knowledge of AIS and Clean, Drain, Dry behavior with older
boaters scoring higher. Messaging toward a younger cohort ought to occur early in their boating
careers. Beyond the most popular sources (i.e., boat ramps, state agency websites, and inspection
stations), these messages could be delivered with boat registration and fishing license renewals.
• Familiarity with AIS (prior to taking survey) was linked to the extent to which respondents interacted
with the resource (e.g., houseboat owners, tournament anglers, avid boaters). Those least familiar
with AIS reported (e.g., pontoon and sailboat owners, paddlers, hunters) less concern over AIS and a
lower likelihood of implementing Clean, Drain, Dry. Those most actively interacting with the
resource will likely encounter AIS messaging through the most popular sources of information (boat
ramp kiosks, state agency websites, inspection stations), whereas accessing infrequent boaters will
be an ongoing challenge. Point of sale for non-motorized watercraft (e.g., decals placed on the
watercraft) and hunting licenses provides one opportunity for agency contact.
• In terms of AIS information to which respondents had been previously exposed:
o Most common sources were boat ramp kiosks, followed by the state’s agency website, and then
inspection station personnel. For these information sources, respondents indicated that their
state’s agency websites were most trusted, followed by boat ramp kiosks, and then state
inspection personnel. AIS information should be easily accessible on agency websites. Given
their broad coverage and, importantly, boaters’ trust in the state to provide up to date
information about AIS, access to this information on agency websites should feature
prominently.
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o Younger (18-25) respondents were more likely to trust conservation organizations. Conservation
organizations provide an opportunity to develop strategic partners that can help amplify agency
efforts through social media, their agency websites, and through members’ social networks.
Regular active engagement with these partners would also assist in providing up to date
information.
o Similar to respondents’ exposure and trust, boat ramp signage, state agency websites, and state
inspection personnel were considered most effective for preventing the spread of AIS,
encouraging Clean, Drain, Dry, and reaching the population of boaters. Residents of states
utilizing inspection stations (e.g., California, Utah, Nevada) expressed greater trust in the
information provided by inspection station personnel, considered the information more
effective at preventing the spread of AIS, and more effective at encouraging Clean, Drain, Dry.
While the coverage of the information provided by inspection station personnel is
geographically limited, it is clearly a useful tool and one that warrants consideration/adoption.
• In terms of the messaging experiment:
o Overall, respondents considered the identity frames least effective compared to other frames at
encouraging Clean, Drain, Dry.
o Statistically, there was no significant variation among message treatments – all moderately
effective at encouraging Clean, Drain, Dry. Seven messages, however, were somewhat superior.
For future messaging efforts, agencies should consider elements of each message or in
combination when designing persuasive appeals. These include:
o All metaphor themes preformed comparatively well compared to other message
treatments. The science metaphor was the strongest performer in terms of
respondents’ reported effectiveness for encouraging Clean, Drain, Dry.
o Framing the impact of AIS on aquatic ecosystems (i.e., health in the absence of AIS) and
the state’s economic health (i.e., detriment with their presence) is compelling.
o Unlike the descriptive norm, the injunctive norm message attempts to instill a personal
obligation that rests on the perception of others’ expectations.
• Respondents indicated that they almost always engaged in cleaning and draining behaviors. They
indicated being less likely, however, to wash their boat with a pressure washer or hot water. Not all
boaters will have access to a pressure washer and washing watercraft with hot water is likely
perceived to be cumbersome. Cleaning stations with pressure washers or hot water would help to
address this issue.
• The installation of cleaning stations with clearly visible messaging kiosks would help negate the
perception that few undertake Clean, Drain, Dry by providing evidence of others taking action. The
more boaters are seen to be engaging in these actions, the more normative the behavior becomes.
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1.0 INTRODUCTION
The overarching goal of this project was to collect and analyze data that would ultimately enhance the
long-term success of aquatic invasive species (AIS) prevention outreach campaigns across Western
Regional Panel (WRP) member states and member organizations by analyzing the effectiveness of
current and potential messaging and delivery methods to elicit desired behavior change from specific
demographics. However, the applicability of the results of this effort are not limited to the project’s
geographical area.
Objective 1: Evaluate and quantify the effectiveness of WRP states’ campaign messaging, current and
potential, alone or in combination, in eliciting the desired AIS prevention behavior among boaters (e.g.,
pull drain plugs, do not launch for a specific period of time, remove vegetation, don’t dump bait, etc.)
for specific boating and boater demographics. The focus will be placed on high-risk recreational user
groups, in accordance with guidance from the WRP Education Outreach Committee (EOC). Past, current,
and future behaviors were evaluated.
Objective 2: Evaluate and quantify the effectiveness of delivery methods currently used–or that could
potentially be used–by WRP states to elicit desired AIS prevention behaviors for specific boating and
boater demographics.
Objective 3: Provide a summary report/publication on the effectiveness of current and past WRP states’
public outreach campaigns’ messaging and delivery methods and recommendations on how to most
effectively tailor campaigns to elicit specific AIS prevention behaviors overall and for specific
recreational user groups and demographics which includes:
• analysis of the effectiveness of WRP states’ messaging
• analysis of the effectiveness of implemented delivery methods
• recommendations on specific messaging that may be most effective
• recommendations on delivery methods that may be most effective for different demographics
• recommendations on other important considerations on how to effectively elicit specific AIS
prevention behaviors
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2.0 BACKGROUND
Humans have had enormous impacts on earth and its biodiversity and many of these effects are global.
Lakes and streams are particularly prone to species loss (Ricciardi & Rasmussen, 1999), with the greatest
threats coming from land use changes and exotic invasive species (“biotic exchange”, Sala et al., 2000).
Humans have been particularly effective in breaking down biogeographic barriers through long-distance
trade, intentionally introducing some species and carrying others as hitchhikers (Kolar & Lodge, 2000).
The result has been a translocation of numerous freshwater species (Hulme, 2009). Although most
introduced species fail to establish and spread (Williamson, 1996), many freshwater species have
become invasive and some have caused widespread environmental effects and economic harm
(Pimentel et al., 2005).
Freshwater ecosystems have greater biodiversity per surface area than marine and terrestrial
ecosystems (Dudgeon et al., 2006; Balian et al., 2008). Freshwater ecosystems also play an active role in
nutrient and water cycling (Wetzel, 2001), which translate into goods and services for human societies.
At the same time, freshwater ecosystems have been deeply transformed by invasive species from a wide
variety of taxonomic groups (Strayer, 2010; Simberloff et al., 2013). It is thus vital to understand the
factors that govern the introduction, spread, and subsequent impacts of invasive species in these
ecosystems.
Recreational boating can significantly contribute to the rapid spread of AIS by unintentionally
transporting species attached to hulls, props, and other submerged components attached to the
watercraft, as well boat live wells or any other water-bearing compartments. Boaters often travel long
distances for recreation in different freshwater bodies and can be a significant vector for spreading AIS
between inland waters (Johnson et al., 2001; Robertson et al., 2020; Rothlisberger et al., 2010). This fact
highlights the crucial role boaters’ preventive behavior can play in controlling and reducing AIS high
economic and ecological impacts. Cleaning, draining, and drying watercraft is recognized as the key
desired boater behavior for AIS spread prevention and “Clean, Drain, Dry” is a central message in AIS
outreach at a national scale.
Despite the significance of their role in controlling and managing the spread of AIS, our understanding of
boaters’ preventive behavior and the impact of possible interventions to alter behavior is, in large part,
restricted to insights gleaned from studies conducted in the Eastern and Great Lakes states. Among
these studies, several have explored the effectiveness of various outreach and communication
strategies. For instance, Wallen and Kyle (2018) found that regulation-framed messages emphasizing the
law and the possibility of fines outperformed messages referring to the norms of compliance with Clean,
Drain, Dry. The results from Sharp et al.'s (2017) study also revealed the importance of educational
programs tailored to specific recreational uses and recreational settings in compliance with preventive
measures. Moreover, Witzling et al. (2016) and Witzling et al. (2015) evaluated the effectiveness of
different communication channels and found that signs posted at boat ramps, interpersonal
communications, information provided by lake associations, and direct communication between natural
resource managers and boaters can all be effective to varying degrees when messaging is tailored to
different groups of boaters. These findings highlight the need for communication strategies to be multi-
modal in terms of the distribution of AIS information to improve the likelihood of message exposure and
targeted toward different boating and aquatic recreation use groups.
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Another line of research has revealed the relationship between socio-psychological factors and boater
intentions, and preventive pro-environmental behavior. These studies have shown psychological drivers
such as norms (personal and social), the ascription of responsibility, a concern for the environment and
threats to its health, and value orientations can all shape boaters’ willingness to engage in pro-
environmental behavior that mitigates the threat of AIS (Kemp et al., 2017; Pradhananga et al., 2015;
van Riper et al., 2019). Similarly, those who felt greater responsibility and a moral obligation to prevent
the spread of ANS reported engaging in preventive measures more often (Beardmore, 2015; Mayer et
al., 2015; Seekamp et al., 2016). Also, the more likely boaters were to express concern for
environmental protection and an understanding of the risks posed by the spread of AIS, the more likely
they were to report adopting preventive action (Connelly et al., 2016; Pavloski et al., 2019; Pradhananga
et al., 2015). Moreover, boaters’ perception of what their peers do and significant others expect them to
do influences their behavior (Connelly et al., 2016; Wallen & Kyle, 2018; Witzling et al., 2015). Other
studies have also investigated the relationship between the public’s awareness and knowledge of ANS
and their behavior. The findings, generally, demonstrate that residents, especially those who participate
in water-based recreation, are supportive of actions to minimize the effects of AIS when they are aware
of the negative consequences (e.g., Eiswerth et al., 2011; Fouts et al., 2017; Sharp et al., 2017).
There is research, however, that reveals a mismatch between boaters’ AIS awareness and support for
preventive measures and their willingness to adopt mitigation behavior (Cole et al., 2016; Connelly et
al., 2016; Mueting & Gerstenberger, 2011). For instance, Cole et al. (2016) found that raising awareness
and knowledge is a necessary but insufficient condition for the adoption of ANS prevention behaviors.
Their results illustrate that awareness of AIS spread and its impact on aquatic ecosystems does not
necessarily relate to an agency’s investment in outreach (Cole et al., 2016). Similarly, Connelly et al.
(2016) and Ventura et al. (2017) found that despite high awareness and stated support, boaters were
less frequently conducting difficult preventive actions, such as drying and disinfecting, rinsing equipment
with hot water, or using high-pressure washing. These findings highlight often reported gaps between
individuals’ awareness of environmental issues and appropriate action. These knowledge/awareness-
action gaps necessitate outreach efforts focusing on strategies that facilitate behavior and remove
barriers (Kollmuss & Agyeman, 2002; Lorenzoni et al., 2007; Steg et al., 2014).
Last, research on the barriers to engagement in pro-environmental behavior has also revealed that
regardless of environmental concern, they have the potential to significantly constrain intent and action
(Cleveland et al., 2020; Moghimehfar & Halpenny, 2016; Tanner, 1999). Broadly, two categories of
constraints to pro-environmental action have been identified in the literature; subjective and objective
(Tanner, 1999). Findings illustrate that objective constraints, such as time, the availability of facilities,
space limitations, cost, and convenience hinder pro-environmental action (Lorenzoni et al., 2007;
Moghimehfar & Halpenny, 2016). However, there is evidence suggesting that subjectively perceived
barriers (e.g., perceived costliness, perceived ineffectiveness) are a more compelling obstacle for
adopting pro-environmental action (Cleveland et al., 2020; Steg et al., 2014). In the context of
preventing the spread of ANS, boater misconceptions on subjectively defined constraints related to
perceived cost, effort, and effectiveness can negatively impact their willingness to adopt mitigation
measures (Connelly et al., 2016; Ventura et al., 2017).
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3.0 STUDY DESIGN AND METHOD
3.1 Key Informant Interviews
Thirty-one key informant interviews were conducted with boaters from Arkansas (3), California (4),
Kansas (3), North Dakota (1), Nevada (2), South Dakota (2), Texas (4), Utah (8) and Washington (4). State
AIS coordinators provided informants’ contact information. Key informants are “particularly
knowledgeable and articulate – people whose insights can prove particularly useful in helping the
observer understand what is happening” (Patton, 1990). The key informant interviews were conducted
to ensure that we were not missing content that would be crucial in the development of our survey
questionnaire. The interview guide is provided in Appendix A1.
Most informants had in excess of 20 years of boating experience and occupied a professional or
voluntary role in the management of AIS in their communities. Analyses of the interview data provided
some insight on different AIS message content, message placement, and mode of delivery. These
findings were integrated into our survey questionnaire.
3.2 Survey Questionnaire
The survey questionnaire was comprised of series of items that explored an array of issues related to
boaters’ perceptions and actions related to AIS and as arranged in six sections (see Appendix A3):
4. Watercraft ownership and use history;
5. Knowledge and awareness of aquatic invasive species;
6. AIS messaging awareness and preferences;
7. AIS messaging experiment;
8. Clean, drain, dry behavior, perceived effectiveness, perceived difficulty, and perceived
prevalence; and
9. Socio-demographic characteristics.
For the AIS messaging experiment, respondents were presented with one of 20 messages and asked a
series of questions about their perception on whether or not the image would impact Clean, Drain Dry
behavior (See Table 1 and Appendix A3). The message treatments were structured around eight themes
all focused on promoting Clean, Drain, Dry behavior plus a control:
1. A control message with a basic Clean, Drain, Dry statement.
2. The control in addition to the “Stop Aquatic Hitchhikers” branding.
3. The control in addition to statement about Clean, Drain, Dry being required by law.
4. The control in addition to four treatments focused on respondents’ identity as a;
a. Boater,
b. Paddler,
c. Hunter, and
d. Angler.
5. The control in addition to four treatments examining ecological and economic gains and losses.
6. The control in addition to three treatments examining norms associated with Clean, Drain, Dry
behavior;
a. Injunctive – Individual perceptions of what boaters ought to do,
b. Descriptive – Individual perceptions of what other boaters are doing, and
c. Combination of injunctive and descriptive norm messaging.
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7. The control in addition to four metaphor-themed messages focused on;
a. Science,
b. Protection/nurturing,
c. Nativist, and
d. Militaristic.
8. The control in addition to a messaging informing boaters they are entering a lake with AIS.
9. The control in addition to a message indicating boaters need to Clean, Drain, Dry their
watercraft after leaving every lake, every time.
The treatments focused on identity were drawn from the work of Fielding and associates’ work on social
identity and its association conservation-related behaviors (Fielding & Hornsey, 2016; Schultz & Fielding,
2014; Unsworth & Fielding, 2014). This work reveals the extent to which identity salience and the
norms associated with the identity gird pro-environmental behavior. The environment and economic
gain/loss scenarios were drawn from Degolia, et al.’s (2019) related to wild pig management. Their work
revealed that messages framed in terms of environmental outcomes, as opposed to economic, elicited
more support for AIS management among a sample of California residents. Also, messages referencing
economic and environmental loss drove stronger support for invasive species management compared to
messages referencing gain. Normative message frames were drawn from the work of Wallen and Kyle
(2018). Metaphor themed frames were drawn from Shaw, Campbell, and Radler (2021). These
metaphors touched upon themes related to; a) science with objective, fact-based information, b) the
protection of nature with a nurturing statement related to protecting the environment, c) non-nativist
with reference to alien species, and d) militaristic with reference to battles against invasives.
6
Table 1. Message Treatments
Treatment
Theme
Message
Image
Footer
1
Baseline/Control
Clean, Drain, Dry
Different
boater types
2
Stop aquatic
hitchhikers branding
Stop aquatic hitchikers brand logo
Logo
Clean, Drain, Dry
3
Legal
IT’S THE LAW.
CLEAN, DRAIN, DRY YOUR BOAT
Different
boater types
Clean, Drain, Dry
4
Identity
BOATERS - DO YOUR PART
CLEAN, DRAIN, DRY YOUR BOAT
Motorboat
Clean, Drain, Dry
5
PADDLERS - DO YOUR PART
CLEAN, DRAIN, DRY YOUR BOAT
Paddlers
Clean, Drain, Dry
6
HUNTERS - DO YOUR PART
CLEAN, DRAIN, DRY YOUR BOAT
Hunters
Clean, Drain, Dry
7
ANGLERS - DO YOUR PART
CLEAN, DRAIN, DRY YOUR BOAT
Anglers
Clean, Drain, Dry
Loss/Gain
8
Ecological Loss
PROTECT YOUR WATERS.
CLEAN, DRAIN, DRY.
Our aquatic ecosystems will
suffer tremendously
Different
boater types
Clean, Drain, Dry
9
Ecological Gain
PROTECT YOUR WATERS.
CLEAN, DRAIN, DRY.
Our aquatic ecosystems will
benefit tremendously
Different
boater types
Clean, Drain, Dry
10
Economic Loss
PROTECT YOUR WATERS.
CLEAN, DRAIN, DRY.
It will cost our state (YOU) $
millions
Different
boater types
Clean, Drain, Dry
11
Economic Gain
PROTECT YOUR WATERS.
CLEAN, DRAIN, DRY.
It saves our state (YOU) $ millions
Different
boater types
Clean, Drain, Dry
7
Table 1 (continued). Message Treatments
Treatment
Theme
Message
Image
Footer
Norms
12
Descriptive
PROTECT YOUR WATERS.
The MAJORITY of the state’s
boaters CLEAN, DRAIN, DRY their
boats
Different
boater types
Clean, Drain, Dry
13
Injunctive
PROTECT YOUR WATERS.
the state’s boaters EXPECT you to
CLEAN, DRAIN, DRY your boat
Different
boater types
Clean, Drain, Dry
14
Descriptive/injunctive
PROTECT YOUR WATERS.
The MAJORITY of the state’s
boaters EXPECT you to CLEAN,
DRAIN, DRY your boat
Different
boater types
Clean, Drain, Dry
Metaphors
15
Science
PREVENT THE SPREAD OF
AQUATIC INVASIVE SPECIES.
Aquatic invasive species are
present in our state’s lakes and
rivers and can severely impact
these ecosystems
Different
boater types
Clean, Drain, Dry
16
Protective/Nurturing
HELP PROTECT OUR WATERS.
Aquatic invasive species harm our
lakes and rivers.
Different
boater types
Clean, Drain, Dry
17
Nativist
NOT NATIVE, NOT WELCOME
Keep aquatic invasive species out
of our state’s lakes and rivers
Different
boater types
Clean, Drain, Dry
18
Militaristic
STOP THE INVASION OF AQUATIC
INVASIVE SPECIES
Help fight the battle again aquatic
invasive species
Different
boater types
Clean, Drain, Dry
8
Table 1 (continued). Message Treatments
Treatment
Theme
Message
Image
Footer
19
Entering
You are entering a lake that has
AQUATIC INVASIVE SPECIES.
Be sure you CLEAN, DRAIN, DRY
before re-entering another
waterbody
Different
boater types
Clean, Drain, Dry
20
Every lake, every
time
Every lake, every time
Different
boater types
Clean, Drain, Dry
9
3.3 Data Collection
Respondents’ access to the questionnaire utilized multiple solicitation modes. The different methods of
solicitation are displayed in Table 2 below. Three broad approaches were employed:
1. For solicitations management by TAMU, respondents were sent an email with an individualized
URL. Two additional email reminders/thank you notes were sent four days apart.
2. For agencies electing to distribute a URL to their registered boaters of licensed anglers, multiple
approaches were employed; 1) email a single URL and email a follow-up thank you reminder, 2)
post a weblink on their agency website, and 3) promote the URL on the agency’s social media
(Facebook, Twitter).
3. States posted a URL weblink on their agency website.
Collectively, 8,135 recipients of the solicitation initiated the questionnaire. The first question
respondents encountered asked if they had boated in freshwater in the previous 12 months. Only those
answering “yes” proceeded with the questionnaire; 6,393 responded “yes”. Of these, 3,900 completed
all questions. For our AIS messaging experiment, Qualtrics® randomly assigned each respondent to one
of the 20 message treatments. Responses to each treatment ranged between 201 to 226 responses.
10
Table 2. Solicitation, Response, and Questionnaire Completion
State/Province
Email Invitation Sent by TAMU
Email Invitation Sent by State
Weblink Posted on
State Agency Website
Sent
a
Initiated
b
Complete
c
Sent
a
Initiated
b
Complete
c
Initiated
Complete
Alaska
1
126,082
2,332
573
Arizona
2
13
8
California
3
464
332
Colorado
4
48
39
Hawaii
5
4
3
Idaho
6
24
16
Kansas
7
10,000
1,313
942
Montana
8
400
24
16
Nevada
9
100
97
Nebraska
10
2
2
New Mexico
11
1
1
North Dakota
12
4
2
Oklahoma
13
10,000
203
65
Oregon
14
10,000
1,007
548
South Dakota
15
5
3
Texas
16
10,000
939
527
Utah
17
8,000
1,590
1,040
Washington
18
10,000
52
47
Wyoming
19
10
9
11
a
Weblink sent to respondents.
b
Respondents clicking on weblink to commence completing the questionnaire.
c
Full completion of the questionnaire.
1
Email sent to hunting and fishing license holders purchased in 2019 and 2020.
2
Did not post weblink. Respondents reported residing outside of AZ but boat in AZ.
3
State weblink was included in an “angler update” promotional/information email distributed to
licensed anglers in additional to sharing on the Division of Boating and Waterway’s Facebook Page.
4
Weblink on agency website promoted through Colorado Department of Natural Resources social
media.
5
Twelve boaters were approached at a fishing club on Wahiawa Reservoir.
6
Link placed on websites for Idaho Parks and Recreation Department, Idaho Department of Agriculture,
and Invasive Species of Idaho.
7
An email invitation and additional reminder was sent to a random sample of registered boaters.
8
Three email invitations sent four days apart.
9
Weblink on agency website promoted through Nevada Department of Wildlife social media. Two email
solicitations sent to motorized and non-motorized boaters who had purchased an AIS decal.
10
Did not participate.
11
Did not participate.
12
Weblink posted on agency website.
13
Three email invitations sent four days apart.
14
Three email invitations sent four days apart.
15
Weblink posted on agency website.
16
Three email invitations sent four days apart.
17
Link distributed by Utah Division of Wildlife Resources. Link also promoted on agency Facebook page
and distributed with flyers.
18
Email invitation sent to licensed anglers.
19
Link placed on Wyoming Game and Fish Department website.
12
3.4 Message Experiment - Manipulation Check
For our AIS messaging experiment, to ensure respondents had read and accurately processed the content of each image, respondents were
requested to answer two questions;
1. What does this message tell you about Clean, Drain, Dry behaviors? and
2. What do you think is the intent of this message?
Responses to the first question were tailored around the content of each image/message and are displayed in Table 3. The response choice for
the question was a dichotomous “yes/no” with “yes” being the correct answer. For the second question, respondents were again requested to
answer “yes/no” to the question with “yes” also being the correct answer. If respondents answered “no” to either question, they were removed
from the analyses. Four hundred and six respondents were removed from the analyses.
Table 3. Manipulation Check Questions
Message
What does this message tell you about Clean, Drain, Dry behaviors?
a
What do you think is the intent of this
message?
a
1
[state] boaters should clean, drain, and dry their boats and equipment before
entering another waterbody.
To encourage, clean, drain dry behaviors
among [state] boaters.
2
To prevent the spread of aquatic invasive and stop aquatic hitchhikers, [state]
boaters should clean, drain, and dry their watercraft and equipment before entering
another waterbody.
To encourage, clean, drain dry behaviors
among [state] boaters.
3
Cleaning, draining, and drying your watercraft and equipment is required by [state]
law.
To encourage, clean, drain dry behaviors
among [state] boaters.
4
It is a boater’s responsibility to clean, drain, and dry their watercraft and equipment
before entering another waterbody.
To encourage, clean, drain dry behaviors
among [state] boaters.
5
It is a paddler’s responsibility to clean, drain, and dry their watercraft and
equipment before entering another waterbody.
To encourage, clean, drain dry behaviors
among [state] boaters.
6
It is a hunter’s responsibility to clean, drain, and dry their watercraft and equipment
before entering another waterbody.
To encourage, clean, drain dry behaviors
among [state] boaters.
7
It is an angler’s responsibility to clean, drain, and dry their watercraft and
equipment before entering another waterbody.
To encourage, clean, drain dry behaviors
among [state] boaters.
13
Table 3 (continued). Manipulation Check Questions
Message
What does this message tell you about Clean, Drain, Dry behaviors?
a
What do you think is the intent of this
message?
a
8
The [state]’s aquatic ecosystems will suffer if [state] boaters do not clean, drain, and
dry their watercraft and equipment before entering another waterbody.
To encourage, clean, drain dry behaviors
among [state] boaters.
9
The [state]’s aquatic ecosystems will benefit from [state] boaters cleaning, draining,
and drying their watercraft and equipment before entering another waterbody.
To encourage, clean, drain dry behaviors
among [state] boaters.
10
If [state] boaters fail to adopt clean, drain, and dry behaviors it will cost the state
millions of dollars to mitigate damage from aquatic invasive species
To encourage, clean, drain dry behaviors
among [state] boaters.
11
If [state] boaters fail to engage in clean, drain, and dry behaviors it will save the
state millions of dollars from having mitigate damage from aquatic invasive species
To encourage, clean, drain dry behaviors
among [state] boaters.
12
The majority of [state] boaters clean, drain, and dry their watercraft and equipment
before entering another waterbody.
To encourage, clean, drain dry behaviors
among [state] boaters.
13
[state] boaters expect you to clean, drain, and dry your boat and equipment before
entering another waterbody.
To encourage, clean, drain dry behaviors
among [state] boaters.
14
The majority of [state] boaters expect you to clean, drain, and dry your watercraft
and equipment before entering another waterbody.
To encourage, clean, drain dry behaviors
among [state] boaters.
15
Aquatic invasive species negatively impact [state] ecosystems and to prevent their
spread you should clean, drain, and dry your watercraft and equipment before
entering another waterbody.
To encourage, clean, drain dry behaviors
among [state] boaters.
16
To protect [state] waters, you should clean, drain, and dry your watercraft and
equipment before entering another waterbody.
To encourage, clean, drain dry behaviors
among [state] boaters.
17
Aquatic invasive species are neither native or welcome in [state] and you need to
clean, drain, and dry your watercraft and equipment before entering another
waterbody.
To encourage, clean, drain dry behaviors
among [state] boaters.
18
To prevent the invasion of aquatic invasive species in [state], you need to clean,
drain, and dry your watercraft and equipment before entering another waterbody.
To encourage, clean, drain dry behaviors
among [state] boaters.
19
You are about to enter a lake with aquatic invasive species and need to clean, drain,
and dry your watercraft and equipment before entering another waterbody.
To encourage, clean, drain dry behaviors
among [state] boaters.
20
You need to clean, drain, and dry your watercraft and equipment after leaving every
lake, every time.
To encourage, clean, drain dry behaviors
among [state] boaters.
a
Responses choice for both questions; Yes/No
14
4.0 SAMPLE PROFILE
Respondents were predominantly White (85.2%; Table 6), older (M=54.99) men (85.8%; Table 5). They
were relatively well educated with most having at least vocational school educational training or two-
year college (83.5%: Table 7) and residing in households with moderately high annual incomes (61.6%
earning > $100,000; Table 8).
Table 4. Age Categories
Table 5. Gender
Table 6. Race
n
%
18-25
28
.7
26-35
136
3.5
36-45
486
12.5
46-55
854
21.9
56-65
1256
32.2
66-75
923
23.7
> 75
217
5.6
Total
3900
100.0
n
%
Prefer not to answer
130
3.3
Female
420
10.8
Male
3346
85.8
Nonbinary
4
.1
Total
3896
100.0
n
%
Asian
42
1.0
Spanish/Hispanic/Latino
89
2.2
White
3447
85.2
American Indian/Alaska Native
102
2.5
Black/African American
24
.6
Native Hawaiian/Pacific Islander
18
.4
Middle Eastern
9
.2
Prefer not to Answer
226
5.6
Other
91
2.2
Total
4048
100.0
15
Table 7. Education
Table 8. Household Income
n
%
Less than high school
32
.8
High school graduate
611
15.7
Vocational/trade school Two-year college
1031
26.4
Four-year college
1366
35.0
Graduate degree
860
22.1
Total
3900
100.0
n
%
Prefer not to answer
131
3.4
Under $20,000
83
2.1
$20,000-$39,999
159
4.1
$40,000-$59,999
271
6.9
$60,000-79,999
421
10.8
$80,000-$99,999
434
11.1
$100,000-$119,999
530
13.6
$120,000-$139,999
381
9.8
$140,000-$159,999
334
8.6
$160,000 and above
1156
29.6
Total
4048
100.0
16
Respondents’ state of residence (Table 10) and primary boating state/province (Table 9) tracked along
response rates reflected in Table 2.
Table 9. Primary Boating State/Province
n
%
British Columbia
1
.0
Nunavut
1
.0
Alaska
505
12.9
Arizona
12
.3
Arkansas
4
.1
California
305
7.8
Colorado
20
.5
Hawaii
3
.1
Idaho
33
.8
Kansas
822
21.1
Minnesota
6
.2
Missouri
31
.8
Montana
21
.5
Nebraska
3
.1
Nevada
57
1.5
New Mexico
1
.0
North Dakota
1
.0
Oklahoma
75
1.9
Oregon
508
13.0
South Dakota
3
.1
Texas
484
12.4
Utah
950
24.4
Washington
39
1.0
Wyoming
15
.4
Total
3900
100.0
17
Table 10. State/Province of Primary Residence
The most commonly owned watercraft reported by respondents were ski/wakeboard boats (17.1%;
Table 11), followed by kayak/canoes (15.7%), other (13.6%), and bass boats (13.3%).
Table 11. Watercraft Ownership
n
%
Alberta
1
.0
Alaska
510
13.1
Arizona
8
.2
California
297
7.6
Colorado
34
.9
Hawaii
3
.1
Idaho
15
.4
Kansas
878
22.5
Montana
15
.4
Nebraska
2
.1
Nevada
72
1.8
New Mexico
1
.0
North Dakota
2
.1
Oklahoma
59
1.5
Oregon
501
12.8
South Dakota
2
.1
Texas
495
12.7
Utah
955
24.5
Washington
42
1.1
Wyoming
8
.2
Total
3900
100.0
n
%
Pontoon
455
7.2
Johnboat
555
8.8
Bass boat
836
13.3
Houseboat
132
2.1
Ski/Wake board
1080
17.1
Sailboat
122
1.9
Cabin Cruiser
181
2.9
Jet ski
435
6.9
Center console
336
5.3
Kayak/Canoe
988
15.7
Paddleboard
326
5.2
Other
855
13.6
Total
6301
100.0
18
Recreational fishing (44.0%; Table 12), pleasure cruising (27.7%), and wake sports (14.7%) were
respondents’ most favored activities.
Table 12. Activity Preferences
Summer (M=9.07 days; Table 13) was the most popular boating season.
Table 13. Days Boating by Season
Respondents indicated that lakes (77.5%; Table 14) were the freshwater waterbody they used most
often.
Table 14. Primary Waterbody
Respondents had extensive boating experience, reporting almost 19 years of boating experience
(M=18.76 years).
n
%
Recreational Fishing
2804
44.0
Tournament Fishing
168
2.6
Wake Sport
935
14.7
Pleasure Cruising
1729
27.2
Hunting
465
7.3
Other
267
4.2
Total
6368
100.0
Spring
Summer
Fall
Winter
M
4.93
9.07
5.40
1.30
SD
5.25
6.88
5.40
3.10
n
%
Lake
3022
77.5
River/Bayou
636
16.3
Offshore Ocean
30
.8
Inshore Bay
147
3.8
Private waterbody
65
1.7
Total
3900
100.0
19
5.0 STUDY FINDINGS
5.1 Familiarity with Clean, Drain, Dry
Respondents were most familiar with the with the need for boaters to engage in Clean, Drain, Dry before entering different waterbodies (item b,
M=4.58; Table 15). They were least familiar with the locations where AIS had been detected in their state (item d, M=3.54).
Table 15. Familiarity with AIS
Item
Not at all
familiar
Somewhat
familiar
Very
Familiar
M
SD
1
2
3
4
5
%
a. How familiar were you with aquatic invasive species
before taking this survey?
2.1 4.6 24.1 26.7 42.5 4.03 1.02
b. How familiar are you with the need for watercraft
users to clean their boats and equipment, drain all
water from the watercraft (e.g., bilges, ballasts), and
dry before entering another waterbody?
1.1 1.8 7.9 16.4 72.8 4.58 .80
c. How familiar are you with the aquatic invasive species
that have been detected in [state]?
4.0 8.8 27.3 26.2 33.6 3.77 1.13
d. How familiar are you with the locations (waterbodies)
where aquatic invasive species have been detected in
[state]?
7.8 11.3 28.7 23.3 28.8 3.54 1.23
e. How familiar are you with the problems caused by
aquatic invasive species in [state]?
2.2 4.6 19.6 26.7 46.9 4.12 1.02
20
5.2 Awareness and Concern over Aquatic Invasive Species
In terms of respondents’ awareness and concern over AIS (Table 16), most concern was expressed over the importance of preventing the spread
of aquatic invasives (Item h, M=4.73) and engaging in Clean, Drain, Dry behavior (item g, M=4.66).
Table 16. Attitudes Toward AIS
Item
Not at all
Somewhat
Significant
M
SD
1
2
3
4
5
%
a. How common are AIS (in primary boating state)?
.9
8.8
32.7
33.2
24.4
3.71
.96
b. How much of a problem are AIS (in primary boating state)?
1.1
8.0
32.2
33.1
25.7
3.74
.96
c. How much of a threat do AIS pose to the economy (of
primary boating state)?
1.3 7.0 24.6 31.0 36.1 3.94 1.00
d. How much of a threat do AIS pose to the health of
freshwater lakes and rivers (in primary boating state)?
.5 2.5 13.1 25.5 58.4 4.39 .84
e. How much of a threat do AIS pose to the health of
freshwater fish and wildlife (in primary boating state)?
.6 2.9 13.9 25.6 57.0 4.35 .87
f. How much of a threat do AIS pose to freshwater recreation
(in primary boating state)?
.8 4.4 16.6 26.9 51.3 4.24 .93
g. How important is removing plants/mud/organisms, draining
water from boat/compartments, drying completely?
.5 1.6 5 16.8 76.1 4.66 .70
h. How important do you think it is to prevent the spread of
aquatic invasive species?
.3 .9 4.2 14.5 80.1 4.73 .61
21
5.3 Exposure to Aquatic Invasive Species Messaging
Respondents were asked to indicate where they had received information about AIS in their state (Table
17). They were instructed to check all that apply. The most commonly reported source of information
was obtained at boat ramps or other signage (17.0%), followed by state agency websites (13.4%), and
then inspection station personnel (8.3%).
Table 17. Information Source
Information Source
n
%
Billboard
1022
5.9
Boat captain or fishing guides
354
2.0
Boat ramp or other signage
2957
17.0
Boating event (e.g., sailing regatta)
105
.6
Boating or fishing show
736
4.2
Conference, Meeting
120
0.7
Conservation organization
1110
6.0
Fishing Group
807
4.6
Fishing Tournament
194
1.1
Friends or Family
886
5.1
Inspection station personnel
1441
8.3
Internet search ads (e.g., Google)
433
2.5
Lake/homeowners association
348
2.0
Magazine
855
4.9
Newsletter
485
2.8
Newspaper
585
3.4
Other boaters
869
5.0
Radio
313
1.8
State agency website
2329
13.4
Other website
512
2.9
State social media
780
4.5
Other social media (e.g., fishing clubs)
454
2.6
TV
591
3.4
Other
238
1.4
Total
18524
100.0
22
5.4 Trust in Information Source
Respondents reported that the most trusted source of information (Table 18) came from state agency
websites (20.0%), followed by information at boat ramps or other signage (14.4%), and then inspection
station personnel (11.6%).
Table 18. Trust in Source of Information about AIS
Information Source
N
%
Billboard
313
2.3
Boat captain or fishing guides
374
2.7
Boat ramp or other signage
1970
14.4
Boating event (e.g., sailing regatta)
98
.7
Boating or fishing show
452
3.3
Conference, Meeting
167
1.2
Conservation organization
1236
9.0
Fishing Group
542
4.0
Fishing Tournament
134
1.0
Friends or Family
364
2.7
Inspection station personnel
1589
11.6
Internet search ads (e.g., Google)
226
1.7
Lake/homeowners association
205
1.5
Magazine
336
2.5
Newsletter
439
3.2
Newspaper
434
3.2
Other boaters
351
2.6
Radio
230
1.7
State agency website
2798
20.5
Other website
164
1.2
State social media
686
5.0
Other social media (e.g., fishing clubs)
199
1.5
TV
246
1.8
Other
110
.8
Total
13663
100.0
23
5.5 Perceived Effectiveness of Clean, Drain, Dry Messaging
Respondents were requested to indicate how effective they considered information on AIS for; a)
preventing the spread AIS, b) encouraging the adoption of Clean, Drain, Dry behaviors, and c) reaching
the population of boaters from across the state (Table 19).
For preventing the spread of AIS, boat ramp or other signage was considered to be most effective
(29.2%), followed by state agency websites (17.7%), and then inspection station personnel (16.1%).
With regard to the information source’s impact on the adoption of Clean, Drain, Dry behaviors, boat
ramp or other signage was again considered to be most effective (33.5%), followed by inspection station
personnel (18.9%), and then stage agency websites (11.5%).
Last, with regard to reaching the state’s population of boaters, boat ramp or other signage was
considered to be most effective (27.6%), followed by state agency websites (15.6%), and then television
(7.5%).
24
Table 19. Perceived Effectiveness of Information Source
Information Source
Preventing the spread
of AIS
Encouraging the adoption of
Clean, Drain, Dry Behaviors
Reaching the
Population of Boaters
n
%
n
%
n
%
Inspection station personnel
629
16.1
739
18.9
407
.4
Newspaper
34
.9
25
.6
40
1.0
TV
173
4.4
169
4.3
292
7.5
Radio
48
1.2
49
1.3
85
2.2
Newsletter
66
1.7
66
1.7
128
3.3
State social media
149
3.8
129
3.3
235
6.0
Other social media (e.g., fishing clubs)
77
2.0
98
2.5
154
3.9
Internet search ads (e.g., Google)
53
1.4
44
1.1
66
1.7
Magazine
16
.4
10
.3
26
.7
State agency website
691
17.7
447
11.5
608
15.6
Other website
10
.3
10
.3
15
.4
Other boaters
79
2.0
108
2.8
69
1.8
Billboards
149
3.8
135
3.5
240
6.2
Boat captains or fishing guides
34
.9
31
.8
27
.7
Boat ramp or other signage
1138
29.2
1305
33.5
1077
27.6
Fishing groups
103
2.6
116
3.0
88
2.3
Conservation organizations
211
5.4
159
4.1
114
2.9
Friends or family
33
.8
76
1.9
28
.7
Lake/homeowners association
41
1.1
36
.9
20
.5
Fishing Tournament
11
.3
12
.3
8
.2
Boating event (e.g., sailing regatta)
5
.1
5
.1
5
.1
Conference, meetings
7
.2
4
.1
2
.1
Boating or fishing show
57
1.5
48
1.2
59
1.5
Other
86
2.2
79
2.0
107
2.7
Total
3900
100.0
3900
100.0
3900
100.0
1=Not at all effective through 5=Extremely effective.
25
5.6 Message Experiment – Encouraging Clean, Drain, Dry
Respondents were presented with one of 20 messages and asked a series of questions about their
perception of whether or not the image would impact Clean, Drain, Dry behavior (See Appendix A3). The
messages were randomly assigned across the population of respondents. After being presented with the
message, respondents were then requested to respond to a series of questions concerning their; a)
perceptions of the message’s effectiveness for encouraging Clean, Drain, Dry behavior, b) raising their
concern over AIS, and c) the likelihood they would engage in Clean, Drain, Dry behavior on their next
boating trip.
We conducted an analysis of variance (ANOVA; When there was equality among the variances we used
Tukey’s post hoc comparisons. For unequal variances, we used Games-Howell comparisons test to
examine which message treatments were most likely to increase respondents Clean, Drain, Dry
behavior. While the F-value approached statistical significance (F=1.60 (df=19, 3,880), p=.049, η
2
=.008),
based on our post hoc message comparisons coupled with a very weak effect, we observed no
statistically significant variation.
Of the messages that received strongest agreement (M>3.40) in terms of their perceived effectiveness,
however, their message content addressed (Table 20):
a. Science-based metaphor (#15; M=3.43) - “PREVENT THE SPREAD OF AQUATIC INVASIVE SPECIES.
Aquatic invasive species are present in our state’s lakes and rivers and can severely impact these
ecosystems”;
b. Ecological gain (#9; M=3.41) – “PROTECT YOUR WATERS. CLEAN, DRAIN, DRY. Our aquatic
ecosystems will benefit tremendously”;
c. Protective/nurturing metaphor (#16; M=3.41) – “HELP PROTECT OUR WATERS. Aquatic invasive
species harm our lakes and rivers”;
d. Economic loss (#10; M=3.40) – “PROTECT YOUR WATERS. CLEAN, DRAIN, DRY. It will cost our
state (YOU) $ millions”;
e. I
njunctive norm (#13; M=3.40) – “PROTECT YOUR WATERS. the state’s boaters EXPECT you to
CLEAN, DRAIN, DRY your boat”;
f. Nativist metaphor (#17; M=3.40) – “NOT NATIVE, NOT WELCOME. Keep aquatic invasive species
out of our state’s lakes and rivers”; and
g. Militaristic metaphor (#18; M=3.40) – “STOP THE INVASION OF AQUATIC INVASIVE SPECIES.
Help fight the battle against aquatic invasive species”.
26
Table 20. Message Effect on Clean Drain Dry
1=Not at all effective through 5=Extremely effective
In your opinion, how effective would this message be at increasing boaters’
Clean, Drain, Dry behaviors?
n
M
SD
Message
1
195
3.28
.85
2
207
3.35
.75
3
198
3.32
.72
4
190
3.19
.79
5
199
3.26
.73
6
191
3.23
.78
7
195
3.32
.81
8
211
3.30
.80
9
205
3.41
.78
10
196
3.40
.81
11
139
3.29
.66
12
179
3.32
.87
13
181
3.40
.79
14
194
3.23
.78
15
199
3.43
.76
16
217
3.41
.81
17
194
3.40
.78
18
203
3.40
.79
19
200
3.37
.82
20
207
3.34
.71
Total
3900
3.33
3900
27
5.7 Message Experiment – Perceived Severity of Aquatic Invasive Species
Following the presentation of the treatment message, respondents were also asked to indicate the extent
to which they considered AIS to be a problem in their state. We conducted a chi-square test to examine
the distribution of responses across each of the treatment messages. The findings presented in Table 21
illustrate proportionate distribution across the response categories (i.e., extent of problem) for each of
the treatment messages. Response distributions were highly skewed; for all treatment messages, no less
than 80% of respondents acknowledged that AIS is “a problem” or “a major problem” within their state.
Table 21. Perceived Problem of AIS in State
Message
Treatment
Not sure
Not a
problem
A slight
problem
A problem
A major
problem
Total
0
1
2
3
4
n
%
n
%
n
%
n
%
n
%
n
%
1
8
4.1
3
1.5
25
12.8
80
41.0
79
40.5
195
100.0
2
5
2.4
2
1.0
22
11.3
94
45.4
84
40.6
207
100.0
3
7
3.5
2
1.0
18
9.2
101
51.0
70
35.4
198
100.0
4
6
3.2
3
1.6
12
6.2
90
47.4
79
41.6
190
100.0
5
6
3.0
1
.5
20
10.3
93
46.7
79
39.7
199
100.0
6
4
2.1
2
1.0
23
11.8
93
48.7
69
36.1
191
100.0
7
5
2.6
1
.5
14
7.2
95
48.7
80
41.0
195
100.0
8
6
2.8
0
.0
29
14.9
92
43.6
84
39.8
211
100.0
9
7
3.4
2
1.0
21
10.8
88
42.9
87
42.4
205
100.0
10
5
2.6
1
0.5
18
9.2
83
42.3
89
45.4
196
100.0
11
7
5.0
1
0.7
13
6.7
72
51.8
46
33.1
139
100.0
12
5
2.8
1
.6
16
8.2
94
52.5
63
35.2
179
100.0
13
5
2.8
2
1.1
19
9.7
84
46.4
71
39.2
181
100.0
14
2
1.0
2
1.0
23
11.8
100
51.5
67
34.5
194
100.0
15
7
3.5
0
.0
18
9.2
92
46.2
82
41.2
199
100.0
16
10
4.6
3
1.4
18
9.2
100
46.1
86
39.6
217
100.0
17
8
4.1
3
1.5
25
12.8
81
41.8
77
39.7
194
100.0
18
6
3.0
1
.5
19
9.7
91
44.8
86
42.4
203
100.0
19
5
2.5
0
.0
19
9.7
91
45.5
85
42.5
200
100.0
20
8
3.9
1
.5
16
8.2
109
52.7
73
35.3
207
100.0
Pearson Chi-Square (df)=55.85 (76), p=.960, Cramer’s V (ϕc)=.060
28
5.8 Message Experiment – Message Influence on Clean, Drain, Dry
Respondents were asked to indicate the likelihood that they would conduct the Clean, Drain, Dry
behaviors listed in Table 22. Based on the means reported in Table 24 and ANOVA reported in Table 23,
all messages were equally effective at encouraging Clean, Drain, Dry behavior. We observed no
statistically significant variation in the effectiveness of one message type over another. All messages
were equally effective at encouraging respondents to; a) clean mud, plants, and animals from their
boats and equipment, b) wash their boats and equipment with a pressure washer or hot water, c) drain
all water from their livewells, bilges, motors, and other receptacles, and d) dry their boat and equipment
for at least a week.
Across the behaviors, however, respondents appear to be more inclined to clean mud, plants and
animals from their boats and drain livewells, bilges, and motors rather than washing their boats and
equipment with pressure washers or hot water and drying their boats for a week before entering
another water body. The means for the former two behaviors hovered around 4.5 which approaches
“very likely” to engage whereas the means for the latter two behaviors hovered at or slightly below 4.0
indicating “likely”. Coupled with the findings presented in Tables 28, 32 and 33, respondents did indicate
that these latter two actions were more challenging.
29
Table 22. Message Influence on Clean, Drain, Dry Behavior
1=Not at all effective through 5=Extremely effective.
Based on the message you have just read, if you saw this message, how likely would you do the following
Clean, Drain, Dry behaviors the next time you go boating? (before launching in another waterbody)
Message
Clean mud, plants,
and animals from boat
and equipment
Wash boat and
equipment with pressure
washer or hot water
Drain all water from
livewells, bilges, motors,
and other receptacles
Dry boat and
equipment for
at least a week
1
M
4.30
3.70
4.35
3.95
SD
1.05
1.36
1.12
1.33
2
M
4.38
3.82
4.44
4.02
SD
.99
1.27
1.00
1.18
3
M
4.41
3.71
4.46
3.98
SD
.96
1.32
.95
1.23
4
M
4.37
3.64
4.44
4.01
SD
1.08
1.36
1.04
1.30
5
M
4.32
3.84
4.41
3.98
SD
1.05
1.25
1.10
1.24
6
M
4.27
3.70
4.38
3.92
SD
1.08
1.28
1.13
1.29
7
M
4.38
3.98
4.39
3.96
SD
1.02
1.22
1.01
1.24
8
M
4.32
3.81
4.33
3.86
SD
1.13
1.33
1.14
1.33
9
M
4.45
3.88
4.47
4.20
SD
1.02
1.33
1.04
1.14
10
M
4.37
3.96
4.49
4.15
SD
.94
1.25
.94
1.13
11
M
4.22
3.84
4.25
3.98
SD
1.22
1.27
1.26
1.23
12
M
4.39
3.56
4.47
4.06
SD
1.00
1.37
.96
1.21
13
M
4.34
3.72
4.48
4.05
SD
1.12
1.40
1.03
1.29
30
Table 23. Statistical Variation Among Message Treatments
Table 22 (continued). Message Influence on Clean, Drain, Dry
Message
Clean mud, plants,
and animals from boat
and equipment
Wash boat and
equipment with pressure
washer or hot water
Drain all water from
livewells, bilges, motors,
and other receptacles
Dry boat and
equipment
for at least a
week
14
M
4.36 3.69 4.43 3.94
SD
1.02
1.32
1.03
1.30
15
M
4.45
3.80
4.51
4.14
SD
.96
1.32
.95
1.18
16
M
4.36
3.62
4.45
3.96
SD
1.07
1.43
1.10
1.31
17
M
4.28
3.73
4.45
4.03
SD
1.11
1.37
1.04
1.30
18
M
4.49
3.79
4.51
4.06
SD
.87
1.31
.89
1.18
19
M
4.28
3.85
4.41
4.05
SD
1.20
1.30
1.14
1.33
20
M
4.40
3.75
4.48
4.09
SD
.98
1.32
.93
1.19
Total
M
4.36
3.77
4.43
4.02
SD
1.04
1.32
1.04
1.25
1=Not at all effective through 5=Extremely effective.
Based on the message you have just read, if you saw this message,
how likely would you do the following Clean, Drain, Dry behaviors the
next time you go boating?
df
F
p
a. Clean my boat, equipment, and trailers and remove mud, plants,
and animals before transporting my boat to another waterbody.
19 .79 .724
b. Wash my boat and trailer, e.g., with a pressure washer/spray
nozzle or hot water, before travelling to a new waterbody.
19 1.31 .165
c. Drain all water from my livewells, bilges, motors, and other
receptacles that have been in contact with water before leaving
that same waterbody.
19 .67 .850
d. Dry my boat and equipment for at least a week before launching
into other waters.
19 .90 .580
31
5.9 Frequency of Undertaking Clean, Drain, Dry
Respondents were requested to report on their Clean, Drain, Dry behavior over the past 12 months
(Table 24). They indicated engaging in cleaning mud, plants and the animals from their boat (M=4.23)
along with draining their livewells, bilges, and motors (M=4.45) more often than washing their boat and
equipment (M=3.17) and drying their boat for a week or more before entering another lake (M=4.07). In
particular, respondents were substantially less likely to report washing their boat with a pressure
washer or hot water compared to all other behaviors.
Table 24. Frequency of Undertaking Clean, Drain, Dry
Over the last 12 months, I have…
Never
Sometimes
About Half
the Time
Most of
the Time
Always
M
SD
1
2
3
4
5
%
a. Cleaned my boat, equipment, and
trailer and removed mud, plants,
and animals before transporting my
boat to another waterbody.
8.8 4.6 4.6 18.5 63.5 4.23 1.27
b. Washed my boat and trailer (e.g.,
with a pressure washer or hot
water) before traveling to a new
waterbody.
28.9 12.2 7.7 15.3 35.9 3.17 1.69
c. Drained all water from livewells,
bilges, motors, and other
receptacles that have been in
contact with water before leaving
that same waterbody.
7.1 3.1 2.1 13.6 74.2 4.45 1.15
d. Dried my boat for at least a week
before launching into other waters.
9.7 7.6 5.5 20.1 57.1 4.07 1.34
32
5.10 Perceived Effectiveness of Clean, Drain, Dry
Overall, respondents considered the array of Clean, Drain, Dry behaviors presented in Table 25 to be
effective in helping to minimize the spreads of AIS. The means on all items fell in the range of “quite
effective” to “very effective”.
Table 25. Effectiveness of Clean, Drain, Dry
How effective do you feel the following
behaviors are at stopping or reducing
the spread of aquatic invasive species
in [state]’s freshwaters?
Not at
all
effective
Slightly
effective
Neutral
Quite
effective
Very
effective
M
SD
1
2
3
4
5
%
a. Cleaning my boat, equipment, and
trailer and removing mud, plants,
and animals before transporting my
boat to another waterbody.
8.8 4.6 4.6 18.5 63.5 4.23 1.27
b. Washing my boat and trailer (e.g.,
with a pressure washer or hot
water) before traveling to a new
waterbody.
28.9 12.2 7.7 15.3 35.9 3.17 1.69
c. Draining all water from livewells,
bilges, motors, and other
receptacles that have been in
contact with river/lake waters
before leaving that same
waterbody.
7.1 3.1 2.1 13.6 74.2 4.45 1.15
d. Drying my boat for at least a week
before launching into other waters.
9.7 7.6 5.5 20.1 57.1 4.07 1.34
33
5.11 Perceived Difficulty of Undertaking Clean, Drain, Dry
Although respondents considered Clean, Drain, Dry actions to be effective in preventing the spread of
AIS, they indicated that some actions were more difficult to undertake than others (Table 26). Washing
boats with a pressure washer or hot water was considered most challenging with a third of respondents
(33.6%) reporting the task “difficult” to “very difficult”. Similarly, drying boats for at least a week was
also considered challenging for many boaters (26.8%). It is likely that many respondents do not have
access to a pressure washer or outdoor hot water and consider drying their boat for a week overly
burdensome. They may also not realize that drying their boat for an extended period of time is only
necessary when shifting to another waterbody.
Table 26. Perceived Difficulty of Clean, Drain, Dry
Please indicate how challenging you
consider each action
Extremely
difficult
Difficult
Not too
bad
Easy
Very
easy
M
SD
1
2
3
4
5
%
a. Clean my boat, equipment, and
trailers and remove any mud,
plants, and animals before
transporting my boat to another
waterbody.
1.8 6.6 29.9 28.6 33.0 3.84 1.02
b. Wash my boat and trailer (e.g., with
a pressure washer/spray nozzle or
hot water), before traveling to a
new waterbody.
10.9 22.7 29.3 18.5 18.6 3.11 1.26
c. Drain all water from my livewells,
bilges, motors, and other
receptacles that have been in
contact with public waters before
leaving that same waterbody.
2.2 5.3 16.3 25.0 51.1 4.17 1.03
d. Dry my boat and equipment for at
least 7-10 days before launching
into other waters.
10.4 16.4 21.2 19.8 32.3 3.47 1.36
34
5.12 Perception of Other Boaters’ Clean, Drain, Dry Behavior
The statements in Table 27 assess the extent to which respondents felt other boaters engaged in Clean,
Drain, Dry. Respondents did display some skepticism over other boaters’ adoption of Clean, Drain, Dry
behaviors. While the means in Table 27 hover around 3.0, many felt that other boaters “seldom”
engaged in Clean, Drain, Dry.
Table 27. Perception of Other Boaters’ Clean, Drain, Dry
How often do you think other
boaters…
Never
Seldom
Occasionally
Often
Always
1
2
3
4
5
%
M
SD
a. Clean their boat, equipment, and
trailers and remove mud, plants,
and animals before transporting
their boat to another waterbody.
5.2 28.7 35.6 26.8 3.7 2.95 0.95
b. Drain all water from their
livewells, bilges, motors, and
other receptacles that have been
in contact with public waters
before leaving that same
waterbody.
4.0 24.2 28.2 36.2 6.8 3.18 1.00
c. Dry their boat and equipment for
at least 7-10 days before
launching into other waters.
12.5 32.8 30.8 20.8 3.1 2.69 1.03
35
5.13 Expectation from Others to undertake Clean, Drian, Dry Behavior
The statements in Table 28 assess the extent to which respondents felt other boaters expected them to
Clean, Drain, Dry. Respondents did feel an expectation from other Boaters to Clean, Drain, Dry after
boating. Most respondents (>50%) expressed agreement with the statement, while many were
ambivalent (~30%) neither agreeing nor disagreeing.
Table 28. Perception of Other Boaters’ Expectation of Me to Engage in Clean, Drain, Dry
Other boaters expect me to…
Strongly
Disagree
Disagree
Neither
Agree
nor
Disagree
Agree
Strongly
Agree
M
SD
1
2
3
4
5
%
a. Clean my boat, equipment, and
trailers and remove any mud,
plants, and animals before
transporting my boat to another
waterbody.
2.3 6.3 31.6 40.8 19.1 3.68 0.93
b. Drain all water from my livewells,
bilges, motors, and other
receptacles that have been in
contact with public waters before
leaving that same waterbody.
2.3 6.0 29.5 39.4 22.8 3.74 0.95
c. Dry my boat and equipment for at
least 7-10 days before launching
into other waters.
6.6 12.3 35.7 30.9 14.4 3.34 1.08
36
5.14 Perceived Obligation to Engage in Clean, Drain, Dry Behavior
The statements in Table 29 capture the extent to which respondents feel a personal obligation to
engaging in Clean, Drain, Dry behaviors. These findings suggest that respondents do feel a personal
obligation to engage in Clean, Drain, Dry action. More than 80% of respondents expressed agreement
with all statements depicted in Table 29.
Table 29. Personal Obligations to Engage in Clean, Drain, Dry
Please indicate your level of agreement
with each statement.
Strongly
Disagree
Disagree
Neither
Agree
nor
Disagree
Agree
Strongly
Agree
M
SD
1
2
3
4
5
%
a. I feel a personal obligation to help
reduce the spread of aquatic
invasive species in [state].
.7 .6 6.5 37.1 55.2 4.45 .71
b. I feel morally obliged to help stop
the spread of aquatic invasive
species in [state], regardless of
what others do.
.8 1.3 7.5 37.1 53.2 4.40 .76
c. I feel guilty when I do not Clean,
Drain, and Dry my boat.
3.5 6.4 25.9 30.9 33.3 3.84 1.07
d. People like me should do whatever
they can to stop the spread of
aquatic invasive species in [state].
.7 .6 5.7 37.7 55.3 4.46 .70
37
5.15 Constraints to Undertaking Clean, Drain, Dry Behavior
Respondents asked if there was anything that kept them from engaging in Clean, Drain, Dry behavior.
Twenty-five percent indicated “yes” (Table 30). Of those, they expressed strongest agreement on two
items (Table 31); a) “There are no cleaning stations to do Clean, Drain, Dry” (M=3.93, item g), and b)
“Public access points or boat ramps are too crowded” (M=3.27, item a).
Table 30. Constraints to Engaging in Clean, Drain, Dry
Table 31. Individual Behaviors - Constraints to Engaging in Clean, Drain, Dry
n
%
No
2916
74.8
Yes
984
25.2
If yes, please indicate the extent to
which any of the following keeps you
from being able to do Clean, Drain, Dry.
Strongly
Disagree
Disagree
Neither
Agree
nor
Disagree
Agree
Strongly
Agree
M
SD
1
2
3
4
5
%
a. Public access points or boat ramps
are too crowded.
8.2 18.3 26.7 31.7 15.0 3.27 1.17
b. I do not understand what I need to
do.
39.5 40.1 13.4 5.2 1.7 1.89 .94
c. I don’t think that stopping the spread
of aquatic invasive species is
important.
59.5 32.6 4.9 2.0 1.0 1.53 .77
d. I am not physically able to do Clean,
Drain, Dry.
38.8 36.2 13.3 8.5 3.2 2.01 1.07
e. I do not think Clean, Drain, Dry will
stop the spread of aquatic invasive
species.
34.7 39.3 14.4 8.2 3.4 2.06 1.06
f. Aquatic invasive species don’t affect
me.
48.3 35.9 10.5 3.7 1.7 1.75 .91
g. There are no cleaning stations to do
Clean, Drain, Dry.
4.8 6.1 13.8 41.8 33.5 3.93 1.07
h. After boating, I do not have the time.
18.5
33.5
26.3
18.6
3.0
2.54
1.08
i. I do not know what to look for with
regards to aquatic invasive species.
23.2 36.3 2.4 15.9 4.3 2.42 1.13
j. After boating, I am too tired to Clean,
Drain, Dry.
21.7 36.3 24.3 15.8 1.9 2.40 1.05
k. Other boaters aren’t Cleaning,
Draining, and Drying their watercraft.
15.8 16.7 34.6 25.1 7.9 2.93 1.17
l. I do not think that anything I do will
prevent the spread of aquatic
invasive species.
35.6 37.9 15.0 8.5 2.9 2.05 1.05
38
5.16 Trust in State to Manage Aquatic Invasive Species
In the context of the management of AIS within respondents’ state, there was relatively strong
agreement with statements indicating that the state provides trustworthy and timely information about
AIS issues, best practices for AIS prevention, and has the capacity to prevent and manage AIS (Table 32).
Table 32. Trust in State to Manage AIS
With respect to AIS management, I
trust the state/province of [state] to…
Strongly
Disagree
Disagree
Neither
Agree
nor
Disagree
Agree
Strongly
Agree
M
SD
1
2
3
4
5
%
a. … provide the best available
information on aquatic invasive
species issues.
1.6 3.9 10.8 46.0 37.7 4.14 .87
b. … provide me with enough
information to know what actions I
should take regarding aquatic
invasive species prevention.
1.6 3.6 10.9 47.9 36.1 4.13 .86
c. … to take action to prevent and
manage invasive species.
2.3 5.4 12.7 44.9 34.7 4.04 .95
d. … provide timely information
regarding aquatic invasive species.
1.9 4.8 11.6 46.6 35.1 4.08 .91
39
5.17 Comparisons of Select Variable by Boater Characteristics
In follow-up analyses, we examined variation on a number of select variables using several boater
characteristics (see Appendix B). Discussion below is restricted to states where respondents had
completed 50 or more questionnaires. Key findings:
1. Familiarity with AIS. Respondents were presented with five statements examining their
familiarity with AIS in their primary boating state. The statements assessed their familiarity with
AIS prior to taking the survey, Clean, Drain, Dry behavior, AIS detected in their state, locations of
detection, and problems cause by AIS. The pattern of findings were generally consistent on all
five statements. The following respondents reported being most aware;
a. Residents of Nevada, and Utah.
b. Houseboat owners.
c. Tournament anglers.
d. Avid boaters.
2. Knowledge of AIS. Respondents were presented with eight statements examining their
knowledge of AIS within their primary boating state as it pertains to their prevalence, impact on
the economy, ecology, and recreation in addition to the importance of preventing the spread of
AIS through Clean, Drain, Dry action. The pattern of findings varied along several dimensions;
a. In terms of prevalence, Kansas respondents considered AIS to be most prevalent and
Alaskan respondents least prevalent.
b. In terms of concern over AIS, while most respondents expressed concern over the
presence of AIS, respondents from Alaska, Idaho, and Oregon were least concerned.
Among other groups, hunters were also expressed less concern whereas respondents
aged between 18-25 years were more concerned.
c. With regard to AIS’ impact on state’s economies, there was broad concern across all
segments of the boating population.
d. For concern over the health of the state’s lakes and rivers and freshwater fish and
wildlife, respondents were unanimous in both the strength of their conviction and level
of concern over the threat posed by AIS. All boating segments considered AIS to be a
significant threat to the health of the ecosystem.
e. All boating segments considered Clean, Drain, Dry important in addition to efforts to
prevent the spread of AIS.
3. Information Sources for AIS. Respondents were presented with 24 information sources and
requested to select all sources from which they have heard or received information about AIS.
Patterns across respondent segments included:
a. Boat ramps and other signage, and state agency website were consistently the most
popular information sources.
b. Inspection site personnel and state social media pages were more frequently reported
as information sources in states that emphasized AIS education programs and were less
frequently reported as information sources in states with less AIS-focused programs.
c. Tournament anglers were more likely to report social connections as information
sources about AIS.
d. Female respondents were more likely to report friends and family as information
sources about AIS, whereas male respondents were more likely to report all other
sources.
40
4. Trusted AIS Information Sources. Respondents were presented with 24 information sources and
requested to identify all information sources that they trusted most to provide information
about AIS. Patterns in the findings included:
a. State agency websites were selected as the most trusted information sources across all
respondent segments.
b. Boat ramp signage, inspection station personnel, and conservation organizations were
also consistently selected as trusted information sources across watercraft and activity
types, ages, and genders.
c. Beyond state agency websites, state agency social media accounts were more likely to
be a trusted information source about AIS for those ages 26-45. While younger (18-25)
respondents were more likely to trust conservation organizations, older respondents
(65+) were more likely to trust inspection station personnel.
5. Effective AIS Information Sources. Respondents were presented with 24 information sources and
requested to report which source they perceived as most effective at; (a) preventing the spread
of AIS, (b) encouraging people to adopt Clean, Drain, Dry behaviors, and (c) reaching the
population of boaters across the state/province. The most prominent patterns of findings were:
a. Boat ramps and other signage, inspection station personnel, and state agency websites
were consistently found to be most effective at preventing the spread of AIS,
encouraging people to adopt Clean, Drain, Dry behaviors, and reaching the population
of boaters.
b. Houseboat owners were consistently more likely to report inspection station personnel
as more effective across all segments whereas john boat and bass boat owners were
more likely to view boat ramps and other signage as most effective.
c. Older respondents were more likely to view state agency websites as most effective at
preventing the spread of AIS and encouraging use of Clean, Drain, Dry behaviors relative
to younger respondents. Younger respondents were more likely to report conservation
organizations and inspection station personnel as being most effective at preventing the
spread of AIS and encouraging use of Clean, Drain, Dry behaviors.
6. The Extent of the AIS Problem. Respondents were presented with a question asking about the
extent they feel aquatic invasive species are a problem in their primary boating state. Most
notable findings were:
a. Across all segments, respondents reported that they feel aquatic invasive species are a
problem in their primary boating state.
b. Respondents boating in Montana and respondents residing in Utah reported feeling
most concerned that aquatic invasive species are a problem in their primary boating
state.
c. Respondents boating and residing in Alaska reported feeling the least concerned that
aquatic invasive species are a problem in their primary boating state.
d. Among watercraft types, houseboat owners reported feeling the most concerned that
aquatic invasive species are a problem.
e. Among activity types, wake sports participants were most likely to feel that aquatic
invasive species are a problem.
f. Among age groups, respondents 56 years and older tended to consider AIS most
problematic.
7. Likelihood of Engaging in Clean, Drain, Dry. Respondents were presented with four statements
examining how likely they would engage in different actions related to Clean, Drain, Dry
practices to prevent the spread of AIS; a) cleaning their boat and equipment before transporting
their boat to another waterbody, b) washing their boat and trailer (e.g., with a pressure washer
41
or hot water) before travelling to a new waterbody, c) draining all water from receptacles that
have been in contact with public waters before leaving that same waterbody, and d)drying their
boat and equipment for at least a week before launching into other waters. Most notable
patterns in the findings were:
a. Likelihood of engagement in all actions pertaining to Clean, Drain, Dry behaviors was
high.
b. In regard to cleaning behaviors, Arizona respondents were most likely to clean their
boat and equipment before transporting to other waterbodies and Alaskan respondents
were least likely.
c. For washing behaviors, Wyoming respondents were most likely to wash their boat and
equipment before travelling to a new waterbody and Alaskan respondents were least
likely.
d. For draining behaviors, Kansas respondents were most likely to drain water from
receptacles that came in contact with public waters before leaving that waterbody and
Alaskan and Washington respondents were least likely.
e. In terms of drying behaviors, Arizona respondents were most likely to dry their boats
and equipment for at least a week before launching into other waters and Alaskan
respondents were least likely.
f. Across all segments, respondents reported the highest likelihood of engaging in cleaning
and drying behaviors and least likely to engage washing with hot water or a pressure
washer.
8. Frequency of Clean, Drain, Dry. Respondents were presented with four items asking about the
frequency of their engagement in Clean, Drain, Dry behavior; a) cleaning their boat and
equipment before transporting their boat to another waterbody, b) washing their boat and
trailer (e.g., with a pressure washer or hot water) before travelling to a new waterbody, c)
draining all water from receptacles that have been in contact with public waters before leaving
that same waterbody, and d) drying their boat and equipment for at least a week before
launching into other waters. Most notable patterns in the findings were:
a. Across all segments, respondents reported engaging in Clean, Drain, Dry behavior.
However, reported frequency of respondent’s engagement in washing their boat and
trailer before travelling to a new waterbody was lower than frequency of engagement in
other Clean, Drain, Dry behaviors.
b. Consistent on all Clean, Drain, Dry behaviors, both respondents boating in Alaska and
residing in Alaska reported least frequent engagement.
c. Regarding cleaning behaviors, respondents boating and residing in Montana most
frequently engaged in cleaning their boat and equipment before transporting to other
waterbodies.
d. For washing behaviors, respondents boating in Arizona and respondents residing in
Montana most frequently engaged in washing their boat and equipment before
travelling to a new waterbody and Alaskan respondents were least frequent.
e. For draining behaviors, respondents boating and residing in Colorado most frequently
engaged in draining all water from receptacles that came in contact with public waters
before leaving that waterbody and Alaskan and Washington respondents were least
likely.
42
f. In terms of drying behaviors, respondents boating and residing in Utah most frequently
engaged in drying their boats and equipment for at least a week before launching into
other waters.
g. Among watercraft types, houseboat owners reported the most frequent engagement in
Clean, Drain, Dry behaviors.
h. While wake sports participants reported most frequent engagement in washing and
drying behaviors, tournament fishing participants reported most frequent engagement
in cleaning and draining behaviors.
1. Perceived Effectiveness of Clean, Drain, Dry. Respondents were presented with four statements
examining their perceptions of effectiveness of certain Clean, Drain, Dry behaviors. Specifically,
respondents were asked judge the effectiveness of the following behaviors: cleaning their boat
and equipment before transporting it to another waterbody, washing their boat and equipment
(e.g., with a pressure water or hot water) before traveling to a new waterbody, draining all
water from receptacles that have been in contact with public waters before leaving that same
waterbody, and drying their boat for at least a week before launching into other waters.
Patterns in the findings were;
a. Across respondent segments, cleaning and draining practices, specifically, were viewed
as most effective at preventing the spread of AIS. Washing actions were considered
least effective.
b. Regarding cleaning behaviors, Montana respondents viewed cleaning boats and
equipment before transporting to another water to be most effective as preventing the
spread of AIS and Alaskan respondents viewed cleaning practices as least effective.
c. For washing behaviors, Arizona respondents viewed washing boats and equipment
before transporting to a new waterbody as most effective in preventing the spread of
AIS and Californian and Alaskan residents viewed washing practices as least effective.
d. In terms of draining behaviors, Wyoming respondents viewed draining all water from
receptacles that had been in contact with public waters before leaving that same
waterbody as most effective in preventing the spread of AIS and Alaskan respondents
viewed draining practices as least effective.
e. For drying behaviors, Washington respondents viewed drying boats and equipment for
at least a week before launching into other waters as most effective at preventing the
spread of AIS and Alaskan respondents viewed drying practices as least effective.
10. Perceived Difficulty of Clean, Drain, Dry. Respondents were presented with four different actions
related to Clean, Drain, Dry best practices and were asked to rate the level of difficulty for each
action. The actions included cleaning boats and equipment before transporting to another
waterbody, washing boats and trailers before traveling to another waterbody, draining all water
from receptacles that came in contact with public waters before leaving that same waterbody,
and drying boats and equipment for at least a week before launching into other waters.
Prominent patterns in the findings included:
a. Across all segments, respondents found clean and draining best practices to be easy to
very easy, while washing and drying behaviors were perceived to be more difficult.
b. Boaters in Alaska, as well as residents of Alaska, consistently perceived the most
difficulty in engaging in Clean, Drain, Dry best practices across all behaviors.
c. Across states, washing boats and equipment with a pressure washer or hot water before
traveling to another waterbody was perceived to be the most difficult Clean, Drain, Dry
action.
43
d. For all watercraft types, respondents perceived the Clean, Drain, Dry behaviors to be not
too difficult to easy.
e. Overall, Clean, Drain, Dry behaviors were perceived to generally be not too difficult or
easier across all respondent characteristics.
11. Beliefs About Other Boaters’ Clean, Drain, Dry Behavior. Respondents were presented with a
series of questions asking about their beliefs about the frequency of other boaters’ engagement
in Clean, Drain, Dry behaviors related to; a) cleaning their boat and equipment before
transporting their boat to another waterbody, b) draining all water from receptacles that have
been in contact with public waters before leaving that same waterbody, and c) drying their boat
and equipment for at least a week before launching into other waters. Most notable patterns in
the findings were:
a. Consistent across all Clean, Drain, Dry behaviors, respondents boating and residing in
Alaska believed other boaters were least often engaging in Clean, Drain, Dry behaviors.
b. Regarding cleaning behaviors, respondents boating and residing in Colorado believed
other boaters were most often engaging in cleaning their boat and equipment before
transporting to other waterbodies.
c. In terms of draining behaviors, respondents boating in Arizona and respondents residing
in Colorado and Nevada believed other boaters were most often engaging in draining all
water from receptacles that came in contact with public waters before leaving that
waterbody.
d. Similar to cleaning and draining behaviors, respondents boating in Arizona and
respondents residing in Utah believed other boaters were most often engaging in drying
their boats and equipment for at least a week before launching into other waters.
e. Among all watercraft types, houseboat owners believed other boaters were most often
engaging in Clean, Drain, Dry behaviors.
f.
Among all activity types, wake sports participants believed other boaters were most
often engaging in Clean, Drain, Dry behaviors.
g. Consistent on all Clean, Drain, Dry behaviors, as boating frequency increased in spring,
summer, and fall, beliefs about the frequency of others engaging in Clean, Drain, Dry
behaviors decreased.
h. White, Spanish, Hispanic, and Latino respondents indicated that they believed other
boaters engage in Clean, Drain, Dry behaviors most often.
12. Beliefs About Other Boaters’ Expectations Regarding Clean, Drain, Dry. Respondents were
presented with a series of statements relating to their beliefs about other boaters’ expectations
of their use of Clean, Drain, Dry. Respondents were asked to indicate their level of agreement to
three statements concerning; a) cleaning their boat, equipment, and trailers and remove any
mud, plants, and animals before transporting their boat to another waterbody, b) draining all
water from their receptacles that have been in contact with public waters before leaving that
same waterbody, and c) drying their boat and equipment for at least 7-10 days before launching
into other waters. Most notable patterns in the findings were:
a. Across all segments, respondents agreed that other boaters expected them to engage
in Clean, Drain, and Dry.
b. Consistent on all Clean, Drain, Dry behaviors, respondents boating in Alaska and residing
in Alaska reported the least agreement that other boaters expect them to engage in
Clean, Drain, Dry.
c. Regarding cleaning behaviors, respondents boating and residing in Utah indicated the
most agreement that other boaters expect them to clean their boat, equipment, and
44
trailers and remove any mud, plants, and animals before transporting their boat to
another waterbody.
d. For draining behaviors, respondents boating and residing in Colorado and Utah reported
the highest level of agreement about other boaters’ expectations regarding draining
water from all receptacles before leaving a waterbody.
e. In terms of drying behaviors, respondents boating and residing in Utah reported the
highest level of agreement about other boaters’ expectations regarding drying their
boat and equipment for at least 7-10 days before launching into other waters.
f. Among watercraft types, houseboat owners reported the highest level of agreement
about other boaters’ expectations regarding Clean, Drain, Dry.
g. Among activity types, wake sports participants reported the highest level of agreement.
h. Among racial groups, White and Spanish/Hispanic/Latino reported the highest level of
agreement that other boaters expect the respondent to engage in Clean, Drain, Dry.
13. Beliefs About Clean, Drain, Dry and AIS. Respondents were presented with four statements
examining their beliefs surrounding the responsibility of engaging in Clean, Drain, Dry, and
reducing the spread of AIS. Specifically, respondents were presented with each of the following
statements; a) feeling a personal obligation to help reduce the spread of aquatic invasive
species, b) feeling morally obliged to help stop the spread of AIS (regardless of what others do),
c) feeling guilty when they do not engage in Clean, Drain, Dry, and d) that people like them
should engage in Clean, Drain, Dry. Most notable patterns in the findings were:
a. The level of agreement to these statements was generally high apart from feeling guilty
when not engaging in Clean, Drain, Dry. Agreement to this statement was still
moderately high, but markedly lower than the other three statements.
b. Colorado boaters felt the strongest personal obligation to reduce the spread of AIS.
c. Montana boaters (with Colorado close behind) felt the most obliged to stop the spread
of AIS in their primary boating state.
d. Wyoming boaters felt the guiltiest when they did not engage in Clean, Drain, Dry.
e. Montana boaters felt that people like them should do whatever they can to stop the
spread of AIS in their primary boating state.
f. Houseboat owners were in the most agreement with all four statements.
g. People participating in wake sports were in most agreement with all four statements.
14. Twenty five percent of respondents (n=984) indicated that some form of constraint prevented
them from undertaking Clean, Drain, Dry. These respondents were requested to indicate their
level of agreement with 12 statements that could potentially obstruct their ability to Clean,
Drain, Dry. Below, we report highlights from boating groups with at least 10 or more responses:
a. Access points too crowded.
• Boaters both residing in Washington and boating in Washington.
• Houseboat owners and ski/wakeboard boaters.
• Wake sports participants.
b. Not understanding what needs to be done.
• For the most part, all respondents reported understanding what needs to be done
in terms of Clean, Drain, Dry.
c. Perception of the importance of stopping the spread of AIS.
• For the most part, all respondents understood the importance of stopping the
spread of AIS.
d. Physical ability to Clean, Drain, Dry.
• All respondents expressed the capacity to undertake Clean, Drain, Dry.
45
e. Perception that Clean, Drain, Dry will not help prevent the spread of AIS.
• All respondents shared the belief that Clean, Drain, Dry will help prevent the spread
of AIS.
f. Personal impact if AIS.
• While all boaters were concerned about the personal impact of AIS, those
expressing slightly less concern were respondents from Alaska, houseboat and
ski/wakeboarders, and wake sports participants.
g. Absence of cleaning stations.
• Most respondents agreed that the absence of cleaning stations was constraining
their ability to Clean, Drain, Dry. Respondents from Alaska were most inclined to
indicate this constraint.
h. Too little time.
• While there was little variation across boating groups indicating that they had too
little time to Clean, Drain, Dry, there was moderate level of agreement with the
statement.
i. Not knowing what to look for.
• Generally, most boaters reported being aware of what to look for with regard to
AIS.
j. Too tired.
• Each of the boating groups reported that fatigue was a not a substantial constraint.
k. Other boaters’ behavior.
• While there was little variation among boating groups over their concern for other
boaters not undertaking Clean, Drain, Dry, there was a universal degree of
skepticism over others’ compliance.
l. Capacity to prevent the spread AIS.
• All boating groups were confident in their capacity to prevent the spread of AIS.
15. Trust in State/Province Actions. Respondents were presented with a series of statements
relating to their trust in different actions of the state/province. Respondents were asked to
indicate their level of agree to four statements about state/province of state’s actions.
Specifically, these included; a) trusting the state/province to provide the best available
information on AIS issues, b) provide people with enough information to know what actions
they should take to regarding AIS prevention, c) to take action and manage invasive species,
and) provide timely information regarding AIS. Comparisons were made across these statements
in several domains. Most notable patterns in the findings were:
1. Respondents generally agreed they trust the state to provide good and accurate
information regarding AIS. However, trust in the state to take action to prevent and
manage invasive species was the least.
2. Wyoming and Arizona boaters trusted their states most. Whereas California, Alaska,
and Oregon trusted them the least.
3. Wake sport participants were consistently had the highest level of trust in the state.
4. While generally expressing trust in state agencies (means of four on the five point
scale), tournament anglers, hunters, cabin cruiser/center console boat owners, and
younger respondents scored consistently scored lower than other groups.
5.18 Message Treatment Follow-up Analyses
46
To further explore variation among select groups with regard to the effectiveness of our message
treatment, we conducted follow-up analyses on message treatments that respondents considered to be
most effective at encouraging Clean, Drian, Dry (see Appendix C). Following the presentation of the
message/image to respondents, respondents were asked, “In your opinion, how effective would this
message be at increasing boaters’ Clean, Drain, Dry behaviors?” Responses ranged along a 5-point scale
where 1=”not at all effective” through 5=”extremely effective”. Messages the respondents considered
most effective (with means > 3.4) consisted of all four metaphor-based messages, economic loss and
ecological gain, and the injunctive norm message. For these messages, we examined variation by
watercraft type, activity type, household income, and gender.
We observed statistically significant variation science- and militaristic-based metaphors only. For the
science metaphor, houseboat owners and men considered the message most effective for encouraging
Clean, Drain, Dry. For the militaristic metaphor, kayak/canoe//paddleboard owners considered the
message least effective. We observed no variation among groups for the remaining treatment
messages. All groups considered the message equally effective.
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6.0 DISCUSSION & RECOMMENDATIONS
In this section of the report, we document findings stemming from analyses and offer selected
recommendations. Key findings suggest:
1. Likely an artifact of our sample’s homogeneity, socio-demographic variables related to
education, race, and income did not consistently reveal variation or associations with factors
related to familiarity with AIS, adoption of Clean, Drain, Dry, and other associated variables. The
characteristics of the sample is, however, broadly reflective of the boating public. Efforts to
target messaging campaigns at select groups based on these attributes would not likely produce
a significant shift in boaters’ awareness, knowledge, and behavior.
a. Age, however, was more strongly associated with awareness, knowledge and Clean,
Drain, Dry behavior. Likely an artifact of exposure to AIS messaging through their years
of boating experience, older boaters expressed greater awareness, knowledge, and
willingness to adopt Clean, Drain, Dry. Messaging toward a younger cohort ought to
occur early in their boating careers. Beyond the most popular sources (i.e., boat
ramps, state agency websites, and inspection stations), these messages could be
delivered with boat registration and fishing license renewals.
2. Respondents were familiar with AIS before taking the survey along with the need to Clean,
Drain, Dry. They were, however, less familiar with both the species of AIS that had been
detected in the state where they primarily boat in addition to the locations (waterbodies) in the
state where AIS had been detected.
a. Familiarity with AIS (prior to taking survey) was linked to the extent to which
respondents interacted with the resource (e.g., houseboat owners, tournament anglers,
avid boaters). Those least familiar with AIS reported (e.g., pontoon and sailboat owners,
paddlers, hunters) less concern over AIS and a lower likelihood of implementing Clean,
Drain, Dry. Those most actively interacting with the resource will likely encounter AIS
messaging through the most popular sources of information (boat ramp kiosks, state
agency websites, inspection stations), whereas accessing infrequent boaters will be an
ongoing challenge. Point of sale for non-motorized watercraft (e.g., decals placed on
the watercraft) and hunting licenses provides one opportunity for agency contact.
3. Respondents were aware of the importance of Clean, Drain, Dry for preventing the spread of
AIS. They also indicated being aware of the threat posed by AIS to the health of their state’s; a)
freshwater lakes and rivers, b) freshwater fish and wildlife, and c) freshwater recreation.
a. States with invasive mussel infestations and active watercraft inspection and
decontamination programs (e.g., Utah, Nevada) appear to have had most success with
raising public awareness. Beyond kiosks at boat ramps and their state agency websites,
respondents from these states were also more likely to report receiving information
from inspection stations. Inspection stations provide an opportunity for agencies to
directly communicate with boaters, dispel myths and misinformation, and provide up
to date information about the health of specific lakes and necessary precautions.
b. Among use groups, houseboat owners and wakesports users expressed greatest
awareness for the need for Clean, Drain, Dry whereas non-motorized users and hunters
expressed the greatest ambivalence. For non-motorized users, information about AIS
and Clean, Drain, Dry could be placed on the product at the point of sale. For hunters,
48
principally waterfowl, information about AIS and Clean, Drain, Dry could also be
shared with the purchase of duck stamps and hunting licenses.
4. In terms of AIS information to which respondents had been previously exposed:
a. Most common sources were boat ramp kiosks, followed by the state’s agency website,
and then inspection station personnel. For these information sources, respondents
indicated that their state’s agency websites were most trusted, followed by boat ramp
kiosks, and then state inspection personnel. AIS information should be easily accessible
on agency websites. Given their broad coverage and, importantly, boaters’ trust in the
state to provide up to date information about AIS, access to this information on
agency websites should feature prominently.
b. Referencing the same information sources, respondents were asked to indicate how
effective the information was for preventing the spread of AIS, encouraging Clean,
Drain, Dry, and reaching the population of boaters. Similar to respondents’ exposure
and trust, boat ramp signage, state agency websites, and state inspection personnel
were considered most effective for preventing the spread of AIS, encouraging Clean,
Drain, Dry, and reaching the population of boaters. Residents of states utilizing
inspection stations (e.g., California, Utah, Nevada) expressed greater trust in the
information provided by inspection station personnel, considered the information
more effective at preventing the spread of AIS, and more effective at encouraging
Clean, Drain, Dry. While the coverage of the information provided by inspection
station personnel is geographically limited, it is clearly a useful tool and one that
warrants consideration/adoption.
c. Beyond state agency websites, state agency social media accounts were more likely to
be a trusted information source about AIS for those aged 26-45. While younger (18-25)
respondents were more likely to trust conservation organizations. Conservation
organizations (e.g., CCA) provide an opportunity to develop strategic partners that can
help amplify agency efforts through social media, their agency websites, and through
members’ social networks. Regular active engagement with these partners would also
assist in providing up to date information.
5. With regard to our messaging experiment, following the presentation of the image/message to
respondents, they were requested to:
a. Indicate the extent to which the message would encourage others to engage in Clean,
Drain, Dry – Respondents indicated that the messages would have modest impact on
encouraging others’ Clean, Drain, Dry behavior. While all messages were equally
effective, there was some ambivalence over the messages’ potential to shift others’
behavior.
b. Indicate the extent to which they considered AIS to be a problem in their state –
Message treatments had equal influence on the extent to which respondents
considered AIS to be a problem. For all messages, over 80% of respondents considered
AIS “a problem”.
c. Indicate the extent to which they would engage in Clean, Drain, Dry – All message
treatments were equally effective at encouraging respondents to engage in Clean,
Drain, Dry on their next boating trip. Actions considered most effective related to
cleaning and draining boats. The message’s influence on washing and drying actions
were considered to be less effective.
49
While we observed no statistically significant variation among message treatments – all
moderately effective at encouraging Clean, Drain, Dry – seven messages were somewhat
superior. For future messaging efforts, agencies should consider elements of each message or
in combination when designing persuasive appeals.
As previously noted, a number of the message treatments were drawn from past work
conducted in the context of the human dimensions of aquatic invasive species and conservation
behavior. For the identify frames, Fielding and associates’ work on social identity and its
association conservation-related behaviors (Fielding & Hornsey, 2016; Schultz & Fielding, 2014;
Unsworth & Fielding, 2014) revealed that messages that make salient an individual’s ingroup
membership (e.g., boater, hunter, paddler, angler) have greater persuasive power than
messages to which the individual has no affiliation. While statistically significant variation was
not observed across the different identities, respondents receiving the message identifying
“anglers” considered the message to be most effective at encouraging Clean, Drain, Dry
behaviors among the four identify frames. Overall, respondents considered the identity frames
least effective compared to other frames at encouraging Clean, Drain, Dry.
Similarly, the environment and economic gain/loss scenarios were drawn from Degolia, et al.’s
(2019) work within the context of wild pig management. Their work revealed that messages
framed in terms of environmental outcomes, as opposed to economic, elicited more support for
AIS management among a sample of California residents. Also, messages referencing economic
and environmental loss drove stronger support for AIS management compared to messages
referencing gain. While we did not observe statistically significant variation across these
message frames, respondents receiving the economic loss and ecological gain messages were
most inclined to indicate that the message would encourage Clean, Drain, Dry. Research in
behavioral economics (Kahneman & Tversky, 1977) has consistently shown that consumers are
less accepting losing economic standing (loss aversion) than of gaining. Alternately, the prospect
of an ecological gain reflected in the ecological treatment was perceived to be influential in
encouraging Clean, Drain, Dry. Framing the impact of AIS on aquatic ecosystems and the
state’s economic health is compelling.
Economic Loss
Ecological Gain
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The normative message frames were
drawn from the work of Wallen and Kyle
(2018) who explored the effective of
normative message framing and its impact
on Clean, Drain, Dry among Texas boaters.
Like Wallen and Kyle, we observed no
statistically significant variation among the
different types of normative frames.
However, respondents receiving the
injunctive normative message considered
the message to be most effective at
encouraging Clean, Drain, Dry. Unlike the
descriptive norm, the injunctive norm
message attempts to instill a personal
obligation that rests on the perception of
others’ expectations.
Injunctive Norm
Last, metaphor themed frames were drawn from Shaw et al.’s (2021) and their work relating to
messaging to prevent the spread of zebra mussels. These metaphors touched upon themes
related to; a) science with objective, fact-based information, b) the protection of nature with a
nurturing statement related to protecting the environment, c) non-nativist with reference to
alien species, and d) militaristic with reference to battles against invasives. While we did not
observe statistically significant variation, all metaphor themes performed comparatively well
compared to other message treatments. The science metaphor, like Shaw et al., was the
strongest performer in terms of respondents’ reported effectiveness for encouraging Clean,
Drain, Dry.
Militaristic Metaphor
Protective Metaphor
51
Nativist Metaphor
Science Metaphor
6. For the follow-up analyses where we examined variation across groups (activity type, watercraft
type, gender, and household income) for the best performing message treatments, we saw little
variation across groups. The science-based metaphor was considered most effective for
houseboat owners and men whereas the militaristic metaphor was considered least effective by
kayak/canoe/paddleboard owners. Broadly, subgroups consider these messages to be equally
effective.
7. In terms of the extent to which respondents considered AIS a problem in their state, concern
varied in ways similar to their perceptions of the effectiveness of information about AIS and
their perceived effectiveness and willingness to implement Clean, Drain, Dry. Alaskans were less
concerned whereas houseboat owners and wakesports participants were most concerned. For
states where respondents expressed least concern, it is likely an artifact of the state’s
willingness to promote information about AIS and/or the extent to which AIS is a problem
within the state. For non-motorized users (e.g., paddle boards, kayaks) the ambivalence might
relate to the perception that these types of watercraft are unlikely to be problematic owing to
the (mis)perception that they don’t hold water in volumes that could be problematic (e.g.,
absence of bilges or bait tanks). Placing stickers with Clean, Drain, Dry messaging on the
watercraft at sale may be one way to advance messaging. Similar groups’ familiarity, boaters
with extensive interaction with the resource (e.g., houseboat owners, wakesports participants)
considered AIS most problematic. Older respondents (> 55 years) also considered AIS more
problematic than younger respondents. For those respondents most extensively interacting
with the resource they are witnessing, firsthand, the impact of AIS. For younger respondents,
however, the problem of a shifting baseline (Soga & Gaston, 2018) that allows for greater
tolerance of AIS might underlie greater acceptance due to a lack prior experience of past
conditions. For younger respondents, the normative condition may well be the present
condition. Follow-up analyses (Appendix C) examining variation in respondents’ perceived
effectiveness of our message treatments for encouraging Clean, Drain, Dry also revealed
younger respondents were more ambivalent about the messages compared to older cohorts.
Communicating the importance of Clean, Drain, Dry will remain imperative.
52
8. Respondents indicated that they almost always engaged in cleaning and draining behaviors.
They indicated being less likely, however, to wash their boat with a pressure washer or hot
water. This pattern of findings was repeated when respondents were presented with questions
asking about their perceived effectiveness of Clean, Drain, Dry, and the perceived difficulty
associated with these behaviors. Pressure washing and the use of hot water are behaviors that
require additional effort. Not all boaters will have access to a pressure washer and washing
watercraft with hot water is likely perceived to be cumbersome. Cleaning stations with
pressure washers or hot water would help to address this issue.
9. While respondents expressed some ambivalence concerning the frequency of other boaters’
Clean, Drain, Dry behavior, they indicated feeling a personal obligation to Clean, Drain, Dry. The
sentiment of “personal obligation” was also reflected in the injunctive norm message
experiment which elicited on of the one of the highest values in terms of the perceived
effectiveness of the message for encouraging Clean, Drain, Dry. Messages emphasizing the
sentiment of personal ownership and personal obligation to protect the resource are
compelling.
10. A quarter of respondents indicated that, on occasion, they are unable to engage in Clean, Drain,
Dry. Of these, the most commonly reported reasons were not having access to cleaning stations,
crowding at boat ramps, and the perception that others aren’t undertaking these behaviors.
While crowding at boat ramps might point toward issues of capacity, the absence of cleaning
stations is something agencies can begin to directly address. The perception of others not
undertaking the behavior is prevalent and was manifested in several related questions
throughout the questionnaire. The weaker performance of messaging containing the descriptive
norm treatment (i.e., the suggestion that the majority of the state’s boaters Clean, Drin, Dry)
further underlies the challenge. The installation of cleaning stations with clear visible
messaging kiosks would help negate the perception that few undertake Clean, Drain, Dry by
providing evidence of others taking action. The more boaters are seen to be engaging in these
actions, the more normative the behavior becomes.
11. Respondents expressed strong levels of trust in state agencies’ ability to provide timely and up
to date information about AIS and manage AIS within their state. While generally expressing
trust in state agencies (means of four on the five point scale), tournament anglers, hunters,
cabin cruiser/center console boat owners, and younger respondents scored consistently scored
lower than other groups. It is likely that tournament anglers and hunters (who are also likely
cabin cruiser/center console boat owners) are more guarded with regard to state agencies given
their consumptive orientation. In terms of younger respondents expressing less trust in state
agencies, this finding is contrary to past work illustrating the younger cohorts tend to hold a
stronger pro-environmental orientation that also has them expressing more favorable attitudes
toward public natural resource management agencies compared (Jones et al., 2003; Rasch,
2021). While statistically lower, managerially the variation is minor.
12. A quarter of respondents indicated that, on occasion, they are unable to engage in Clean, Drain,
Dry. Of these, the most commonly reported reasons were not having access to cleaning stations,
crowding at boat ramps, and the perception that others aren’t undertaking these behaviors.
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7.0 REFERENCES
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