Ecological Consequences of Marine Debris: Understanding Large-Scale Species Transport on Tsunami Debris and Research Priorities in Oregon

AN ABSTRACT OF THE THESIS OF

Reva Gillman for the degree of Master of Science in Marine Resource Management presented on September 5, 2018.

Title: Ecological Consequences of Marine Debris: Understanding Large-Scale Species Transport on Tsunami Debris and Research Priorities in Oregon

Abstract approved: ______Jessica A. Miller

The release of marine debris into the oceans and seas is a global issue of growing concern. These materials are harmful to marine environments and can also transport non-native species to novel habitats. Non-native species floating on marine litter is one of the lesser known impacts associated with marine debris. In fact, nearly 300 living coastal marine species traveled thousands of kilometers on debris items from the 2011 Great East Japan Earthquake and tsunami and reached the Hawaiian Archipelago and North American coast. It is unclear if marine debris provides a novel transport vector that transports additional species or simply an assemblage similar to one transported on other known vectors, such as hull fouling, ballast water, and aquaculture. Therefore, I characterized the distributional, environmental, and life history traits of the species identified on Japanese tsunami debris with (n=36) and without (n=61) prior transport on known anthropogenic vectors to determine if there are distinct traits associated with species that are

transported on anthropogenic vectors. A more detailed comparison of species traits was then completed among the four, most commonly reported prior vectors ballast water, hull fouling, aquaculture, and natural rafting and secondary spread (defined as the transport of organisms through drifting currents, where the species are directly in the water column, or traveling on floating natural rafts), to characterize traits that may make species more amenable to transport on specific vectors. I used

Non-Metric Multidimensional Scaling ordinations, Multi-Response Permutation

Procedures, and Indicator Species Analyses. Species with prior anthropogenic transport were more commonly on hardpan and artificial substrates, in temperate reef and fouling ecosystems, at cold water temperatures, suspension feeders, had prior invasion history, and exhibited a greater salinity tolerance than species without prior anthropogenic transport. Ballast water species were more commonly in areas with warm temperate, subtropical, and tropical water than the species without prior ballast water transport. Species with prior aquaculture transport were in flotsam, kelp forests, occur in cold and cool temperate waters more often than the species without prior aquaculture transport. Natural rafting and secondary spread species occurred more often in pelagic, cold, and saltier waters than the species with no prior natural rafting and secondary spread. Overall, I found the species with prior anthropogenic transport have the ability to colonize on artificial substrates and live in fouling ecosystems, which has obvious implications for the transport potential of these species. They also have a high tolerance to environmental stressors such as a range of salinity, which can facilitate successful species transport. In this work I

identified traits that may increase the tendency for coastal invertebrates to travel on human-mediated transport vectors, and can thus increase our scientific understanding of species dispersal.

Non-native species transport is only one of many recognized risks associated with marine debris. Research on ocean debris is ongoing, yet many of the impacts are unknown. There is a need for more research to understand the impacts of marine debris and to encourage the prevention and reduction of marine pollution.

Therefore, a survey was distributed to Oregon stakeholders with an ultimate goal to prioritize and rank marine debris research topics relevant to Oregon. The survey was sent out to interested citizens, citizen scientists, researchers, and managers. With limited available funding and the need to bridge knowledge gaps, the prioritization and ranking of marine litter research topics can help to improve research efficacy and applicability. After surveying 116 participants, three marine debris research priorities emerged as highest priority for Oregon stakeholders surveyed: 1) marine debris impact on Oregon’s ecosystems, 2) microplastics impact on Oregon’s ecosystems, and 3) investigate best approaches for working with industry to reduce plastic waste, especially packaging. These results highlight general concern for ecological impacts and can help to prioritize future marine debris research efforts in

Oregon. In addition, research on marine debris as a vector for non-native species was a lower priority topic, suggesting this concern may not fully be addressed unless it becomes a larger, increasingly documented issue.

Ecological Consequences of Marine Debris: Understanding Large-Scale Species Transport on Tsunami Debris and Research Priorities in Oregon

by Reva Gillman

A THESIS

submitted to

Oregon State University

in partial fulfillment of the requirements for the degree of

Master of Science

Presented September 5, 2018 Commencement June 2019

Master of Science thesis of Reva Gillman presented on September 5, 2018

APPROVED:

Major Professor, representing Marine Resource Management

Dean of the College of Earth, Ocean, and Atmospheric Sciences

Dean of the Graduate School

I understand that my thesis will become part of the permanent collection of Oregon State University libraries. My signature below authorizes release of my thesis to any reader upon request.

Reva Gillman, Author

ACKNOWLEDGEMENTS

The author expresses sincere appreciation to her academic advisor Dr.

Jessica Miller for her unwavering support through every step of the process, and for her outstanding dedication of time and energy to this project. She would also like to thank her committee members Dr. Bruce McCune, Dr. Ana Spalding, and Dr. Steven

Dundas. The knowledge and guidance of this committee was invaluable. In addition to the committee, the author would like to express appreciation to the North Pacific

Marine Science Organization (PICES), Oregon State University (OSU), and the College of Earth, Ocean, and Atmospheric Sciences (CEOAS) at OSU for their financial support.

Critical support with field collections of Japanese tsunami debris biota was provided by John Chapman, Allen Pleus, Jesse Schultz, Thomas Murphy, Ruth

DiMaria, as well as many volunteers in Washington, Oregon, and Hawaii. The author also wishes to acknowledge the many, many scientists who contributed to the identification of the marine invertebrates. The author is grateful to Jocelyn Nelson,

Michio Otani, Shigeo Kawaguchi, Kiyotaka Matsumura, and Janson Wong for their assistance with the literature review and population of the species database.

The author would like to express gratitude to Nir Barnea, Matthew Coomer, and the practitioners who participated in the pre-workshop survey for providing their time and data to the survey work. Sincere appreciation goes to Nir and Matt for graciously allowing the author to further distribute the survey. The survey research would not have been possible without their help. Oregon Sea Grant staff

member at Hatfield Marine Science Center, Renee Fowler, also provided critical support in the distribution of the survey. Additionally, the author thanks folks in the

Marine Resource Management program, the Oregon Sea Grant Volunteers, and the

Hatfield Marine Science Center community, visitors, and other participants who gave their time and feedback to take the survey.

The support of CEOAS and the Marine Resource Management (MRM) program has been unwavering. The author expresses heartfelt thanks to Flaxen

Conway, Lori Hartline, and Robert Allan for their investment in the author’s success.

Huge thank you to Tom Hurst, Thomas Murphy, and Angie Munguia for all their feedback during lab meetings. Also, the author is grateful to Susan Rowe from the graduate writing center for all of her amazing help. The author would like to recognize her family, friends, fellow MRMers, and colleagues for additional support,

Angie Munguia for lending her computer which made PC-ORD analysis possible in

Corvallis, and Praveen Venkatachala for his moral support through every step of the author’s graduate journey, including a supply of good food. Lastly, the author would like to thank her dog, Ruby, for being her loyal thesis-writing assistant and providing much-needed breaks to go to the park. Thank you!

CONTRIBUTION OF AUTHORS

Jocelyn Nelson, Michio Otani, Shigeo Kawaguchi, Kiyotaka Matsumura, and

Janson Wong assisted in the literature review and population of the Japanese

Tsunami Marine Debris (JTMD) species database used in Chapter 2. Previous work

(Miller et al. 2018) also analyzed the JTMD species database. Specifically, Miller et al.

(2018) analyzed 93 JTMD species and identified traits that separate species with and without prior invasion history. Chapter 2 builds upon Miller at al. (2018) by using a similar framework for analysis but asking different questions. In Chapter 2, my analysis focused on traits that separate species with and without prior anthropogenic transport in order to identify traits that may make species more able to travel on human-mediated vectors. Additionally, my analysis included 97 JTMD species (including cryptogenic species).

Nir Barnea, the Pacific Northwest Regional Coordinator of the NOAA Marine

Debris Program, as well as Matthew Coomer from NOAA Marine Debris Program developed the list of marine debris research topics, distributed and compiled the results from the pre-workshop survey, and graciously allowed the author to further distribute the survey.

TABLE OF CONTENTS

Page

Chapter 1: Introduction: Debris in the Ocean……………………………………………………… 1

Chapter 2: Rafting Across the Pacific on Tsunami Debris…………………………………….11

2.1 Introduction ……………………………………………………………………………………..11

2.2 Methodology ……………………………………………………………………………………20

2.3 Results …………………………………………………………………………………………..…29

2.4 Discussion ……………………………………………………………………………………..…43

Chapter 3: Marine Debris in Oregon: A Survey of Research Priorities………….…..…58

3.1 Introduction ……………………………………………………………………………….…….58

3.2 Methodology ………………………………………………………………………….………..63

3.3 Results ………………………………………………………………………………………………68

3.4 Discussion………………………………………………………………………………………….75

Chapter 4: Conclusion …………………………………………………………………………..……………84

Bibliography ………………………………………………………………………………………………..……..88

Appendices …………………………………………………………………………………………………………97

Appendix A. JTMD Materials..………………………………………………………….……...98

JTMD Database Standardized Search Protocol……………………………105

Vector Detailed Descriptions………………………………………………………106

Appendix B. Marine Debris Survey Materials.……………………………….………..109

Marine Debris in Oregon Survey ………………………………..…….………..109

Online Survey Example ………………………………..…………………..………..112

LIST OF FIGURES

Figure Page

1. Examples of JTMD ……………………………………………………………………………… 15

2a. Diagram of anthropogenic vs. non-anthropogenic transport……………... 22

2b. Diagram of the four vector specific comparisons ……………………………….. 22

3. Venn diagram of species overlap in four vector groups ……………………… 25

4. The percent of Japanese Tsunami Marine Debris species per phyla……. 30

5. The number of JTMD species documented per transport vector…………. 31

6. The reported trophic level of 103 (out of 105) JTMD species ..……………. 31

7a. Ordination of 97 JTMD species based on their documented geographic distribution. Species with prior anthropogenic transport and species without prior anthropogenic transport in geographic space……….……………………….………………………….………………………….….....…… 33

7b. Ordination of 97 JTMD species based on their documented geographic distribution. Graphs of the four vector group comparisons.. 34

8a. Ordination of 97 JTMD species based on environmental and life history traits. Anthropogenic traveler species and non-anthropogenic traveler species in trait space..……………………………………..…….……………….. 39

8b. Ordination of 97 JTMD species based on environmental and life history traits. Graphs of the four vector group comparisons.……………………….…. 41

9. Marine debris survey participants by group ……………………………………….. 68

10. Total number of blank, unanswered questions for all respondents….…. 69

11. Average (± SE) priority rank score by marine debris topic number for all participants.………………………………………..………………………………………….. 70

12. Average (± SE) priority ranking scores by marine debris topic number, separated by the five participant groups..…………….…………………………….. 72

LIST OF FIGURES (Continued)

Figure Page

13. Total survey response composition by marine debris topic……….….……. 74

LIST OF TABLES

Table Page

1. The JTMD species with prior vector transport (n = 41).………………………… 24

2. Pearson correlations with ordination axes: correlations between axis scores and the JTMD species’ geographic distribution from the NMS.…. 33

3. Pearson correlations with ordination axes: correlations between axis scores and the JTMD species’ trait distribution from the NMS.……….…... 38

4. Anthropogenic traveler traits……………………………….…………………………...… 41

5. Traits that were positively associated with the four vector groups…….… 42

6. The 21 marine debris research topics present in the questionnaire.....… 64

LIST OF APPENDIX FIGURES

Figure Page

B1. Mobile Survey Example.…………………….………………………………………..……. 113

B2. Average priority rank by marine debris topic for pre-workshop survey (n = 16) and the online/on-site survey questionnaire (n = 100)…....…… 114

LIST OF APPENDIX TABLES

Table Page

A1. Traits in JTMD Invertebrate Species database……….…………………………….. 98

A2. JTMD Invertebrate Species list ………………………………………………….…..…….. 102

A3. Hull Fouling Traits ………………………..……………………..………………………………. 106

A4. Ballast Water Traits …………………………………………..………………………………... 107

A5. Aquaculture Traits …………………………………………..……………………………..…... 107

A6. Natural Rafting/Secondary Spread Traits …………………………………..………... 108

DEDICATION

To my grandmother who received her Master’s during a time when few women did. Thank you for all of your support, for always believing in me, and for teaching me the value of higher education.

Chapter 1: Debris in the Ocean

"Think about it. Why would you make something that you're going to use for a few minutes out of a material that's basically going to last forever, and you're just going to throw it away. What's up with that?" – Jeb Berrier, BagIt Movie

It is sometimes a challenge to imagine a world without plastics. A miracle material that we depend on for a great deal, plastics have made modern life possible. They are the essence of convenience: lightweight, yet durable, and disposable. Plastics are used in food packaging, cars, electronics, medical devices, houses, agriculture and clothing (Plastics Europe 2018). Plastics are everywhere. Our overuse of plastics, however, can have great consequences and some plastic use outweighs its convenience. Plastics are frequently used to make single-use items, which are thrown away after one use. Because it is durable and non-biodegradable, it persists. Plastic waste that is produced all over the world ends up in the ocean, where its impacts are largely unknown. We depend on our ocean as a key component of the global climate, to produce oxygen and absorb carbon. We depend on the ocean as a source of food, a place to recreate, a place of beauty and biodiversity. The health of our ocean’s ecosystems and ocean economy is threatened by the presence of plastic waste and other debris.

Marine debris is defined as “any persistent solid material that is manufactured or processed and directly or indirectly, intentionally or unintentionally, disposed of or abandoned into the marine environment or the Great 2

Lakes” (NOAA, 2015). The disposal of marine debris into the oceans and seas is a global issue of growing concern. Marine debris consists of waste such as soda cans, plastic bottles, buckets, packaging materials, polystyrene foam, bags/film, derelict fishing gear (nets, lines, buoys, traps), and abandoned vessels (Eriksen et al. 2014).

Plastic pollution has reached a global scale and is present in almost every environment of the world (Barnes 2009, Galgani 2015). The ocean, which receives both land-based and ocean-based litter, is especially vulnerable (Lebreton et al.

2017, Galgani et al. 2015, Araujo & Costa 2007, Rech et al. 2014). However, most marine debris (about 80%) originates on land (Derraik 2002) and most marine debris is plastic (Thiel et al. 2013).

The quantities of marine debris are increasing as are the problems related to marine debris (Barnes et al. 2009, Ryan et al. 2009). It was estimated that in 2010, the global input of plastic waste to the ocean was 4.8 to 12.7 million metric tons, and this amount is expected to increase annually (Jambeck 2015). Marine debris is very harmful to marine environments (Derraik 2002, Gregory 2009). Plastic pollution causes harm to marine animals through entanglement and ingestion (Gall &

Thompson 2015), toxic human health concerns (Galloway 2015, Newman et al.

2015), navigation hazards, transport of non-native species, and severe damages to fishing, tourism, and natural areas (Gregory 2009, Thiel & Gutow 2005, Kiessling et al. 2015). In recent decades, due to increasing evidence for marine debris-related issues and public awareness, there have been campaigns against single-use plastics, for example plastic bag bans in grocery stores, and the removal of plastic

3 microbeads from personal care products (e.g. http://storyofstuff.org/, http://www.beatthemicrobead.org/).

Coastal marine species floating on marine litter to locations outside of their native range is one of the lesser known potential impacts associated with marine debris (Rech et al. 2018). This issue, in contrast to images of plastic ingestion by marine animals and microplastics, attracts less public and media attention. There have been frequent reports of organisms floating on anthropogenic marine debris

(Goldstein et al. 2014, Kiessling et al. 2015, Hoeksema et al. 2012, Carson et al. 2013,

Barnes 2002). The frequency of coastal interceptions of debris with marine species is unknown and their potential impact on coastal ecosystems and marine biodiversity is not yet well understood (Rech et al. 2016). However, the environmental and economic threats caused by invasive species to marine environments are well known; they can put native species at risk, reduce native biodiversity, and threaten marine economies, to name a few (Pimentel et al. 2005, Shiganova 1998, Ricciardi

1998, Cohen & Carlton 1995).

Due to increasing amounts of plastics and anthropogenic marine debris in the ocean (Eriksen et al. 2014, Barnes 2009, Jambeck 2015), there are more global sources of nonbiodegradable materials available for marine organisms to colonize.

There is evidence that climate change may be increasing the severity of storms that are more efficient at ejecting debris into the ocean (Baldini et al. 2016, Sobel et al.

2016). These changes could increase the occurrence of ocean rafting that may result in an increased frequency of species invasions (Carlton et al. 2017). The next section

4 discusses an ocean rafting event that transported species on Japanese tsunami debris, which is the subject of the second chapter of the thesis.

Japanese Tsunami Debris Rafting Event

A recent natural disaster, the 2011 Great East Japan Earthquake and subsequent tsunami, launched an extraordinary amount of marine debris into the

Pacific Ocean, which created a large-scale, unique rafting event. This field of tsunami debris, which included vessels, docks, buoys, and fish totes, traveled across the

Pacific Ocean with living coastal invertebrates, algae, and two species of fish (Carlton et al. 2017). Overall, since 2012, nearly 300 living Japanese species were documented arriving on 634 Japanese tsunami marine debris (JTMD) objects that traveled thousands of kilometers across the Pacific Ocean to reach the North

American and Hawaiian coastlines (Carlton et al. 2017).

Since 2012, taxonomists around the world have identified nearly 300 species associated with JTMD. In order to expand our understanding of the species associated with JTMD, the majority of which had not been observed rafting before this event, a database that included geographic, environmental, and life history information for these JTMD species was developed. The database compiled available information on the JTMD species using both English and Japanese literature. The database also contains information on prior transport vectors (any reported methods of transport before the Japanese tsunami rafting event) for the JTMD species. Transport vectors are the mechanisms that allow species to move outside of

5 their native range, and are an important aspect of species dispersal. In this study, I analyze the life history traits for species that have traveled on common transport vectors, including ballast water, hull fouling, aquaculture, and rafting. By taking a closer look at the prior methods of transport of the JTMD species, I aim to increase understanding of species transport through characterizing the geographic, environmental, and life history features that may be associated with specific transport vectors. The goal of this study is to characterize the traits of anthropogenic travelers (species with prior documented dispersal through human-mediated transport), and compare with species with no prior human-mediated transport, in order to make a distinction between anthropogenic and natural vectors.

As I learned more about marine debris as a vector for non-native species, I became more interested in the local management of this issue. This led me to look into the way Oregon prioritizes and manages marine debris issues. Therefore, I also conducted a survey to understand how people prioritize marine debris issues and to determine the relative importance of marine debris as a vector in this landscape of marine issues. The next section introduces the survey I conducted, which is the topic of chapter three.

Marine Debris in Oregon: A Survey of Research Priorities

Research on the topic of ocean debris is ongoing, and many of the impacts are unknown. There is a need for more marine debris research, in order to understand the potential and realized impacts and to encourage the prevention and reduction of

6 marine pollution. Therefore, I distributed a survey to Oregon stakeholders that contained a list of marine debris research topics. The goal of the survey was to prioritize and rank marine litter research topics that are relevant to Oregon, and I included interested citizens, citizen scientists, researchers, and managers. A related goal was to identify varying priorities among groups, if any, in order to prioritize future prevention efforts. The survey was distributed in order to answer four questions:

1. How can we help focus marine debris research efforts in Oregon, even though extensive knowledge gaps exist? 2. Which marine debris research topics are high priority for Oregon stakeholders? 3. What differences exist in priorities for marine debris research among interested citizens, researchers, citizen scientists, and managers? 4. Is conducting research on marine debris as a vector for non-native species a high priority for Oregon stakeholders?

Building on this work, I hope to help focus marine debris research efforts in

Oregon. With limited available funding and the need to bridge knowledge gaps, the prioritization and ranking of marine litter research topics can help to improve research efficacy and applicability.

Thesis Organization

This thesis is organized into four chapters. The first chapter describes the context and introduces the two studies: the JTMD species study and the marine debris survey study. Chapter two presents the JTMD species study which I intend to submit to the journal Marine Pollution Bulletin, an international journal for marine

7 environmental scientists, engineers, administrators, politicians and lawyers. Chapter three includes the marine debris survey introduction, methods, results, and discussion of the survey work. Chapter four discusses overall findings, limitations, future directions, and recommendations based on the two studies.

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Chapter 2

Rafting Across the Pacific Ocean on Tsunami Debris: the Hitchhikers and their Prior Transport History

2.1 Introduction

Hundreds of living coastal marine species traveled thousands of kilometers across the Pacific Ocean to reach the Hawaiian Archipelago and North American coast on debris items from the 2011 Great East Japan Earthquake and tsunami

(Carlton et al. 2017). The species identified on Japanese tsunami debris were studied in order to characterize the traits of species with and without prior transport on known anthropogenic vectors. This was done in order to identify traits that may make species more amenable to transport on anthropogenic vectors.

Passive ocean transport of floating substrate with attached biota, or dispersal via rafting, has helped shape the biodiversity of island ecosystems (Thiel & Haye

2006). These rafts, which include materials floating on the sea surface, can drift to new locations outside the native range of rafting species and upon arrival can result in the establishment of new populations (Thiel & Gutow 2005b). Rafting can be an important mechanism for the dispersal of marine species (Thiel & Gutow 2005b,

Barnes and Fraser 2003, Bryan et al. 2012). Species have long been transported on naturally occurring rafts composed of ice, algae, wood, seeds, and pumice (Thiel and

Gutow 2005a, Bryan et al. 2012). Records of large ‘floating islands’ transporting terrestrial vertebrates have been recognized since medieval times (Van Duzer 2004).

Fossil evidence of marine organisms found within fossilized driftwood suggest that

12 rafting may have been an important dispersal process in paleo-oceans (Simms 1986,

Arua 1991). In recent decades, the natural process of rafting has been enhanced by anthropogenic debris composed primarily of non-biodegradable plastics, foam, synthetic rubber, and fiberglass (Derraik 2002; Barnes et al. 2009). There have been frequent reports of organisms floating on anthropogenic marine debris (Goldstein et al. 2014, Kiessling et al. 2015, Hoeksema et al. 2012, Carson et al. 2013, Barnes

2002) but the species impact on coastal ecosystems and marine biodiversity is not yet understood (Rech et al. 2016). However, the threats caused by invasive species to marine environments are well known; they can put native species at risk through competition and predation, cause biodiversity loss, threaten economically important fisheries and aquaculture species, and cause many other serious economic and environmental issues (Pimentel et al. 2005, Shiganova 1998, Ricciardi 1998, Cohen &

Carlton 1995).

The transport of coastal species on marine debris is distinct from other well- known anthropogenic vectors. Rafts are slow-moving vectors that can transport coastal organisms long distances (>1000km) (Barnes and Fraser 2003, Bryan et al.

2012, Carlton et al. 2017), over long time-scales with more random distributions influenced by currents (Lebreton and Borrero 2013). Commercial vessels move relatively rapidly (20 - 25 knots), which can impact the attachment, retention, and recruitment of biofouling species (Coutts et al. 2010). In contrast, marine rafts travel at much slower speeds (1-3 knots). Rafts may thus provide species acclimatization time to adjust to changing environmental conditions during long voyages (Carlton et

13 al. 2017). Large rafts in particular can transport sizeable communities of mostly adult organisms compared with ballast water, which transports primarily planktonic stages of species (Carlton and Geller 1993).

Human-mediated vectors, which travel faster than slow-moving rafts, can transfer non-native marine species on ships internally, externally, or as cargo on the ship. As an internal shipping vector, ballast water tanks can transport non-native species. Ships’ ballast water is a very effective dispersal mechanism of coastal marine species and is associated with one-third of the hundreds of documented marine introductions worldwide (Hewitt and Campbell 2010). Ballast water is one of the primary vectors for the translocation of non-indigenous zooplankton (DiBacco et al. 2011).

Organisms can also travel externally on ships through hull fouling. Hull fouling is a potent method of transport for coastal species (Hewitt and

Campbell 2010). Even though the mean number of organisms transported per ship has decreased over time because of faster ship speeds, shorter port time, and antifouling measures (Carlton 1985), hull fouling vector strength is comparable to ballast water for reported marine introductions among all vectors worldwide (Hewitt and Campbell 2010). Successful hull fouling organisms, such as barnacles and mussels, tend to have high attachment strength and a low drag coefficient (Murray et al. 2012).

In addition, species can travel as shipping cargo through aquaculture activities. Many non-indigenous marine species introductions have resulted from

14 importing new species for commercial aquaculture purposes but also from associated ‘hitchhiking’ species accidentally transferred along with the target species

(Grosholz et al. 2015). Species used for aquaculture purposes are also likely to be hardier, faster-growing and larger bodied than their native analogs (Grosholz et al.

2015).

Japanese Tsunami Debris Megarafting Event

The 2011 Great East Japan Earthquake and subsequent tsunami launched an extraordinary amount of marine debris into the Pacific Ocean, which created a large- scale, unique rafting event. This tsunami debris traveled across the Pacific Ocean with living coastal invertebrates, algae, and two species of fish. Overall, since 2012, nearly 300 living Japanese species from 16 phyla were documented arriving on 634

Japanese tsunami marine debris (JTMD) objects which traveled thousands of kilometers across the Pacific to reach the North American and Hawaiian coastlines

(Carlton et al. 2017).

The tsunami rafting event was unprecedented in that it was the longest and farthest recorded transoceanic survival and dispersal of coastal species by rafting

(Carlton et al. 2017). Prior to this event, understanding of transoceanic rafting events was limited by the lack of observations of debris transporting coastal communities across the ocean. The JTMD event presented a rare opportunity to investigate the release of anthropogenic marine debris and associated rafting species with the unique opportunity to know where the JTMD came from and when it was ejected from the coastline. This event provided an opportunity to observe and

Figure 1. Examples of JTMD. Top left: 70 ft Japanese dock reached Agate Beach, Oregon in June 2012 covered in > 100 different living species from Japan. Top right: refrigerator from the tsunami with living organisms attached. Bottom right: Living juvenile striped beakfish, Oplegnathus fasciatus, arrived on the Washington coast in March 2013 after travelling more than 5,000 miles in a small Japanese fishing boat. Bottom right: Japanese skiff from the tsunami with living organisms attached.

document the JTMD species transported transoceanically to North American and

Hawaiian coastlines. Out of the 289 species documented on JTMD, none were previously reported to have rafted transoceanically between continents (Carlton et al. 2017). The JTMD rafts were a diverse assortment of anthropogenic debris items ranging from small plastic fragments to buoys, boats, fishing vessels, and large docks

(Carlton et al. 2017). Building wood and some trees made the transoceanic crossing but its arrival was constrained within 2013 -2014; the lack of later arrivals was

16 potentially due to the degradation of wooden JTMD by wood-boring shipworms

(Carlton et al. 2017). It is plausible that most of the natural materials were not able to make a transoceanic crossing because they degraded or became waterlogged and sunk.

There was an international effort to document the JTMD event through debris response, species collections, and taxonomic identifications. There was also an extensive effort to study the biota on Japanese tsunami debris (Calder et al. 2014;

Carlton et al. 2017; Miller et al. 2018; Therriault et al. 2018, Ta et al. 2018, Treneman et al. 2018). The debris that washed up on shorelines of North America and the

Hawaiian Archipelago was classified as JTMD by a suite of criteria, including: (1) official identification, such as serial or registration numbers that were linked by the

Consulate of Japan to objects lost during the 2011 tsunami; (2) biofouling marine life that was representative of the Tōhoku region, the portion of the Japanese coast hit hardest by the tsunami; (3) post-and-beam lumber with standard Japanese dimensions; or (4) a combination of these criteria (Carlton et al. 2017). JTMD that landed on coastlines of Hawaii, British Columbia, Alaska, Washington, Oregon, and

California were sampled for invertebrates, algae, and fish between June 2012 and

July 2016. These species were then preserved and sent to 80 experienced taxonomists in 13 countries to identify the specimens (Carlton et al. 2017).

The JTMD species have been documented through a database of life history, distributional, and environmental species traits. The database contains a subset (n =

105) of the 300 species identified, i.e., the invertebrate species with adequate life

17 history information available in the literature. Its purpose is to record the biodiversity of JTMD species, provide an ecological synthesis, and understand the potential for invasion by JTMD species. The database includes 65 species previously unknown to the Northeast Pacific. The geographic distribution of the JTMD species is cosmopolitan, with species ranging from the Southern Ocean to the Arctic, but most are native to the temperate Northwest Pacific. A clear impact that JTMD species can have in North America and the Hawaiian Archipelago is by introducing species that become established and cause damage to coastal ecosystems. For example, the shipworm, Teredo navalis, was one of the species documented on JTMD that arrived along Northeastern Pacific coastlines, but it has a history of invasion in the United

States prior to the tsunami event. T. navalis was introduced to the San Francisco Bay and, since the early 1990s has caused serious damage to ships and docks (Cohen and

Carlton 1995). Currently, damages are estimated to be about $205 million/year in

San Francisco Bay (Pimentel et al. 2005).

The JTMD species database has been used in previous studies to rank species invasion risk (Therriault et al. 2018) and to compare the distributional, environmental, and life history traits of the species with and without prior invasion history (Miller et al. 2018). The database also contains information on prior reported transport history for the species before the Japanese tsunami rafting event.

Characterizing the distributional, environmental, and life history traits of these JTMD species associated with these vector groups has not been done, and is an important piece in understanding species transport.

The three most prevalent vectors in the database are transport through hull fouling, ballast water, and aquaculture and fisheries trade. While target species are intentionally introduced for aquaculture and fisheries enhancement, no other vectors are species specific – some mechanisms, such as ballast water and hull fouling, are likely to transport an entire species assemblage (Hewitt and Campbell

2010). These transport mechanisms have restrictions that influence a species’ ability to successfully enter and survive the voyage (Hewitt et al. 2007). This suggests that groups of species with ecological and life history features may be associated with specific transport vectors (Hewitt and Campbell 2010). For example, ballast water primarily transports planktonic stages of species, and often includes pelagic species

(Carlton and Geller 1993). In contrast, hull fouling transports species that are sedentary, sessile, benthic, or associated with these communities (e.g. living on, in, or between other organisms) (Minchin and Gollasch 2002).

Because species that have been transported through ballast water, hull fouling, and aquaculture vectors have traits and adaptations that make them suitable to transport via their associated vector, we expect differences among their life history traits. Previous studies have examined life history characteristics of introduced and cryptogenic species to determine vector associations, and to find the relative contribution of vectors to the translocation of invasive marine species

(Hewitt 1999, 2004, Hewitt and Campbell 2010).

Previous work (Miller et al. 2018) also analyzed the JTMD species database.

Specifically, Miller et al. (2018) analyzed JTMD species and identified traits that

19 separate species with and without prior invasion history. This chapter builds upon

Miller at al. (2018) by using a similar framework for analysis but asking different questions. In this study, we analyze the life history traits for species that have traveled through ballast water, hull fouling, aquaculture, and rafting. By grouping

JTMD species by prior reported modes of transport, we can characterize the ecological and life history features that may make species more amenable to transport on specific transport vectors and increase our understanding of species transport. The overall goal of the study is to characterize the traits of anthropogenic travelers, defined here as species with prior documented dispersal through human- mediated transport such as shipping and activities of aquaculture and fisheries, and compare with species with no prior human-mediated transport. Given the focus on differences between anthropogenic and natural vectors, we make several specific comparisons. First, we compare species that have 1) prior, reported travel on rapid, anthropogenic vectors and 2) species that have travelled on slow, naturally- occurring rafts or spread secondarily via natural processes after arriving in a novel habitat. Second, we complete four vector-specific species comparisons: 1) hull fouling vs. non hull fouling species; 2) ballast water vs. non ballast water species; 3) aquaculture vs. non aquaculture species; and 4) natural rafting or secondary spread vs. no prior natural rafting or secondary spread species.

2.2 Methods

Compilation of the JTMD Species Database

An international team of researchers developed a JTMD-associated invertebrate database, describing life history, distributional, and environmental traits of organisms that could be identified to species. We compiled information using a standardized search protocol (Appendix A) of primary publications, online resources, and databases written in both English and Japanese. The database, which includes information on the biology, reproduction, ecology, native range, vector history and invasion history of these species, is publicly available through the

Smithsonian Environmental Research Center’s National Exotic Marine and Estuarine

Species Information System (http://invasions.si.edu/nemesis/) (Nelson et al. 2016).

Database Conversion

We converted the online JTMD invertebrate database to a format that was more amenable to quantitative analysis by reducing the categories and condensing the qualitative information contained to categorical data. We only included species and variables with adequate information to perform quantitative analysis (Table A2). For a small amount of the data (< 1% of the cells), default categories were assigned for several species in order to fill in missing information.

To facilitate the analysis of the vector groups, all available information on vectors was used. Vector information on initial introduction, as well as any vector information on secondary spread in non-native areas after initial introduction was

21 included. All 41 species with vector transport history have at least one vector of initial introduction, and the following five species also have secondary vector information: Asterias amurensis, Crassostrea gigas, Hemigrapsus sanguineus,

Lyrodus takanoshimensis, and Obelia longissima.

Comparing prior transport

The four most prevalent vectors in the JTMD database are hull fouling, ballast water, aquaculture and fisheries, and natural rafting/secondary spread. These four vector categories are defined as follows:

1) Hull fouling is the “transport of organisms living on, or associated with, the hulls of commercial vessels and recreational boats, including organisms ensnared on propellers” (Lee II & Reusser, 2012). 2) Ballast water is the “transport of organisms in ballast water, including species growing on the interior of ballast water tanks and in the sediment in the bottom of ballast tanks” (Lee II & Reusser, 2012). 3) Aquaculture and Fisheries is the “transport of target species and “hitchhikers” associated with enhancement of wild fisheries stocks or aquaculture” (Lee II & Reusser, 2012). 4) Natural rafting/secondary spread is the “transport of organisms through drifting currents, where the species are directly in the water column, or traveling on floating natural rafts” (Lee II & Reusser, 2012).

Figure 2a. Diagram of anthropogenic vs. non-anthropogenic transport comparison with description and number of species per group.

Figure 2b. Diagram of the four vector specific comparisons (hull fouling, ballast water, aquaculture, and natural rafting/secondary spread) with description and number of species per group. The natural rafting/secondary spread group of 17 species contains eight natural rafters and nine secondary spreaders.

The goal of this study was to characterize the traits of 1) anthropogenic travelers, defined here as species with prior documented dispersal through human-

23 mediated transport such as shipping and aquaculture/fisheries activities, and compare to 2) non-anthropogenic travelers, or the species with no prior human- mediated transport (see Figure 2a). In this study, we compared geographic distribution, environmental and life history traits of the anthropogenic travelers (n =

36) versus the non-anthropogenic travelers (n = 61). In detail, the non- anthropogenic transport group contains over half of the JTMD species (n = 56) which have no record of transport (or past mechanism of dispersal) prior to floating on

JTMD, and five species that were recorded floating on natural rafts prior to the tsunami. Next, we compared traits of the species associated with each of the four vector groups hull fouling, ballast water, aquaculture and fisheries, and natural rafting/secondary spread (See Figure 2b), to determine if JTMD species that have prior, reported transport via hull fouling, aquaculture, ballast water, or natural rafting/secondary spread (Table 1) possess different traits compared to the rest of the JTMD species without that type of prior transport. The natural rafting/secondary spread group of 17 species contains, in more detail, eight natural rafters and nine secondary spreaders. Very few species were transported on only one vector, while many were transported on multiple vectors, resulting in overlap between vector groups (Figure 3).

Table 1. The JTMD species with prior vector transport (n = 41), which were included in the quantitative analysis (n = 97). Species documented on any of the four vectors (hull fouling (HF), ballast water (BW), aquaculture (AQ), and natural rafting/secondary spread (R/S) are shown here. See Table A2 for the full species list.

Phylum Genus species HF BW AQ R/S Crustacea Ampithoe lacertosa X X X Crustacea Ampithoe valida X X X Echinodermata Asterias amurensis X X X X Crustacea Balanus glandula X X X Crustacea Balanus trigonus X X X Bryozoa Biflustra grandicella X Crustacea Caprella mutica X X X X Bryozoa Celleporella hyalina X X Bryozoa Celleporina porosissima X Crustacea Chthamalus challengeri X Mollusca Crassostrea gigas X X X Mollusca Crepidula onyx X X Bryozoa Cryptosula pallasiana X X X Cnidaria Diadumene lineata X X X Chordata Didemnum vexillum X X X X Arthropoda Endeis nodosa X X Bryozoa Exochella tricuspis X Crustacea Hemigrapsus sanguineus X X X X Mollusca Hiatella orientalis X Annelida Hydroides ezoensis X X X Mollusca Hyotissa quercinus X Crustacea Ianiropsis serricaudis X X X Crustacea Jassa marmorata complex X X X Mollusca Lyrodus takanoshimensis X X Crustacea Megabalanus rosa X X X Crustacea Megabalanus zebra X Cnidaria Metridium dianthus X X Mollusca Mytilus galloprovincialis X X X X Cnidaria Obelia longissima X X X Crustacea Paralaophonte congenera X Crustacea Parastenhelia spinosa X Crustacea Parathalestris intermedia X Mollusca Patinopecten yessoensis X X Sipuncula Phascolosoma scolops X X Bryozoa Schizoporella japonica X X Crustacea Semibalanus cariosus X Crustacea Stenothoe crenulata X X Arthropoda Telmatogeton japonicus X X Mollusca Teredo navalis X X X Bryozoa Tricellaria inopinata X X X Bryozoa Tubulipora pulchra X

Figure 3. Venn diagram of species overlap in four vector groups (hull fouling, ballast water, aquaculture and fisheries, and natural rafting/secondary spread). Tan circle represents species reported hull fouling (n = 32), blue for ballast water species (n = 21), green for aquaculture/fisheries species (n = 24), and pink for natural rafting/secondary spread species (n = 17). A total of 41 species are reported on the four vectors, with the numbers showing how many species fall under each vector combination. For instance, the white “5” in the center where all four circles overlap represents the five species that have been reported on all four vectors. The vector combination not shown in this diagram are the two species that have been reported on only hull fouling and aquaculture.

Species synthesis In order to better understand the life history variation present among the

JTMD species, we compiled summaries of JTMD species across different categories

26 of interest for synthesis. We used 105 invertebrate species for synthesis (Table A2).

All species were identified down to the lowest taxonomic level, but in two instances, we included species complexes (Jassa marmorata-complex and Stenothoe crenulata- complex). The summarized information includes phyla, native geographic range, invasion history, transport history, and trophic level.

Quantitative analysis The information was transformed into binary and categorical data for analysis using PC-ORD Version 7.0 (McCune & Mefford, 2016). We used the invertebrate species with adequate data coverage for quantitative analysis (8 species with insufficient data were removed) (Table A2), which left 97 species in the database. The following 8 species were removed for the quantitative analysis:

Tectura emydia, Hippothoa imperforata, Placiphorella stimpsoni, Bankia bipennata,

Havelockia versicolor, Hydrodendron gracile, Gromia oviformis, and Cibicides lobatulus. We used 108 variables, including the species' native marine realm and region (Spalding et al. 2007), prior invasion history, temperature and salinity ranges, reproductive and developmental characteristics, mobility, depth regimes, habitat, ecosystems, substrates, and trophic status (See Table A1). The geographic distribution information (native realm and region) was analyzed separately from the environmental and life history traits information. We chose this approach because we were interested in the variation of the environmental and life history traits independent of geographic distribution. In this study we used the Miller et al. 2018

27 geography ordination results, but instead of grouping species by invasion history we grouped species by prior vector (Figure 7a, 7b).

Anthropogenic Transport Comparison

First, we characterized trait variation within the JTMD species pool using

Nonmetric Multidimensional Scaling (NMS), which is an ordination technique based on ranked distances between species. NMS is an iterative process to rank and place n entities on k dimensions (axes) that minimize the stress of the k-dimensional configuration (McCune & Grace, 2002). NMS is an effective ordination method for ecological community data, and often the method of choice for graphical representations of community relationships, as it avoids the assumption of linear relationships among variables (Clarke & Ainsworth, 1993; McCune & Grace, 2002).

For this analysis, Sorensen (Bray-Curtis) distance measure was used. A measure of

“stress”, which is measured on a scale of 0 to 100, describes the measure of departure from monotonicity. Second, using a Multi-Response Permutation

Procedure (MRPP), we tested the hypothesis that JTMD species classified as the anthropogenic travelers (n = 36) possess a significantly different suite of distributional, environmental, and life history traits than the non-anthropogenic travelers (n = 61, see Figure 2a). The MRPP is a non-parametric procedure that tests the hypothesis of no difference between two or more groups, and does not require certain assumptions, such as multivariate normality and homogeneity of variances

(McCune & Grace, 2002). The MRPP generates a weighted mean within-group distance (δ) and a chance-corrected within group agreement test statistic (A). We used the Sorensen (Bray-Curtis) distance measure for the MRPP, same as in the

NMS. Third, we completed an Indicator Species Analysis (ISA) to identify any distributional, environmental, and life history traits that were responsible for group separation when identified using the MRPP.

Vector specific comparison

Next, we compared the vector groups in order to characterize distributional, environmental, and life history traits associated with each specific vector (hull fouling, ballast water, aquaculture and fisheries, and natural rafting/secondary spread). We performed multiple comparisons of each of the four vector groups (see

Figure 2b), to determine if JTMD species that have transported via hull fouling, ballast water, aquaculture and fisheries, or natural rafting/secondary spread possess a significantly different suite of distributional, environmental, and life history traits than the rest of the JTMD species without that type of prior transport. Following the same procedure as in the above comparison between anthropogenic and non- anthropogenic transport, we used a MRPP to determine if groups were significantly different, followed by an ISA (when applicable) to identify any distributional, environmental, and life history traits that were responsible for group separation when identified using the MRPP, to do multiple vector comparisons and test the following four hypotheses:

H1 – H4 : JTMD species that have transported via vector X (i.e., hull fouling,

ballast water, aquaculture, and natural rafting/secondary spread) possess a

significantly different suite of distributional, environmental, and life history

traits than the JTMD species without prior (hull fouling, ballast water,

aquaculture, and natural rafting/secondary spread) history

2.3 Results

Species synthesis

The 105 JTMD species represent 12 phyla with Mollusca, Crustacea, Bryozoa, and Cnidaria accounting for 79% of the species included in this analysis (Figure 4).

Four phyla (Chordata, Cercozoa, Foraminifera, and Sipuncula) were each represented by one species. The reported native realm for the 105 JTMD species covers the globe with species ranging from the Southern Ocean to the Arctic.

However, the majority (> 70%) are native to the temperate Northwest Pacific and the Central Indo-Pacific. The majority of species had no invasion history (n = 69), while nearly a third had a known invasion history (n = 32), and a few were cryptogenic, meaning their origin is unknown (n = 4). Eight transport categories were documented, and the greatest number of species (32) were reported as hull fouling, followed by transport through aquaculture and fisheries trade and ballast water

(Figure 5). A total of 45 species out of 105 total have been documented on a vector.

In detail, that includes 30 species that have a known invasion history, 3 cryptogenic species, and 12 that were transported on a vector but have not clearly established

outside of their native region. There are three species classified as “Other”;

Dendostrea folium and Sphaerozius nitidus have both spread through the Suez Canal

as a means of transport. The third, Amblyosyllis speciosa, was classified as “Other”

by the EPA Atlas of Nonindigenous Marine and Estuarine Species (Lee II & Reusser,

2012). Fifty percent of the species are suspension feeders, while the rest are

omnivores, predators, herbivores, and deposit feeders (Figure 6). Almost all species

are reported with one trophic stage, however there are a few exceptions. The

polychaete Pygospio californica is reported as a deposit feeder and suspension

feeder, and all five shipworms are classified under herbivore as well as suspension

feeding.

30 29 28 25

20 16 15

10 10 8 5 5 3 Percent of (%) species Percent 2 1 1 1 1 0

Bryozoa Cnidaria Annelida Mollusca Crustacea Nemertea Cercozoa Chordata Sipuncula Arthropoda Foraminifera Echinodermata

Figure 4. The percent of Japanese Tsunami Marine Debris species per phyla (n = 105 species). The number of species per phyla is given above each bar.

Other 3 Moveable structures 4 Solid ballast 4 Recreation 6 Natural rafting/spread 18 Ballast water 21 Aquaculture 24 Hull fouling 32

0 10 20 30 40 No. of species documented per vector category

Figure 5. The number of JTMD species documented per transport vector; each species can be documented under multiple vectors. Forty-five species out of 105 total have been documented on a vector.

Deposit feeder Herbivore Predator Omnivore Suspension feeder

0 10 20 30 40 50 60 No. of species

Figure 6. The reported trophic level of 103 (out of 105) JTMD species.

Quantitative Analysis

Geographic distribution and prior transport

The variability in geographic distribution among the 97 species with and without prior anthropogenic transport, which excludes the eight species with deficient data for quantitative analysis, was well-described with a three-dimensional

NMS ordination. The ordination accounted for 88.1% of the variation in species' geographic distributions (stress = 11.5, 57 iterations). Axis 1 accounted for 54.1% of the variation and Axis 2 accounted for 34.0% of the variation. Along Axis 1, species distributed within the Temperate Northern Atlantic (r = − 0.682, adjusted p < 0.002) and the Mediterranean Sea (r = − 0.605, adjusted p < 0.002) were separated from those within the Temperate Northern Pacific (r = 0.616, adjusted p < 0.002) (Table

2). Along Axis 2, species from the Northeast Pacific (r = − 0.599, adjusted p < 0.002) were separated from species distributed within the Central Indo-Pacific (r = 0.701, adjusted p < 0.002) (Table 2).

Table 2. Pearson correlations with ordination axes: correlations between axis scores and the JTMD species’ geographic distribution from the NMS. These correlations are primarily for descriptive purposes. The correlation coefficient provides a way to compare the positioning of the JTMD species on ordination axes with the geographic variables (McCune & Grace, 2002). Only correlations that were significant after applying Bonferroni correction for multiple comparisons were included (a/m ; 0.05/32 = 0.002 ; this corresponds to r > 0.536).

Axis 1 Axis 2 Native Realm/Region r-value Native Realm/Region r-value Temperate Northern Pacific 0.616 Central Indo-Pacific 0.701 Ponto-Caspian -0.542 Northeast Pacific -0.599 Northeast Atlantic -0.597 Mediterranean Sea -0.605 Temperate Northern Atlantic -0.682

Figure 7a. Ordination of 97 JTMD species based on their documented geographic distribution. Species with prior anthropogenic transport (black pluses) and species without prior anthropogenic transport (gray triangles) in geographic space.

Figure 7b. Ordination of 97 JTMD species based on their documented geographic distribution. Graphs of the four vector group comparisons. (A) species with prior Hull Fouling (HF) transport (black circles) and species without prior HF transport in geographic space. (B) species with prior Ballast Water (BW) transport (inverted triangles) and species without prior BW transport. (C) species with prior Aquaculture and Fisheries (AQ) transport (squares) and species without prior AQ transport. (D) species with prior natural Rafting/Secondary spread (R/S) (diamonds) and species without prior R/S spread.

However, there were no differences in the geographic distribution of species with and without prior anthropogenic transport (MRPP; A = -0.003, p = 0.67). There were also no differences in the distribution of species with and without each vector

35 history, for all four vector groups: Hull fouling (MRPP; A = -0.0007; p = 0.44). Ballast water (MRPP; A = -0.002; p = 0.56). Aquaculture and fisheries trade (MRPP; A = -

0.002; p = 0.51). Natural rafting/secondary spread (MRPP; A = 0.002; p = 0.297).

Thus, with no significant differences between groups, no ISA was performed on the geographical distribution matrix.

Environmental and life history traits and prior transport

An ordination of the 97 species with and without prior anthropogenic transport based on environmental and life history traits accounted for a high level of variation (75.7%) within the data matrix (stress = 17.2, 84 iterations). Axis 1 accounted for 28.6% of the variation and separated species based on mobility, reproductive mode, development mode, trophic status, developmental mode, habitat, ecosystem, substrate and temperature regimes (Table 3). Axis 2 accounted for 26% of the variation in the dataset and separated species primarily on mobility, salinity regime, substrate, ecosystem, and invasion history (Table 3). Axis 3 accounted for 21.1% of the total variation and separated species based on temperature tolerance, spawning, development mode, and reproductive mode

(Table 3).

Anthropogenic and non-anthropogenic transport comparison

There was a significant statistical separation between species groups with different transport histories based on environmental and life history traits.

Anthropogenic traveler species (n=36) had traits that were different than the non- anthropogenic travelers (n = 61), (MRPP, A = 0.0365 , P < 0.0001). Based on the ISA, species with and without anthropogenic transport history were differentiated by substrate, ecosystem, and invasion history (Table 4). The anthropogenic travelers had invasion history, were reported on artificial and hardpan substrates (P < 0.001), in fouling habitats, and associated with temperate reefs (P < 0.001) more often than those without anthropogenic transport.

Vector specific comparison

H1 : Hull fouling species (n = 32) had traits that were different than JTMD species with no prior hull fouling history (n = 65) (MRPP, A = 0.04, P < 0.0001). Based on the

ISA, species with and without hull fouling history were differentiated by substrate, ecosystem, and invasion history (Table A3). Species with prior hull fouling history were reported on artificial and hardpan substrates, in fouling habitats, and associated with temperate reefs (P < 0.001) more often than species with no hull fouling history.

H2 : Ballast water species (n = 21) had traits that were different than JTMD species with no prior ballast water transport history (n = 76) (MRPP, A = 0.025, P < 0.0001).

Based on the ISA, species with and without ballast water transport history were differentiated by substrate, salinity, and invasion history (Table A4). Species with ballast water transport history were reported on artificial substrates (P < 0.001),

37 have a history of invasion (P < 0.001), and can survive in polyhaline waters (P <

0.001) more often than species with no history of ballast water transport.

H3 : Aquaculture and fisheries species (n = 24) had traits that were different than

JTMD species with no aquaculture transport history (n = 73) (MRPP, A = 0.029, P <

0.0001). Based on the ISA, species with and without aquaculture transport history were differentiated by substrate, salinity, and invasion history (Table A5). Species with a history of aquaculture transport were reported on artificial substrates (P <

0.001), have a history of invasion, and can survive in polyhaline water (P < 0.001) more often than species with no history of aquaculture transport.

H4 : Natural rafting/secondary spread species (n = 17) had traits that were different than JTMD species with no natural rafting/secondary spread history (n = 80) (MRPP,

A = 0.006, P = 0.054). Based on the ISA, species with and without natural rafting/secondary spread transport history were differentiated by habitat, ecosystem, salinity and temperature regime (Table A6). Species with natural rafting/secondary spread history were reported in pelagic habitats, in the water column, in floating plants and macroalgae, and can survive in cold water temperatures, and hypersaline water (P < 0.01) more often than species with no history of natural rafting/secondary spread.

Table 3. Pearson correlations with ordination axes: correlations between axis scores and the JTMD species’ traits from the NMS. These correlations are primarily for descriptive purposes. The correlation coefficient provides a way to compare the positioning of the JTMD species on ordination axes with the trait variables (McCune & Grace, 2002). Only correlations that were significant after applying Bonferroni correction for multiple comparisons were included (a/m ; 0.05/75 = 0.0007 ; this corresponds to r > 0.368)

Axis 1 Axis 2 Axis 3 Traits r-value Traits r-value Traits r-value Suspension feeding 0.669 Parthenogenesis 0.304 Lecithotrophic 0.500 Tropical 0.555 Mobility (less → 0.271 Budding 0.456 temperature regime more mobile) Subtropical 0.501 Oligohaline (0.5 to -0.403 Spermcast 0.433 temperature regime < 5) salinity regime Reproduction 0.434 Flotsam -0.424 Mobility (less → -0.394 (gonochoristic → ecosystem more mobile) hermaphrodite) Mangrove 0.383 Invasion history -0.463 Tropical -0.536 ecosystems (none → invader) temperature regime Muddy substrate -0.370 Temperate reef -0.468 Subtropical -0.647 ecosystem temperature regime Kelp forest -0.386 Mesohaline (5 to -0.547 ecosystems < 18) salinity regime Macroalgal bed -0.409 Fouling ecosystem -0.560 ecosystems Rocky intertidal & -0.418 Artificial substrate -0.611 subtidal ecosystems Tide flats -0.427 Polyhaline (18 to -0.612 ecosystems < 30) salinity regime Benthic larva -0.432 Biogenic substrate -0.634

Cold water -0.462 temperature regime Omnivore -0.483

Cool temperate -0.625 temperature regime Actively mobile -0.732 adult

Figure 8a. Ordination of 97 JTMD species based on environmental and life history traits. (A) anthropogenic traveler (AT) species ( ) and non-anthropogenic traveler species ( ) in trait space; Axis 1 (with 28.6% variation) versus Axis 2 (with 26% variation). (B) Axis 2 (with 26% variation) versus Axis 3 (with 21.1% variation) of the AT species and non-AT species in trait space.

Figure 8b. Ordination of 97 JTMD species based on environmental and life history traits. (A, B) species with prior Hull Fouling (HF) transport ( ) and species without prior HF transport ( ) in trait space. (A) Axis 1 versus Axis 2. (B) Axis 2 versus Axis 3. ( C, D) species with prior Ballast Water (BW) transport ( ) and species without prior BW transport ( ) in trait space. (C): Axis 1 versus Axis 2. (D) Axis 2 versus Axis 3. (E, F) species with prior Aquaculture and Fisheries (AQ) transport ( ) and species without prior AQ transport ( ) in trait space. (G, H) species with prior Natural

Rafting/Secondary (R/S) spread ( ) and species without prior R/S spread ( ) in trait space. (G) Axis 1 versus Axis 2. (H) Axis 2 versus Axis 3.

Table 4. Anthropogenic traveler traits. Traits with respective Indicator Values and p- values that were identified in the Indicator Species Analysis for species with prior anthropogenic transport and species without prior anthropogenic transport. All of the traits below were positively associated with the anthropogenic travelers, except for the last trait, ‘benthic larva’, which is positively associated with the non- anthropogenic transport species.

Trait Indicator Randomized p-value Value Indicator Value Invasion history 69.7 52.3 0.0002 Temperate reef ecosystems 54.9 31.3 0.0002 Fouling ecosystems 57.2 36.1 0.0002 Artificial substrate 62.8 36.7 0.0002 Hardpan substrate 19.4 6.3 0.0008 Hypersaline salinities 19.4 8.3 0.0050 Suspension feeding 44.2 32.1 0.0090 Supralittoral depth regime 15.2 6.4 0.0096 Polyhaline salinities 51.7 40.7 0.0106 Cold water temperatures 30.0 19.2 0.0182 Mesohaline salinities 33.9 23.5 0.0230 Rocky intertidal/subtidal ecosystems 50.3 44.1 0.0398 Benthic larva* 15.6 9.5 0.0484 *Only trait positively associated with the non-anthropogenic transport species group

Table 5. Traits that were positively associated with the four vector groups from Indicator Species Analysis tests. = p ≤ 0.001, = 0.001 < p ≤ 0.01, and = 0.01 < p ≤ 0.05.

Natural Hull Ballast Aqua- rafting/

Fouling Water culture Secondary TRAIT Species Species Species Spread Species

HABITAT Pelagic

Floating plants or macroalgae

Water column

ECOSYSTEM Flotsam

Temperate reef

Fouling

INVASION Prior invasion history

Mesohaline salinities

SALINITY Polyhaline salinities REGIME

Hypersaline salinities

Cold water temperatures

TEMPERATURE Cool temperate REGIME temperatures Warm temperate temperatures

Hardpan substrates

SUBSTRATE Artificial substrates

2.4 Discussion

The Great East Japan Earthquake and subsequent tsunami provided the novel opportunity to study the community of species that rafted on JTMD and allowed for a greater understanding of the transoceanic dispersal of marine species.

We examined the species that traveled on tsunami debris and their prior transport history to characterize the distributional, environmental and life history features associated with specific transport vectors to increase understanding of species transport pathways. The research questions were addressed through several specific comparisons. The first comparison was between 1) species that have prior, reported travel on rapid, anthropogenic vectors and 2) species that have no prior history of transport via anthropogenic vectors. The second part was four vector-specific species comparisons: The first three (hull fouling, ballast water, and aquaculture) are anthropogenic vectors that deliver organisms rapidly. The last comparison (natural rafting/secondary spread) includes processes that deliver species slowly via rafts and currents.

The primary aim of the study was to characterize the traits of anthropogenic travelers in comparison to the non-anthropogenic travelers, or species with no prior human-mediated transport, to identify traits that may make species more amenable to transport on anthropogenic vectors. A more detailed comparison of species traits was then completed among the four, most commonly reported prior vectors, ballast water, hull fouling, aquaculture, and natural rafting/secondary spread, to

44 characterize traits that may make species more amenable to transport on specific vectors.

The assortment of traits we found to be associated with the anthropogenic transport species are well suited to help species travel on hulls of ships, in ballast tanks of ships, and on the cargo of ships. We found that the anthropogenic travelers had prior invasion history, settle on hard and artificial substrates and occur in temperate reef ecosystems (composed of hard substrates such as oyster and mussel reef, worm reef, and coralline algae) more often than the non-anthropogenic travelers. They are also found in fouling ecosystems, such as boat hulls that support a community of organisms and are also characterized by suspension feeding. One trait that stood out for the anthropogenic travelers and can aid a species in their ability to transport to new regions is a preference for hardpan substrate. Specifically, out of all species in the database, only anthropogenic travelers are found on hardpan substrate, showing potential importance of that trait. Also, the anthropogenic travelers ability to attach and grow on artificial substrate is a good indicator of an effective traveling species. For example, introduced macroalgal species in Europe had a higher probability of being transported than the native species, based on the fact that they can grow on artificial substrate (including ships’ hulls) while natives seldom do (Nyberg & Wallentinus, 2005).

While the anthropogenic travelers were characterized by many traits, the non-anthropogenic travelers were only characterized by one trait (i.e. occurrence of benthic larvae). This difference may be, at least in part, because the anthropogenic

45 travelers are potentially a more cohesive species group with more similar life history traits than the non-anthropogenic travelers. Most of the non-anthropogenic travelers (56 out of 61) have no records of dispersal prior to rafting on JTMD. Thus, this group is potentially a more diverse conglomerate of species with an assortment of life history traits that JTMD was able to transport because it was a uniquely powerful dispersal event.

The anthropogenic traveler group included three vector groups, the hull fouling species, ballast water species, and aquaculture species. To better understand what makes an effective hull fouling, ballast water, or aquaculture traveler, these groups were analyzed separately in reference to species without that vector history.

According to our analyses, species with prior hull fouling history have prior invasion history and frequent temperate reef ecosystems. They are found in fouling ecosystems and on hardpan and artificial substrates more often than the species without prior hull fouling transport (Table 5). Traits that may facilitate successful transport include high tolerances to environmental stressors such as a large range of salinity and temperature. Accordingly, we found that the hull foulers have a wide range of salinity tolerance (mesohaline to hypersaline, 5 to > 40), and can survive in cold water more often than the species without prior hull fouling transport (Table 5).

Among the single vector groups (HF, BW, AQ, R/S) the hull fouling group was the largest with 32 species, which highlights the large relative contribution of the hull fouling vector to the JTMD species pool. According to a global study of introduced and cryptogenic species, more species have life history characteristics associated

46 with hull fouling (55 per cent) than any other vector (Hewitt and Campbell 2010), which is also represented in the JTMD species pool.

We found ballast water species to have similar traits as the hull fouling species. This finding was not surprising given that 20 of the 21 ballast water species are also hull fouling species. In addition, ballast water species more commonly occur in lower salinities (polyhaline and mesohaline) and in areas with warm temperate, subtropical, and tropical water than the species without prior ballast water transport.

We also found the traits that separated aquaculture and non-aquaculture species were similar to the traits that separated the hull fouling and non-hull fouling species. For instance, aquaculture species also have a wide range of salinity tolerance (mesohaline to hypersaline, 5 to > 40). This finding is influenced by the large species overlap between vector groups, where 21 of the 24 aquaculture species are also hull fouling species. However, species with prior aquaculture transport were also in flotsam, kelp forests, and occur in cold and cool temperate waters more often than the species without prior aquaculture transport.

We found that species with prior reported natural rafting and secondary spread are more commonly found in the water column, in pelagic habitats, in floating plants or macroalgae, and in cold, salty (hypersaline) waters than species with no prior reported natural rafting and secondary spread. We expect that species already in a pelagic marine environment, on floating plants would have a greater likelihood of transporting to new environments through natural currents. Secondary

47 spread after initial introduction can contribute to the success of invasive species

(Molnar et al. 2008), and is thus an important mechanism to understand. The dispersal distance by marine species through secondary spread and natural rafting is positively associated with wind and current speed (Thiel & Haye 2006, Gagnon et al.

2015). It has also been suggested that buoyancy can affect dispersal distance for secondary spread: buoyant fragments of the seaweed Codium fragile dispersed one to two orders of magnitude further than non-buoyant fragments (Gagnon et al

2015).

The ability to colonize on artificial substrates and live in fouling ecosystems has obvious implications for the transport potential of those species. Further, those traits have implications for invasion potential as well. An earlier study that examined the environmental and life history traits of the JTMD species with and without invasion history (Miller et al. 2018) also found species with known invasion history were reported on artificial and hardpan substrates, occurred in fouling habitats, temperate reefs, subtropical and tropical temperatures, and exhibited wider salinity tolerance more often than species with no prior invasion history. Most of the traits associated with the JTMD species with prior invasion history also characterized the species with prior transport, with the exception of the association to subtropical and tropical temperatures.

The development of the database on environmental and life history traits was limited by the information available in the literature on the JTMD species. Thus, some reproductive traits that have been associated with invasive species, such as

48 high fecundity (large brood size), elevated reproductive rate (large numbers of generations per year), and long longevity (Grabowski et al. 2007) were not available for most JTMD species. Additionally, it is possible that some species have wider salinity, temperature, or ecological tolerances than those reported. Some species may also have a more diverse transport history than reported. However, to the best of our knowledge, the available information for each species is included in the database.

Most of the JTMD species (70%) studied here with prior transport are polyvectic, meaning they have been transported on multiple vectors. Very few species are reported to occur only on a single vector (only 12 of the 41 JTMD species with prior transport). Polyvectism is a significant management issue – as soon as one vector is better understood and managed, another transport mechanism becomes available. For example, the polyvectic European shore crab (Carcinus maenas), native to western Europe, was transported globally through an increasing number of vectors, as more became available to it (Carlton & Ruiz, 2005). Carcinus’s dispersal history began in 1800, when only two methods of transport existed: solid ballast and hull fouling. By 2000, the number of dispersal vectors had more than tripled, and

Carcinus could disperse through ballast water, the movement of commercial oysters, lobsters, fish bait, in the aquarium trade, and has since been transported to North

America, South Africa, and Japan (Carlton & Ruiz, 2005). Five JTMD species have been reported on all four vectors of interest in this study (HF, BW, AQ, R/S), including the seastar Asterias amurensis, the amphipod Caprella mutica, the tunicate

Didemnum vexillum, the shore crab Hemigrapsus sanguineus, and the mussel

Mytilus galloprovincialis. All five species have known invasion histories, and two of these species, A. amurensis and M. galloprovincialis, are on the list of ‘100 of the world’s worst invasive alien species’ (Global Invasive Species Database, 2018). All of these species are experienced travelers, with traits that allow them to be successful at transporting on various mechanisms. Another concern is the JTMD species with invasion history. Of the 41 JTMD species with a prior reported transport history, 28 species have a known invasion history with clear establishment outside of their native range, 3 species are cryptogenic, meaning their origin is unknown and thus establishment outside of a native range cannot be determined, and finally 11 species were transported on a vector but have not clearly established outside of their native region. There could be management implications if any of these polyvectic, invasive species become established in novel regions after arriving on JTMD, with the potential for secondary spread and range expansion from the initial point of introduction via other vectors.

In this study, we cannot make conclusive claims about the life history patterns of each vector-specific group (HF, BW, AQ, R/S) due to the polyvectic nature of the species. In order to get a more definitive profile of a hull fouler, for example, next steps for future research would be to create and analyze a database of a larger subset of species, ideally with only prior hull fouling transport. If that is not possible due to the polyvectic nature of many traveling species, it may add value to the trait analysis if the species vector groups were split apart with more narrow

50 distinctions. For example, a focus on commercial hull fouling vs. recreational hull fouling may add value to the trait analysis. Similarly, in order to obtain a clear life history profile of ballast water, or aquaculture species, it may be necessary to analyze species more unique to the vector.

The effort to synthesize information on JTMD species contributes to our understanding of marine debris as a transport vector, and increases our ability to evaluate the vector. The species synthesis revealed that twelve different phyla came over, indicating that marine debris is able to transport a diverse assemblage of species. Many of the JTMD species are suspension feeders, and are well-adapted to the limited food resources on artificial floating substrata, which explains how many species were able to survive the long journey across the Pacific Ocean. In this work we identified traits that separated Japanese tsunami debris species with and without prior anthropogenic transport, and found the anthropogenic species have the ability to colonize on artificial substrates and live in fouling ecosystems, which has obvious implications for the transport potential of these species. Also, they have a high tolerance to environmental stressors such as a range of salinity, which can facilitate successful species transport. The results from this study can offer a suite of traits that may increase the tendency for coastal invertebrates to travel on human- mediated transport vectors, and can thus increase our scientific understanding of species dispersal.

Historically, as ships have become faster, the vector duration has decreased

–and a shorter voyage duration may lead to increased survival of the propagules

(Carlton & Ruiz, 2005). However, in the case of JTMD, it is unclear whether the long vector duration significantly impacted survival. Western Pacific coastal species survived for nearly 6 years drifting to the Eastern Pacific. JTMD was able to transport hundreds of living species to North American coastlines, with some in good reproductive condition. The amount of plastics and anthropogenic marine debris available in the ocean is increasing (Eriksen et al. 2014, Barnes 2009, Jambeck

2015), which can in turn increase the frequency of species rafting on anthropogenic marine debris (Barnes 2002, Carlton et al. 2017). Due to increasing shoreline infrastructure and development (Neumann et al. 2015), there are more sources of nonbiodegradable materials available for marine organisms to colonize. Climate change is simultaneously associated with increasingly severe storms that are more efficient at ejecting debris into the ocean (Baldini et al. 2016, Sobel et al. 2016). An increase in the vector frequency could, in turn, increase the propagule pressure and the strength of the marine debris vector (defined as the number of established invasions that result from a given vector within a specified time period and location)

(Carlton and Ruiz, 2005). These changes could cause an increase in ocean rafting which may result in an increased frequency of species invasions (Carlton et al. 2017).

For example, in New Zealand, the rafting of non-native marine species on anthropogenic marine debris (specifically plastic rope released from aquaculture activities) was deemed by Campbell et al. (2017) an unmanaged threat to biosecurity. To address the currently unmanaged threat of marine debris transporting non-native species, Rech et al. (2016) identified key knowledge gaps

52 surrounding the issue, and suggest the urgent need for more research in order to inform management actions and preventative measures. It has been suggested by

Rech et al. (2018) that the composition of anthropogenic litter can be used as a management tool to predict the attached biotic community, including invasive species. Some studies call for a reduction in the amount of plastic pollution and other anthropogenic marine debris that is released into the marine environment, to limit the chance of biofouling and species transport in the first place (Campbell et al.

2017; Goldstein et al. 2014). This may be the most effective way to manage the issue and to limit the impacts that debris-associated rafting communities can have on coastal ecosystems.

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Chapter 3 Marine Debris In Oregon: A Survey of Research Priorities

3.1 Introduction

The disposal of plastics and other persistent solid materials (debris) into the oceans and seas is a global issue of growing concern. Marine debris consists of a wide variety of refuse ranging from soda cans, plastic bottles, buckets, packaging materials, polystyrene foam, bags/film to derelict fishing gear (nets, lines, buoys, traps) and abandoned vessels (Eriksen et al. 2014). Plastic pollution has reached a global scale to where it is present in almost every environment and every location of the world (Barnes 2009, Galgani 2015). The ocean is particularly vulnerable as it receives both land-based (from rivers, sewers and storm drains) and ocean-based

(fishing activities and shoreline recreational activities) litter (Lebreton et al. 2017,

Galgani et al. 2015, Araujo & Costa 2007, Rech et al. 2014). However, most marine debris (about 80%) originates on land (Derraik 2002).

The quantities of marine debris appear to be constantly increasing as are the problems related to marine debris (Barnes et al. 2009, Ryan et al. 2009). It has recently been estimated that the ocean contains over 5 trillion floating plastic pieces weighing over 250,000 tons (Eriksen et al. 2014). These materials cause many negative impacts on marine environments (Derraik 2002, Gregory 2009). Plastic pollution causes the death of marine animals through entanglement and ingestion, toxic human health concerns, navigation hazards, transport of non-native species, and severe damages to ecosystem services like tourism, fishing, and other recreational activities at beaches and natural areas (Gregory 2009, Newman et al.

2015, Gall & Thompson 2015, Galloway 2015, Thiel & Gutow 2005, Kiessling et al.

2015).

Plastics over time break down and fragment to smaller and smaller pieces, forming microplastics (Barnes et al. 2009). Microplastics are plastic marine debris less than 5 mm in size (Law & Thompson, 2014) and are estimated to make up more than 90% of the plastic particles in the global ocean by count (Eriksen et al., 2014).

Eriksen et al. (2014) have observed a loss of microplastics from the sea surface compared to expected rates of fragmentation, suggesting there are mechanisms involved that remove the small plastic particles from the ocean surface.

The issue of microplastics is a growing concern, and understanding its sources and impacts will be critical in addressing the issue. Microplastics are washed to the ocean through multiple sources. This can occur when personal care products such as face wash or toothpaste containing microbeads are rinsed down a drain, or clothes containing synthetic fibers are washed. Microplastics bypass water treatment plants because of their small size (Fendall & Sewell, 2009). Potential impacts include the accumulation of toxins on the surface of microplastics (Mato et al., 2001) and organisms’ ingestion of plastics. Microbes were shown colonizing the surface of microplastics, potentially being transported to new ocean areas or sinking the plastic from the surface (Zettler et al. 2013). Many species of fish, bivalves, and sea birds (Rochman et al. 2015, Gregory 2009) even deep-sea organisms (Taylor et al. 2016) have been reported to eat microplastics. The impacts of microplastics after consumption by many of these animals are still unclear.

In recent decades, there have been campaigns against the production and consumption of single-use plastics, for example banning plastic bags from supermarkets, and taking plastic microbeads out of personal care products, (e.g. http://storyofstuff.org/, http://www.beatthemicrobead.org/). Public awareness and increasing evidence of the issues from plastic pollution has resulted in requests for policy changes, and some changes have been implemented, such as the recent ban of microbeads in personal care products in the United States, Canada and the U.K., with more countries to follow (Clapp & Swanston 2009, Doughty & Eriksen 2015).

Research on this topic is ongoing, and many of the impacts of debris in the ocean are unknown. There is a need for more marine debris research, in order to understand the potential and realized impacts and to encourage the prevention and reduction of marine pollution. Efforts in Oregon from the marine debris community are ongoing to address the need for more marine debris research.

Oregon Marine Debris Research Prioritization Workshop

In 2016 in Oregon, local stakeholders convened to develop research actions to help combat marine litter, in the Oregon Marine Debris Action Plan (OR MDAP).

One of the actions identified was to “develop research priorities for marine debris in

Oregon with a focus on sources and reduction strategies; encourage research to quantify and prevent the impacts of marine debris” (Oregon Marine Debris Action

Plan 2017). The National Oceanic and Atmospheric Administration Marine Debris

Program (NOAA MDP) and Oregon Sea Grant partnered with Oregon State University

(OSU) and the Environmental Protection Agency to engage local stakeholders in a workshop to prioritize research on the marine pollution problem in Oregon. A pre- workshop survey including a list of research topics, which was generated by local stakeholders for the OR MDAP, was sent to Oregon practitioners before the workshop to be reviewed, ranked, and expanded.

The pre-workshop survey was designed and sent out by NOAA Marine Debris

Program’s Matthew Coomer and Nir Barnea to 67 practitioners from Oregon in industry, academia, non-government organizations, and federal, state, and tribal government. The survey included 16 marine debris research topics. Those marine debris (MD) research topics were measured on a 3-point scale from one (low priority) to three (high priority) by respondents (See Table 6 for the complete list).

The survey also asked for participant suggestions on additional MD research topics.

The pre-workshop survey generated five additional MD research topics that were proposed by respondents, and added to the final list of priorities (#17 – 21). Based on the replies of this pre-workshop survey, the organizers then prepared a marine debris research priorities list, and participants attended a one-day workshop at OSU in Corvallis, Oregon to evaluate and prioritize these research ideas.

On May 30, 2017, twenty-four marine debris researchers and practitioners attended the Oregon Marine Debris Research Priorities Workshop. The workshop built upon the OR MDAP, with a goal of prioritizing research topics to help address local marine debris issues. Participants examined and ranked research needs in order to establish top research priorities. These rankings reflect the participants’

62 views of current research needed to best support Oregon efforts to address marine debris. (National Oceanic and Atmospheric Administration Marine Debris Program,

2017).

Following the workshop which engaged local researchers and managers, my goal was to take the same list of marine debris research priorities and expand the audience to a larger Oregon population. By expanding the NOAA Marine Debris

Program survey audience to interested citizens (people with any interest in marine issues), citizen scientists (volunteers/people engaged with marine issues), researchers (scientists), and managers, I can gain a larger perspective and identify varying priorities among groups, if any, in order to prioritize future prevention efforts. The survey was distributed in order to answer four questions:

1. How can we help focus marine debris research efforts in Oregon even though extensive knowledge gaps exist? 2. Which marine debris research topics are high priority for Oregon stakeholders? 3. What differences exist in priorities for marine debris research among interested citizens, researchers, citizen scientists, and managers? 4. Is conducting research on marine debris as a vector for non-native species a high priority for Oregon stakeholders?

With limited available funding for marine debris research in Oregon and the need to bridge knowledge gaps, the prioritization and ranking of marine litter research topics can help to improve research efficacy and applicability. The results of the expanded survey will be sent to NOAA Marine Debris Program for further use.

3.2 Methods

I utilized a multi-method approach to gather data to address the research questions. This section describes the expanded survey questionnaire, participant recruitment, and the sampling approach.

Expanding the NOAA MDP Survey Questionnaire

In order to capture a wider Oregon audience, I sent the list of 16 research topics from the pre-workshop survey to the Marine Resource Management program at Oregon State University through a mailing list. The final list of 21 priorities (16 original, and 5 from the pre-workshop suggestions) was then compiled and further distributed to increase the number and type of respondents. In contrast to the pre- workshop survey, data were collected in person and online, after Oregon State

University’s Institutional Review Board determined this project did not meet the definition of human-subjects research under the regulations set forth by the

Department of Health and Human Services 45 CFR 46 (Study ID 8078). Online participants were contacted through circulation on two more mailing lists: 1) Oregon

Sea Grant volunteers and 2) the Hatfield Marine Science Center mailing list. Hard copy surveys were collected at the Visitor Center at Hatfield Marine Science Center in Newport, Oregon. Data collection took place between June 22nd, 2017 and

September 11th, 2017. The online and onsite questionnaires were identical, and requested the following types of data: self-reported placement into one of five groups (manager, researcher, citizen scientist, interested citizen, or other (fill in

64 response)) and marine debris priority rankings. The complete questionnaire is in

Appendix B.

MD research topics were measured on a 3-point scale from one (low priority) to three (high priority), where respondents were prompted to rank each of the 21

MD topics (See Table 6 for the complete list). The survey also allowed a “don’t know” response for all 21 of the marine debris topics.

In this analysis, mean scores were used for calculating the priority rank of each of the 21 MD research topics. The mean priority scores of each MD topic were also separated by group (manager, researcher, citizen scientist, interested citizen, and other).

Table 6. The 21 marine debris research topics present in the questionnaire.

Quantitative assessment of marine debris deposition/accumulation along 1 Oregon coast. 2 Marine debris impact on Oregon’s economy. 3 Marine debris impact on Oregon’s ecosystems. 4 Sources, quantity, and types of marine debris in Oregon. 5 Sources, quantity, and types of microplastics. Microplastics deposition along the Oregon coast: baseline and seasonal 6 variability. 7 Microplastics impact on Oregon’s ecosystems. 8 Assessment of marine debris as a vector for non-native species. 9 Evaluation of invasive species colonization on Japanese Tsunami Marine Debris. Methods to capture synthetic clothing fibers before depositing in the marine 10 environment. 11 Determine the annual average loss of crab pots in Oregon 12 Evaluate methods to improve data collection during cleanups. Evaluate efficacy of beach cleanups: areas cleaned, optimal frequency of 13 cleanups.

Develop and evaluate a matrix to prioritize marine debris cleanup in Oregon 14 based on debris accumulation and area sensitivity. 15 Determine the overall cost associated with marine debris cleanup in Oregon. Evaluate marine debris prevention efficacy: education and outreach, legislation 16 and regulation, upstream capture devices. Investigate best approaches for working with industry to reduce plastic waste, 17 especially packaging. Baseline survey of marine debris knowledge in Oregon: general plastic pollution 18 knowledge, plastic consumption and use habits. 19 Determine the source of trawl nets that come ashore on Oregon beaches. Literature search on major marine debris research to better focus local research 20 on knowledge gaps. Life cycle assessment of popular plastic alternatives – what are their 21 environmental impacts?

Participants

Those that responded to the survey had some level of interest in marine debris issues in Oregon – otherwise they would not have voluntarily spent time to provide a response. Because no demographic information was collected, it was not necessary for participants to live on the coast, or even to reside in Oregon.

Sampling Approach

Due to the broad scope of the target population, a full list of the population of people with an interest in Oregon’s marine debris issues was not available. To increase the number of respondents, a multistage sampling method was used

(Vaske, 2008). The first stage employed a convenience sample of online participants contacted through Oregon Sea Grant, the Marine Resource Management program at

Oregon State University, and Hatfield Marine Science Center. The second stage used

66 a convenience sample of on-site participants at the Visitor Center at Hatfield Marine

Science Center. A convenience sample is a subgroup of the population to which the researcher has ready access, and is used when a complete list of the population is not available (Vaske, 2008).

Oregon Sea Grant is an ocean science and outreach government program that supports coastal communities through research, extension and education. The

Marine Resource Management program is a graduate program at Oregon State

University that fosters cooperative discovery and learning about the conservation and use of marine resources. Hatfield Marine Science Center is a marine laboratory in Newport, Oregon. Hatfield hosts collaborative research and education programs from seven Oregon State University colleges and six state and federal agencies. The

Visitor Center at Hatfield is managed by Oregon Sea Grant, and has marine science exhibits that are free and open to the public. The Visitor Center has a touch tank of marine organisms, an octopus, fish, interactive games, and many other exhibits that promote marine education to the public.

Online and on-site survey recruitment materials were kept short in accordance with recommendations by Vaske (2008), with three sentences of text as introduction (Appendix B). The online survey was built and distributed through

Qualtrics survey software system, licensed through Oregon State University.

The questionnaire was distributed on June 22nd, 2017 to the 30 members of the Marine Resource Management mailing list. 6 responses were received that same day, and 8 more after one week. The survey link was also posted in a newsletter sent

67 to the 80 members of the Oregon Sea Grant volunteer mailing list on July 7th, 2017.

Five responses were received that day, and 3 more were received over the next 3 days. On July 27th, 2017, the survey link was circulated through the Hatfield Marine

Science Center community mailing list which has 720 members. 12 surveys were completed that day and 26 were received the next day. Over the next two weeks, 21 more individuals completed the questionnaire. Overall, 81 surveys were completed online.

On July 22nd, 2017, visitors to the Hatfield Marine Science Center Visitor

Center were surveyed in person by R. Gillman. Between 11 AM to 2 PM, 19 hard copy surveys were completed by visitors. The on-site sampling was done over the summer on a Saturday to maximize the number of respondents, as the summer weekends attract more visitors to the Oregon coast and the Visitor Center. On the day of on-site sampling a total of 1,045 people visited the Visitor Center. All visitors that came near the touch tank of marine organisms near the front were approached and asked if they would be willing to fill out a survey on marine debris. If there was a group, all members of the group were asked to fill out a separate survey to avoid social bias. Verbal consent was obtained and the goals of the project were briefly explained, and the survey was handed out and collected. Completion of the survey usually required 5 – 10 minutes.

3.3 Results

Surveys were completed by 116 respondents; 16 pre-workshop, 81 online, and 19 onsite. The respondents included 19 managers, 42 researchers, 20 citizen scientists, 31 interested citizens, and 4 other (self-reported as “educator”, which became a fifth group, see Figure 9). Participants returned complete surveys, with only 1% of cells blank (23 out of 2,296 total cells) (see Figure 10).

Figure 9. Marine debris survey participants by group (Manager, Researcher, Citizen Scientist, Interested Citizen, and Educator). Group percentages are out of 116 total survey participants.

Figure 10. Total number of blank, unanswered questions for all respondents combined. Only 23 out of 2,296 total cells were skipped (which is 1% of cells).

Priorities for all Participants

Participants were asked to rank 21 marine debris research topics on a scale from

1 (low priority) to 3 (high priority). The three research topics with the highest priority average scores across all participants are:

1) Marine debris impact on Oregon’s ecosystems (x̄ = 2.89) (Topic 3)

2) Microplastics impact on Oregon’s ecosystems (x̄ = 2.84) (Topic 7)

3) Investigate best approaches for working with industry to reduce plastic

waste, especially packaging (x̄ = 2.78) (Topic 17)

The three marine debris topics with the lowest priority mean scores across all participants are:

1) Determine the annual average loss of crab pots in Oregon (x̄ = 2.03) (Topic

11)

2) Literature search on major marine debris research to better focus local

research on knowledge gaps (x̄ = 2.04) (Topic 20)

3) Determine the source of trawl nets that come ashore on Oregon beaches (x̄ =

2.06) (Topic 19) (See Figure 11)

3.50

3.00

2.50

2.00

1.50

1.00

0.50 AVERAGE PRIORITY RANKING SCORE RANKING PRIORITY AVERAGE 0.00 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 MARINE DEBRIS TOPIC NO.

Figure 11. Average (± SE) priority rank score by marine debris topic number for all participants. Topics 1–16 are based on 116 total survey responses, and topics 17–21 are based on 88 total survey responses.

Priorities across Groups

There are some differences in high and low priority issues among groups.

However, the top three research topics across all participants (see above) which are topic #3, #7, and #17 appear in the top five highest mean scores across all groups, and are thus important issues for all five groups.

Highest Priority Research Topics Among the Five Groups

Marine debris and microplastics impact on Oregon’s ecosystems and working with industry to reduce plastic waste, especially packaging (Topics 3, 7, and 17) received the highest mean scores among the researchers, citizen scientists, interested citizens, and educators (See Figure 12). The managers were in agreement with the other four groups and ranked marine debris and microplastics impact on

Oregon’s ecosystems (Topic 3 and 7) as the highest priority. However, the research topic of third highest importance for managers was sources, quantity, and types of microplastics (Topic 5) (x̄ = 2.76). The small educators group (n = 4) had five research topics tied for highest priority. In addition to topics 3, 7, and 17, the educators also ranked Topic 11 [determine the annual average loss of crab pots in Oregon (x̄ = 3.0)], and Topic 16 [evaluate marine debris prevention efficacy: education and outreach, legislation and regulation (x̄ = 3.0)] with the highest mean priority scores.

Lowest Priority Research Topics among the Five Groups

Managers, researchers, and citizen scientists all ranked (Topic 19) determine the source of trawl nets that come ashore on Oregon beaches as one of the three lowest priority research topics. Researchers, interested citizens, and educators were also in agreement and ranked (Topic 20) literature search on major marine debris research to better focus local research on knowledge gaps as one of the three lowest priority research topics.

basedon total 88 are are 21

– 17

Topics number,separated by the five

ic top

bymarine debris

ing scores ing

basedon 116 totalsurvey responses.

16 are are 16 – priorityrank

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cipantgroups. Topics 1

Figure parti responses. survey

The managers, however, had a few different low priority results compared to the other four groups. The two topics with the lowest mean scores among managers are both in regards to non-native species’ transport on marine debris. These are

(Topic 9) evaluation of invasive species colonization on Japanese Tsunami Marine

Debris (x̄ = 1.47), and (Topic 8) assessment of marine debris as a vector for non- native species (x̄ = 1.5). Another point of interest for the managers was the comparatively extreme range of high and low votes for this group. The difference between the manager’s highest mean score and the lowest mean score is the greatest out of all five groups (range = 1.53).

The topic with the lowest mean score among both educators and citizen scientists is (Topic 2) marine debris impact on Oregon’s economy (x̄ = 2.25, x̄ = 2.11).

The citizen scientist group also ranked the following research topic as low priority:

(Topic 15) determine the overall cost associated with marine debris cleanup in

Oregon (x̄ = 2.11). (See Figure 12). In addition, the citizen scientists, in contrast to the managers, had a very low range of high and low votes. The difference between the citizen scientist’s highest mean score and the lowest mean score is one of the lowest out of all five groups (range = 0.84). The topic with the lowest mean score among interested citizens is (Topic 11) determine the annual average loss of crab pots in Oregon (x̄ = 1.96).

6.9 2.3 21 31.0 59.8 8.0 20 23.9 40.9 27.3 19 21.6 40.9 27.3 10.2 1.1 18 10.2 39.8 48.9 2.3 17 17.0 80.7 based on total 116

list of the 21 marine marine 21 the of list 2.7 1.8 16 31.0 64.6 16 are 1.7 15 – 21.7 43.5 33.0 LowPriority 5.3 14 10.5 31.6 52.6 Topics 1

See Table 6 for a for 6 Table See

2.6 13 14.8 48.7 33.9 3.5 12 16.7 48.2 31.6 Medium Priority Medium 6.1 11 23.5 44.3 26.1 7.0 10 18.3 29.6 45.2 marine debris topic; percent of high, medium, and low high,of percent medium,and topic; debris marine High Priority MARINE DEBRIS TOPIC NO. 9 4.3 22.4 41.4 31.9 by 8 7.0 17.4 34.8 40.9 Don’t Know basedon 88 total survey responses. 7 0.9 0.9 14.7 83.6 are are 21 6 4.4 1.8 43.0 50.9 – 17

5 4.5 5.4 27.7 62.5 Topics 4 6.0 1.7 30.2 62.1

3 Total survey response composition 11.3 88.7

. 3 1 2 1.8 14.0 52.6 31.6 Figure priorityvotes per topic, as well percentas ‘don’t of know’ votes per topic. responses. survey debristopics. 1

9.6 0.9

36.5 53.0 RESPONSE PERCENT COMPOSITION PERCENT RESPONSE

Response Composition

Participants were asked to rank 21 marine debris research topics on a scale from 1 (low priority) to 3 (high priority), with an option for a ‘don’t know’ response when the respondent either did not understand the topic, or could not rank the topic as high, medium, or low (See Figure 13). For all participants across all topics, there is a total tally of 1,122 ‘high’ votes, 801 ‘medium’ votes, 272 ‘low’ votes, and

78 ‘don’t know’ votes. Overall, the amount of ‘high’ votes in the survey is more than

4x the amount of ‘low’ votes; showing the respondents were more generous with ranking a topic high priority (and medium priority), and less inclined to give a low priority ranking. The topics that respondents knew the least about, or chose ‘don’t know’ most frequently for were 19, 20, 8, and 10. The topics with the highest percent composition of low priority votes were 20, 11, and 9. The topics with the highest percentage of medium priority votes were 2, 12, and 13. Finally, the highest percentage of high priority votes were for topics 3, 7, and 17.

3.4 Discussion

The disposal of plastics and other materials into the oceans and seas is a global issue of growing concern. Plastic pollution causes the death of marine animals through entanglement and ingestion, human health concerns, navigation hazards, transport of non-native species, and severe damages to tourism, fishing, beaches and natural areas (Gregory 2009, Newman et al. 2015, Gall & Thompson 2015,

Galloway 2015, Thiel & Gutow 2005, Kiessling et al. 2015). Research on this topic is ongoing, yet many of the impacts of debris in the ocean are unknown. There is a need for more marine debris research, in order to understand the potential and realized impacts and to encourage the prevention and reduction of marine pollution.

The goal of this work is to prioritize and rank marine litter research topics that are relevant to Oregon, through a survey sent out to an expanded Oregon population base of interested citizens, citizen scientists, researchers, and managers. By increasing the survey audience, the goal is to gain a larger perspective and identify varying priorities among groups, if any, in order to prioritize future research efforts.

The results of the expanded survey will be sent to NOAA Marine Debris Program for further use.

Addressing Research Questions 1 and 2 How can we help focus marine debris research efforts in Oregon even though extensive knowledge gaps exist? And what marine debris research topics are high priority for Oregon stakeholders?

Despite extensive knowledge gaps in the sources, impacts, and solutions to marine debris in Oregon, it is possible to prioritize the research efforts. After surveying 116 participants, three marine debris research priorities emerged out of twenty-one total as highest priority for Oregon stakeholders surveyed. These were:

1) marine debris impact on Oregon’s ecosystems, 2) microplastics impact on

Oregon’s ecosystems, and 3) investigate best approaches for working with industry to reduce plastic waste, especially packaging. Building on the work done at the workshop and through the pre-workshop survey, by expanding the survey audience

77 to more Oregon stakeholders, I provide additional perspectives on marine debris research priorities in Oregon. With limited available funding and the need to bridge knowledge gaps, the prioritization and ranking of marine litter research topics can help to improve research efficacy and applicability. These three research areas are potential focal points for marine debris researchers and practitioners in future research efforts. Current scientific research is being conducted on microplastics and marine debris impacts on organisms and ecosystems (Rech 2018, Taylor 2016,

Zettler 2013, Rochman 2015), but more could be done with a focus on Oregon’s ecosystems to address the local need. The third highest priority item, which is working with industry to reduce plastic waste, is a highly complex issue that may be a challenge to address at the local level if addressing a global industry. However, industrial packaging waste prevention within Oregon could be addressed through many various measures, such as spreading prevention and reuse awareness to different industries as cost-effective and beneficial to the environment. Many

Oregon businesses may be able to save money – anywhere from thousands to millions of dollars a year – through changing their packaging (Oregon Department of

Environmental Quality 2018).

The top priority items from the survey address ecological consequences.

These results suggest participants have higher concern for ecological impacts and can help to prioritize future marine debris research efforts in Oregon.

Addressing Research Question 3: What differences exist in priorities for marine debris research among managers, researchers, citizen scientists, and interested citizens?

Overall research priorities were very similar across groups for both high and low priority items. Managers prioritized microplastics research with two of their top three priority research topics related to microplastics. Public awareness and increasing evidence of the issues from microplastics has resulted in requests for policy changes (Clapp & Swanston 2009, Doughty & Eriksen 2015), and some changes have been implemented, such as the recent federal ban on personal care products containing microbeads in the United States, which was passed in December

2015. The Microbead-Free Waters Act of 2015 phases out the sale and manufacture of personal care products with plastic microbeads by 2018. These national legislative actions will make a big difference in microplastic pollution, but still more research can be done at the local level, such as identifying risk hotspots for microplastics in

Oregon’s coastal waters to determine optimal removal locations (Sherman 2016).

Addressing Research Question 4: Is conducting research on marine debris as a vector for non-native species a high priority for Oregon stakeholders?

Research topics about marine debris as a vector for non-native species, and research on invasive species on Japanese tsunami marine debris were the lowest priority for the managers. Across all participants, these research topics were of lower priority as well. Non-native species floating on marine litter is one of the lesser-known impacts associated with marine debris (Rech et al. 2018). This issue, in contrast to images of plastic ingestion by marine animals and microplastics, attracts

79 less public and media attention. A lack of knowledge and exposure to this issue could contribute to its low priority of the twenty-one research topics contained in the survey. Alternatively, it may be lower priority because it is a complex issue and its impact on coastal ecosystems and marine biodiversity is not yet well known (Rech et al. 2016). These results suggest that research on marine debris as a vector for non-native species may not fully be addressed unless it becomes a larger, increasingly documented issue.

While the survey captured some of the Oregon population, there are limitations to the scope of this work. The survey contained survey bias based on the fact that the respondents were obtained through a convenience sample, and thus do not represent a random sample of the target population. Future survey efforts could continue to capture more of the Oregon population and, with a random sample, the results could be generalized to the population of Oregon. This survey work did not collect demographic information, which could be a point of interest for future work in determining varying priorities among demographic groups. Additionally, this survey answers the ‘what’ but not the ‘why’ of marine debris research priorities for

Oregon. In this work, we learned what marine debris research topics were the highest priority for Oregon, but not why. Potential further work could incorporate qualitative research of Oregon coastal residents to better understand what is important to them and why, in regards to marine debris in Oregon.

In order to inspire action or a change in behavior, it is important to understand why the behavior is occurring. While beyond the scope of our survey

80 efforts, future surveys on marine debris research could measure behavior in order to get at prevention, reduction, and solutions for the marine pollution problem. There is evidence that several factors can inspire changes in behavior, such as focusing on local issues, self-efficacy, and taking the values and beliefs of the audience into consideration (Chawla & Cushing 2007, Stern 2000). The belief that your own actions make a difference, or self-efficacy, can strengthen the prospect of action when there is also the belief that one has the capability and resources to be successful.

Prioritizing marine debris research areas relevant to Oregon is a step in the right direction towards sustainable solutions. Because there are large global differences in the causes of plastic pollution, both on land and at sea, solutions for marine pollution may be more effective if research efforts are context specific and if local conditions are taken into account (Jambeck et al. 2015, Chen et al. 2015).

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Zettler ER, Mincer TJ, Amaral-Zettler LA. Life in the “plastisphere”: microbial communities on plastic marine debris. Environmental science & technology. 2013. 47(13):7137-46.

Chapter 4: Conclusion

The global issue of marine debris, while complex, is being addressed one step at a time. With the prioritization of possible avenues of research for Oregon, the results of our marine debris survey can help to guide local marine debris research.

The results of the workshop and our expanded survey efforts can help focus the efforts of researchers, managers, policy makers, and everyone working to solve marine debris issues in the broader marine debris community.

Through the survey, we found that marine debris as a vector for non-native species is not a top priority among people we surveyed. This may partly be due to a lack of knowledge on the topic as some may have never heard of the phenomenon before. Despite the fact that it is a lower priority item compared to the other marine debris research topics present in the survey, it is still an important management question that should be addressed. However, because it is lower in comparison to other issues such as microplastics, the issue of marine debris as a vector for non- native species may not fully be addressed until it has become a larger, well- documented issue.

The JTMD megarafting event was unique and a powerful method of species dispersal. If the JTMD rafting event has taught us anything, it is a caution regarding what changes may come in the future. Historically, vector studies have been focused on fast-moving vectors, associated with commercial shipping, ballast water, and commercial aquaculture (Fofonoff et al. 2003, Grosholz et al 2015). Shipping and

85 aquaculture have been pointed to as the most critical global transport of marine invasive species (Molnar et al. 2008, Carlton & Geller 1993, Carlton 1985). We now have the slower-moving vector of marine debris that is becoming more important for species dispersal as we move into the future. We have enough evidence to know that these issues need to be addressed. The next steps forward involve management actions and preventative measures.

Current efforts to address the marine debris issue include scientific research to better assess sources, fate, abundance and impacts, legislative action such as the passage of the Microbead-Free Waters Act of 2015, and innovative technologies.

Education also plays an important role in reducing plastic in the ocean. Awareness of environmental issues like plastics in the ocean is associated with people feeling concern for their environment (Gelcich et al. 2014). Changing beliefs and feelings of self-efficacy around the issue (Stern 2000) as well as increasing awareness and accurate knowledge can potentially promote behaviors that lead to a reduction of plastics in the marine environment.

Solutions to the marine litter problem will be found as we as a society transition towards a more sustainable way of life. If our culture can transition away from single-use plastics, and the convenience of throw-away living, we can reduce our waste a great deal. By the year 2022, the Clean Seas global campaign on marine debris by United Nations Environment (UN Environment) has an aim to eliminate microplastics in cosmetics globally and the extremely wasteful utilization of single- use plastic. Innovative technologies are being developed, such as filters for washing

86 machines to stop synthetic fibers from reaching the oceans (e.g. http://guppyfriend.com/en/). Long-term sustainable solutions will involve much more than recycling and composting, but will need waste reduction, and a much improved system of production and consumption. On a more positive note, it is possible that the devastating marine litter problem will encourage a shift towards more sustainable lifestyles, and more sustainable economies (Veiga 2016). Hopefully we can continue to make the shift from short-term to long-term solutions.

“ We must understand and define conservation and social justice as our collective self-preservation–a rationale that crosses all boundaries between all people.”

– Marcus Eriksen, marine debris researcher and activist, in his book My River Home

References

Carlton JT. Transoceanic and interoceanic dispersal of coastal marine organisms: the biology of ballast water. Oceanography and Marine Biology; An Annual Review. 1985. 23:313-71.

Carlton JT, Geller JB. Ecological roulette: the global transport of nonindigenous marine organisms. Science. 1993. 261(5117):78-82.

Gelcich S, Buckley P, Pinnegar JK, Chilvers J, Lorenzoni I, Terry G, Guerrero M, Castilla JC, Valdebenito A, Duarte CM. Public awareness, concerns, and priorities about

anthropogenic impacts on marine environments. Proceedings of the National Academy of Sciences. 2014. 111(42):15042-7.

Grosholz ED, Crafton RE, Fontana RE, Pasari JR, Williams SL, Zabin CJ. Aquaculture as a vector for marine invasions in California. Biological Invasions. 2015. 17(5):1471-84.

Molnar JL, Gamboa RL, Revenga C, Spalding MD. Assessing the global threat of invasive species to marine biodiversity. Frontiers in Ecology and the Environment. 2008. 6(9):485-92.

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UN Environment. 2017. http://www.unep.org/news-and-stories/story/indonesia- joins-un-bid-eradicate-ocean-plastic. Retreived Aug 2018.

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