Barna Volume VI Spring 2019 BARNA Journal of Student Initiated Research

Volume IV Spring 2020 1

CIEE Perth

Photograph credits Front Cover: Alicia Sutton Title page: Alicia Sutton Biography Photos: Kate Rodger, Alicia Sutton, Faith Lundberg, Avery Zartarian, Jesse Girolamo Table of contents: Rick Stuart-Smith- Life Survey, providencetrade.com, Daniel Norwood Back Cover: Alicia Sutton

Editors Editor-in-Chief: Alicia Sutton Text Editor: Kate Rodger Format Editor: Alicia Sutton

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Barna Journal of Student Initiated Research

CIEE Perth Biology and Ecology Field Studies Volume IV Spring 2020

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FOREWORD

Students who participated in the Independent Field Research Project for Biology and Ecology Field Studies were given the opportunity to showcase their research in the student journal Barna: Journal of Student Initiated Research. This course was part of a semester program that took place at Perth in Western Australia. Given the unfortunate occurrence of COVID-19 during this time, students were required to return to their home state and complete their studies online. This meant developing a research project based off previously collected and freely available data. What the students missed out on in terms of field work, they gained from learning how to manage large datasets, larger than what they would have been able to collect themselves in short window of field work. Lectures and weekly meetings with each student allowed for the formulation of project ideas and project design, and students gave feedback to each other which meant they received exposure to a number of different research topics and research methods different from their own.

Since 1947, CIEE has helped thousands of students gain the knowledge and skills necessary to live and work in a globally interdependent and culturally diverse world by offering the most comprehensive, relevant, and valuable exchange programs available. This particular Biology and Ecology Field Studies course has equipped students with knowledge on how to design and conduct an independent research project, how to problem solve and adapt to changing conditions, and how to write a scientific publication.

Thank you to the students and staff for participating in the program and creating a successful and enjoyable experience. To the students, best of luck on your journey through research and discovery and we hope you had a unique and memorable experience in Australia!

Dr Kate Rodger

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FACULTY AND STAFF

Dr Kate Rodger With a background in wildlife conservation Kate’s research areas of interest looks at the social aspects of conservation including governance and protected area planning and management. Past projects include human-wildlife interactions in the marine and terrestrial environment, identifying and minimising visitor impacts through visitor management techniques in protected areas, improving links between science and policy, and integrating ecological and social sciences in nature-based tourism research. A key focus of her work now focuses on exploring human values, perceptions and attitudes, all of which are of particular importance to the sustainable management of

our natural areas.

Dr Alicia Sutton Alicia is a marine scientist specialising in zooplankton and biological . Alicia's research has been conducted primarily throughout the Leeuwin system and she has an in depth understanding of the marine environment and physical processes off the Western Australian coast and the wider Indian Ocean. Alicia has worked on a diverse range of projects involving zooplankton, seagrasses, fishes and cetacean communities, and is an experienced field scientist having collected a variety of biological and oceanographic data from tropical and temperate environments. She also has a keen interest in not-for-profit organisations that have a focus on conserving marine biodiversity.

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STUDENTS

Faith Lundberg Avery Zartarian Oakland University University of Colorado Rochester, Michigan Boulder, Colorado

Jesse Girolamo Wofford College Spartanburg, South Carolina

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TABLE OF CONTENTS

Sea star and sea surface impacts on species richness at Ningaloo Reef

Faith Lundberg..…………………..…...………..1-7.

Rick Stuart-Smith

Plastic pollution patterns on the ocean interface around the northwest and southern coasts of Australia Avery Zartarian……...…………………..……..8-15.

providencetrade.com

Visitation of Lemon Sharks and Blacktip Sharks at Mangrove Bay’s nursery, Ningaloo Reef Jesse Girolamo…..…………….…..…………..16-21.

Daniel Norwood

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RESEARCH PAPER

SeaRESEARCH star and sea PAPERsurface temperature impacts on invertebrate species richness at Ningaloo Reef Faith M. Lundberg - Oakland University - [email protected]

Abstract exception of most corals, many marine are not well understood or Coral reefs contain many diverse species and researched. marine invertebrates play an important but not well understood role in its ecosystem. This Some of the most prevalent research on study examined sea stars and other understanding the roles of marine invertebrate species using a line transect invertebrates dates back to Robert Paine’s survey at various sites around Ningaloo Reef, iconic study of the sea star, Pisaster and acquired remotely sensed temperature ochraceus, in which he discovered its role as data. The analysis showed no increase in sea a keystone species (Paine, 1966). This study star abundance over time, nor did it show any showed the sea star’s importance in relationship between sea star abundance and maintaining diversity in the intertidal region invertebrate species richness. There also by controlling the spread of lower trophic appeared to be no relationship between levels through predation. Ever since, sea stars temperature and abundance or invertebrate have become a species of interest due to their species richness. This could mean that the important role in ecosystems and their Ningaloo Reef system is balanced and interspecific diversity. Sea stars are relatively unaffected by the environmental echinoderms of the class Asteroidea, and faced by other reefs. Ningaloo although often thought to be carnivores which provides an interesting opportunity to feed on bivalves, they can be classified as compare the diversity and resiliency of its omnivores and detritivores (Jangroux & marine invertebrates to other affected reefs Lawrence, 1982). Additionally, some around the world. carnivorous species feed on other sea stars or corals (corallivores), one of the most Introduction voracious being Acanthaster planci, Coral reefs are one of the most well-known commonly known as the crown of thorns sea and diverse ecosystems in the world, and star (COTS). Although a native species, support 30% of all known marine species population explosions of COTS have done (Mather, 2013). Recently, in response to the significant damage to the , growing effects of climate change, many attributing roughly 50% of coral loss to these species of corals and fishes have become outbreaks (Uthicke et al, 2015). flagship species for protecting reef systems Among other anthropogenic factors, climate and bringing awareness to their plights. change appears to be increasing the survival However, there are many other species rate of sea star larvae by 240%, causing their supported by coral reefs that are often population to explode. Climate change has overlooked. It’s estimated that 99% of all also contributed to the bleaching of many animals on earth are invertebrates (Mather, tropical coral reefs, which has been linked to 2013) and these ratios likely extend to the a decrease in species diversity, especially in makeup of a system, yet, with the species which depend on coral reefs for

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Table 1: Names and coordinates of the sites surveyed around Ningaloo.

Site Name Site Coordinates Site Name Site Coordinates A&D’s Dilemma -21.9, 113.94 Monck Head North -23.18, 113.76 Bruboodjoo -22.93, 113.78 Monck Head South -23.16, 113.77 Cardabia Patch -23.1, 113.79 Monck Wall -23.1, 113.76 Coral Bay Central -23.14, 113.75 Pelican -23.33, 113.78 Coral Bay DEC1 -23.13, 113.75 Pelican North -23.32, 113.78 Coral Bay Offshore -23.13, 113.74 Point Maude Inner -23.12, 113.76 Dugong -22.87, 113.76 Point Maude Outer -23.11, 113.75 Kate’s Corner -21.98, 113.92 Oyster Rocks Buoy -23.04, 113.82 Maud RZ1 -23.21, 113.76 Oyster Rocks South -23.05, 113.82 Maud RZ2 -23.21, 133.76 Rick’s Folly -21.92, 113.96 Maud SZ External -23.18, 113.76 Yalobia Bommie -23.2, 113.76 Maud SZ North -23.09, 113.74 Yalobia Passage -23.2, 113.76 Monck Bowl -23.16, 113.76 Yalobia South -23.21, 113.76 Monck Head -23.18, 113.76 Outside Yalobia North -23.19, 113.75 Monck Head Inner -23.18, 113.76 Outside Yalobia South -23.22, 113.75 Monck Head Outer -23.16, 113.76 shelter and food (Letcher, 2009). The rising of invertebrate species richness was predicted to average sea surface continues to decline, since as a keystone species, many sea threaten reefs and the populations which stars regulate the abundance of species in depend on them, and much research has been lower trophic levels. Additionally, due to dedicated to repairing damaged reefs and rising ocean temperatures, it was predicted implementing preventive protections. the abundance of sea stars would increase due to the increased survival rate of larvae in While there have been several studies warmer temperatures, while invertebrate regarding sea stars and climate change at the species richness was predicted to decline in Great Barrier Reef, not as much is known response to coral bleaching. about these factors within the Ningaloo Reef system. Ningaloo Reef has a similar tropical Methods climate to the Great Barrier Reef, as it is Marine invertebrate data was collected at 31 located on the north-western coast of sites around Ningaloo Reef by Reef Life Australia, so it is important to understand Survey divers (Table 1). Data was collected at whether these same risks could impact various times, typically in July and August, in Ningaloo. This study aims to answer the 2010, 2012, 2015, 2016, 2017, and 2019 with following questions about invertebrates and many sites being revisited each year. At each temperature at Ningaloo Reef: (i) is there an site, a 50m transect was surveyed by divers increase in sea star abundance over time? (ii) who swam on either side of the transect and do changes in sea star populations effect recorded invertebrates spotted within 1m invertebrate species richness? (iii) does ocean from the line horizontally and 2m from the temperature effect sea star abundance and line vertically (if there was a cliff or a wall). invertebrate richness? Due to the population Only invertebrates 2.5cm or larger were explosions of COTS at the Great Barrier Reef, counted, including those found in seaweed, it was predicted there would be an increase in crevices, and locations visible without average sea star abundance at Ningaloo Reef moving rocks or boulders. as well. With this increase in abundance,

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8 invertebrate species richness to determine any 7 relationship between the variables. Finally, linear regressions were used to determine any 6 relationships between average sea surface 5 temperature and yearly sea star averages, as 4 well as, invertebrate species richness. 3 2 Results

Average Average Seastar Abundance 1 The descriptive statistics and Shapiro-Wilk 0 test showed each dataset to be normally 2010 2012 2015 2016 2017 2019 distributed, justifying the use of a linear Year regression (Table 2). Although average sea Figure 1. Bar graph which compares the average sea star abundance of each year surveyed at Ningaloo Reef. star abundance did not vary strongly across The error bars are representative of the standard error years (SD = 1.116), 2017 had the lowest of the mean for each year. average sea star abundance of 2.852 (SD = Data containing species in the class 1.116), while 2012 had the highest average Asteroidea was isolated to examine the abundance of sea stars with 6.0 (SD = 1.116). overall average abundance of sea stars for In 2016, the highest average invertebrate each year. Similar methods were used to species richness was 11.2 (SD = 1.053) with calculate the average number of invertebrate 2010 showing the lowest richness of species each year. invertebrate species of 8.118 (SD = 1.053). The highest average sea surface temperature The temperature data was downloaded from recorded was in 2010, with a value of Integrated Marine Observing System (IMOS) 25.911°C, while 2019 had the lowest average at a resolution of 2km x 2km from satellite sea surface temperature of 21.488°C. data. The data was averaged using ArcGIS to determine the temperature of the sea surface When comparing the average sea star at Coral Bay, where the sites are located, abundances from 2010-2019, there appeared to be no significant or strong relationship during the months and years surveyed for 2 invertebrates. between the variables (p = 0.760, R = 0.026). This shows there is no indication of an In order to determine if there was an increase increase in average sea star abundance at in sea star abundance over time, a linear Ningaloo Reef over time (Fig. 1). regression test was applied to the yearly sea star abundance averages using JASP. A linear The linear regression comparing average sea regression test was applied to compare the star abundance and average invertebrate yearly sea star averages and the yearly species richness also showed the relationship

Table 2: Descriptive statistics calculated in JASP. Each Shapiro-Wilk p-value is >0.05, making each of these datasets normally distributed. Dataset Mean Std. dev. Min Max Shapiro-Wilk p-value Average Sea star 4.191 1.116 2.852 6.000 0.651 Abundance Average Invertebrate 9/819 1.053 8.118 11.200 0.694 Species Richness Average Sea Surface 23.507 1.453 21.488 25.911 0.760 Temperature (°C)

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Average Seastar Abundance Average Invertebrate Species Richness Richness Species Invertebrate Average

8 14

7 12 6 10 5 8 4 6 3 4

2 Average Average StarSea Abundance 1 2 0 0 2010 2012 2015 2016 2017 2019 Year Figure 2. Bar graph which compares average sea star abundance to average invertebrate species richness during each year surveyed at Ningaloo Reef. The error bars represent the standard error of the mean. to be insignificant and weak (p = 0.190, R2 = the temperature of the sea and sea star 0.383). This shows the average sea star abundance at Ningaloo Reef (Fig. 3). abundance has little to no effect of the Similarly, the relationship between average richness of invertebrate species at Ningaloo sea surface temperature and average (Fig. 2). However, these variables had the invertebrate species richness was not strong strongest relative relationship. or significant (R2 = 0.299, p = 0.262). The results of the linear regression test Although still very weak, the comparison comparing average sea surface temperature to between sea temperature and invertebrate average sea star abundance was weak and species richness was one of the strongest insignificant (R2 = 0.033, p = 0.730). This relationships relative to the other datasets shows there is likely no relationship between compared. The weakness of the R2 value and p-value show the sea temperature has no

significant effect on the richness of 8 invertebrate species found at Ningaloo Reef 7 R² = 0.0331 (Fig. 4). 6 5 Discussion 4 The efforts of this study found no significant 3 relationships between the variables examined 2 at Ningaloo Reef. There was no indication of 1 an increase in average sea star abundance over

Average Average Seastar Abundance 0 21 22 23 24 25 26 27 time in the regions surveyed, contrary to what Average Sea Surface Temperature (℃) was predicted, nor did the average abundance Figure 3. Scatterplot graph examining the relationship of sea stars appear to have an effect on between sea temperature and sea star abundance at average invertebrate species richness. Ningaloo Reef. The error bars represent the standard Contrary to what was expected, sea surface error of the mean. The linear regression line and R2 temperature also appeared to have no effect 2 value is displayed. The R value shows an extremely on the average abundance of sea stars or on weak relationship between temperature and sea star abundance.

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Barna Volume VI Spring 2019 the average species richness of invertebrates Sea star population explosions have been in the region during the span of this study. linked to commercial overfishing of large predators (Dulvy et al, 2004) which, as stated 14 previously, is regulated. Another factor of R² = 0.2988 12 population explosion is an increase in algae growth due to runoff (Bell, 1992), but due to 10 Ningaloo Reef’s isolation and lack of

8 extensive development, runoff is well managed by the many preventive measures in 6 place (Department of Agriculture, Water and the Environment, 2010). These protections 4 and differences in environment may explain 2 why the results at Ningaloo Reef were unexpected. Average Average Invertebrate Species Richness 0 21 22 23 24 25 26 27 There was also no significant relationship Average Sea Surface Temperature (℃) seen between the average sea star abundance Figure 4. Scatterplot graph comparing sea temperature and average invertebrate species richness at and invertebrate species richness at Ningaloo Reef. The Ningaloo. This may be due to the health of the error bars are representative of the standard error of the reef at Ningaloo. The ecosystem appears to be mean. The linear regression line and R2 value is balanced and protected from human and displayed. environmental pressures which could disrupt There appeared to be no correlation between the order of the reef. If these pressures were average sea star abundance and time. There to impact Ningaloo Reef, there could be was no indication the average abundance had varying effects to the richness of invertebrate changed in the span of time examined, species. One possible outcome would result showing a steady population without growth from a decline in sea star populations due to or decline. This could be due to the differing the factors discussed previously. As shown in environment and protections at Ningaloo Paine’s revolutionary study, sea stars can be Reef. In some regions, such as the Northeast keystone species in marine ecosystems, and Pacific Coast, sea star populations are in their removal leads to a decrease in species decline due to sea star wasting disease diversity as prey species begin to take over (Hewson et al, 2014). However, studies show (Paine, 1966). On the contrary, if populations the frequency of the disease tends to favour were to explode like that of the COTS at the cool sea surface temperatures rather than Great Barrier Reef, invertebrates, such as warm (Menge et al, 2016). This suggests that decapods, could see an increase in species sea star populations are protected from diversity (Leray et al, 2012). However, this decline at Ningaloo due to Ningaloo’s tropical does not take into account the diversity of climate. Additionally, starvation, which is other species on the reef and would likely be cited as another threat to sea star populations limited to non-coral obligate invertebrates (Hewson et al, 2014), is not an issue at (Leray et al, 2012). Likely no relationship was Ningaloo, as commercial and recreational found between the average abundance of sea fishing of sea star prey, such as molluscs, is stars and invertebrate species because the limited (Department of Primary Industries pressures that promote these imbalances are and Regional Development, 2019). not pervasive at Ningaloo Reef. Conversely, the lack of population growth may be due to the same fishing restrictions.

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The comparisons between sea surface thorns sea star as a threat to coral reefs, but temperature and sea star abundance and more research is needed on other species of invertebrate species richness were also found sea stars and invertebrates as not as much is to have no significant relationship. Again, this known about their populations and they have may be due to the relative stability of been shown to be directly affected by climate Ningaloo Reef’s environment. As indicated change stressors (Bos et al, 2008; Leray et al, previously, many measures are in place to 2012; Przeslawski et al, 2008). Going keep Ningaloo Reef healthy and unaffected forward, the implications of this study could by the pressures which threaten other reefs. be far reaching in using Ningaloo Reef as a Climate change and rising ocean temperatures model for a healthy, resilient reef. The results are among the pressures that could threaten seem to show Ningaloo Reef is a balanced the reef and its vulnerable species. However, ecosystem relatively untouched by the steps taken by the Australian Government pressures affecting global reefs and have increased the resiliency of the reef to understanding the qualities which maintain these changes by ensuring the reef is healthy this ideal reef could be used to heal other and not exploited (Department of Agriculture, damaged reefs. Although more understanding Water and the Environment, 2010). is needed, Ningaloo appears to be a promising Additionally, Ningaloo Reef is afforded some example of why these unique ecosystems relief from rising temperatures due to its need continued research and protection for location on the continental shelf where the future generations to appreciate. Ningaloo Current seasonally provides cool Acknowledgements water via (Department of Agriculture, Water and the Environment, I would like to thank Reef Life Survey for 2010). The reef’s resiliency to changing providing the invertebrate data and IMOS for temperatures could explain why, due to the providing the SST data. I would also like to consistency in temperature, there was no thank the CIEE staff for their continued help relationship found between the sea surface and guidance, and specifically Dr. Alicia temperature and sea stars and other Sutton for overseeing and advising during this invertebrates as was predicted. study. While the results of this study provide References valuable information for future research at Ningaloo Reef, the results are limited by the Bell, P. R. F. (1992). Eutrophication and coral reefs-some examples in the Great Barrier span of time surveyed. It would be beneficial Reef lagoon. Water Research, 26(5), 553- to expand the span of time examined beyond 568. https://doi.org/10.1016/0043-1354(92)9 recent years in order to more confidently 0228-V show there have been no climate change related increases or decreases in population Bos, A. R., Gumanao, G. S., Alipoyo, J. C. E., abundance. In the future, more research could & Cardona, L. T. (2008). Population be done on sea stars and threats to them at dynamics, reproduction and growth of the Indo-Pacific horned sea star, Protoreaster Ningaloo Reef, as well as their impact on nodosus (Echinodermata; Asteroidea). other species. Although sea star wasting , 156, 55-63. https://doi.org disease is common in cooler, more temperate /10.1007/s00227-008-1064-2 waters, it may be important to test the range of its impact in order to prevent tropical Department of Agriculture, Water and the species from being affected. Currently, most Environment. (2010). State of Conservation research on sea stars pertains to the crown-of- and Factors Affecting the Property.

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Australian Government. https://www.environ Menge, B. A., Cerny-Chipman, E. B., ment.gov.au/system/files/pages/31a9e336- Johnson, A., Sullivan, J., Gravem, S., Chan, d04a-48cb-810b-6a2b53751ac/files/ningaloo F. (2016). Sea Star Wasting Disease in the -nomination-part4.pdf Keystone Predator Pisaster ochraceus in Oregon: Insights into Differential Population Department of Primary Industries and Impacts, Recovery, Predation Rate, and Regional Development (2019). Ningaloo Temperature Effects from Long-Term Marine Park. Government of Western Research. Public Library of Science One, Australia. http://www.fish.wa.gov.au/Sustain 11(5).https://doi.org/10.1371/journal.pone.01 ability-and-Environment/Aquatic-Biodiver 53994 sity/Marine-Protected-Areas/Pages/Recreat ional-fishing-in-Ningaloo-Marine-Park-.aspx Paine, R. T. (1966). Food Web Complexity and Species Diversity. The American Dulvy, N. K., Freckleton, R. P., & Polunin, N. Naturalist, 100(910), 65-75. https://doi.org/ V. C. (2004). Coral reef cascades and the 10.1086/282400 indirect effects of predator removal by exploitation. Ecology Letter, 7(5), 410-416. Przeslawski, R., Ahyong, S., Byrne, M., https://doi.org/10.1111/j.1461-0248.2004. Wörheide, G., & Hutchings, P. (2008). 00593.x Beyond corals and fish: the effects of climate change on noncoral benthic invertebrates of Hewson, I., Button, J. B., Gudenkauf, B. M., tropical reefs. Global Change Biology, Miner, B., Newton, A. L., Gaydos, J. K., 14(12), 2773-2795. https://doi-org.huaryu. Wynne, J., Groves, C. L., Hendler, G., kl.oakland.edu/10.1111/j.1365-2486.2008. Murray, M., Fradkin, S., Breitbart, M., 01693.x Fahsbender, E., Lafferty, K. D., Kilpatrick, A. M., Miner, C. M., Rainmondi, P., Lahner, L., Uthicke, S., Logan, M., Liddy, M., Francis, Friedman, C. S.,…Harvell, C. D. (2014). D., Hardy, N., & Lamare, M. (2015). Climate Denovirus associated with sea-star wasting change as an unexpected co-factor promoting disease and mass mortality. Proceeding of the coral eating seastar (Acanthaster planci) National Academy of Sciences, 111(48), outbreaks. Scientific Reports, 5(8402). 17278-17283. https://doi.org/10.1073/pnas.1 https://doi.org/10.1038/srep08402 416625111 Jangroux, M. & Lawrence, J.M. (1982). Echinoderm Nutrition. CRC Press. Leray, M., Béraud, M., Anker, A., Chancerelle, Y., & Mills, S. C. (2012). Acanthaster planci Outbreak: Decline in Coral Health, Coral Size Structure Modification and Consequences for Obligate Decapod Assemblages. Public Library of Science One, 7(4). https://dx.doi.org/10.1371 %2Fjournal.pone.0035456 Letcher, T.M. (2009). Climate Change: Observed Impacts on Planet Earth. Elsevier Science & Technology. Mather, J. (2013). Marine Invertebrates: Communities at Risk. Biology (Basel), 2(2), 832-840. https://dx.doi.org/10.3390%2Fbio logy2020832

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RESEARCH PAPER

Plastic pollution patterns on the ocean interface around the northwest and southern coasts of Australia RESEARCH PAPER Avery Zartarian- University of Colorado at Boulder- [email protected]

Abstract late 1950’s, when mass plastic production began, manufacturing has increased globally Ocean pollution and distribution of plastic despite consequences like environmental materials has become a global issue that’s absorption of chemicals and toxic pollutants been widely ignored and under investigated. (Thompson et al., 2009). Pollution of Present day technology gives plastic a wide everyday plastic materials has become an array of characteristics and components that international issue that’s been widely ignored support resilience and global dispersion. To and under investigated. From 2010-2011, investigate plastic trends in marine Australia produced 1,433,046 tons of plastic environments, the present study will examine of which only 20% was recycled (PACIA, the characteristics that appear the most 2011). Concerns heighten as global plastic abundantly in ocean polluted plastic around production exponentially increases, north-western Australia and the difference in generating 600 billion dollars in revenue the surface of plastic between annually, while recycling lags behind. For the northwest and southern regions of example, a study done by Gourmelon (2015), Australia. In total, 178 pieces of plastic were estimates that 22-43% of used plastic is not found in the north-west coastal region and the recycled, leaving its fate to the landfill of dominant characteristics were soft and hard mismanaged waste. plastic, that was white/transparent in colour, within the 0-5 mm class. The expectation of Mismanaged plastic waste from coastline observing higher of plastic in population accumulates an estimated annual the southern region being driven by sum of 31.9 million tons of plastic debris and underlying factors i.e. the Leeuwin Current, of that an estimated 8 million tons are was not so and there was no significant polluted into oceans globally (Ritchie & difference in concentration of plastic between Roser, 2018). Erikson et al. (2014) estimated the two regions. This study identified an that the ocean’s surface water alone contained association between the abundance of plastic five trillion plastic pieces, mostly comprised and the breakdown of its characteristics on of “single use” plastic. Ritchie & Roser the ocean's surface in the northwest region of (2018) found that an estimated 85% of Australia. Surveying the characteristics and Australia's population lives within 50 km of concentrations of plastic is the first step the ocean and although Australia itself isn’t a towards better management of marine large contributor of mismanaged plastic habitats and solidifying patterns of plastic waste, their northern border neighbour, movement. Indonesia, contributes 10.1% to the global accumulation of plastic that pollutes oceans. Introduction Estimated trajectory pathways for plastic Production of plastic gives it a vast array of made by Reisser et al. (2013), suggest that characteristics and components that support plastics have the potential to travel an resilience and global dispersion. Since the immense distance through the influence of

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Barna Volume VI Spring 2019 global gyres and other seasonal currents. Low rates of recycling combined with high rates of plastic distribution are causing plastics to accumulate in aquatic environments and habitats (Reisser et al., 2014). Surveying the characteristics of the most commonly found plastics is the first step to understanding and managing this threat to marine habitats. The western coast of Australia is home to a broad assemblage of marine environments and biota that can be affected by ocean plastic pollution. Its coastline extends a length 12,889 km with ranging dynamic ocean temperatures from the northern tropics to a Figure 1. Sampling sites in both the NW and SC cool temperate climate in the south (Travers regions. et al., 2016). Extensive diversity and productivity of Western Australia’s marine plastic characteristics i.e. size, type and bioregions can be attributed to the coastal colour, that are found in the largest abundance upwelling that’s caused seasonally by the around north-western Australia, and (2) how Ningaloo and Capes current, bringing cool the ocean's surface concentrations (pieces rich nutrient waters north from westerly km−2) of plastic differ between the northwest winds (Feng et al., 2006). The Leeuwin and southern regions of Australia. current dominates surface circulation off the Methods WA coast transporting tropical and subtropical waters south (Rossi et al., 2013), The data was sourced from a total of 16 influencing a span of habitats and species that stations in Australia, nine stations around the otherwise couldn’t spatially coexist i.e. northwest coast, including Ningaloo Reef, tropical coral reefs, mangroves, and rocky and seven spread along the southern coast of southern reefs. The impact that marine debris Australia (Fig. 1). The plastic data was can have on these marine ecosystems is well collected in the month of August in 2011 and known and acknowledged in Australia, but 2012 for both the northwest and south coast the conversation surrounds large items like sites. The data was collected during the day abandoned fishing nets and plastic bags and night time hours, times range from 5:30 (Reisser et al., 2014). While visuals of am to 10:00 pm. animals entangled in pollution gets the Site Description public’s attention, the real threat to food webs and ecosystems is small plastics that animals The data was obtained from freely available are likely to ingest. data online via IMOS-http://imos.org.au/, it was data directly from this study (Reisser et In order to gain a better understanding of al., 2013). To collect pieces of plastic, the ocean plastic pollution off Western Australia ocean surface was skimmed with a neuston and protect the marine environment, this (1.2 x 0.6m) or manta net (1 x 0.17m) and study aims to investigate two things: (1) processed to generate a concentration at each ocean polluted

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coast of Australia a non-parametric Mann- Whitney U test was performed in order to account for the uneven distribution of data from both the North West and South coasts. Results For north west sites, a total of 178 pieces of plastic were collected, ranging in size, type and colour. The dominant characteristics of plastic in the northwest coastal region were soft and hard plastic, that was white/transparent in colour, and within the 0- 5 mm class. A total of 749 pieces of plastic were sampled throughout the 16 stations of the NW and SC regions.

Figure 2. Manta and Neuston Nets. location (pieces km-2) (Fig. 2). Sampling was done in three consecutive 15-minute net-tows at each net site. Replicates were used to measure the variability in concentrations, but also ensured that nets did not become clogged with zooplankton and other organic material.

Sampling Procedure Figure 3. Average number of plastic pieces categorized All the samples of plastic were placed into a into type (hard, soft, line). Standard error bars are tub of seawater and was observed shown. for an hour to help determine plastic type. Plastic Type Each individual sample was then placed into a dish with forceps and was measured, The dominant type of plastic found was hard analysed and photographed. Plastic plastic (with a mean of 8.2 ± 3.3856), closely characteristics were identified by type (hard, followed by soft plastic (with a mean of 8 ± soft, line), colour, and size off the northwest 4.6356), and finally line plastic was the least coast of Australia. Concentrations of plastics abundant (mean of 1.5) (Fig. 3). The data were determined from the volume of water resulted in all Shapiro-Wilk p-values being passing through the net. less than 0.05 deeming it as not normally distributed (Table 1). There were significant Statistical Analysis differences among types of plastic found off An ANOVA was performed in JASP, to the northwest coast (p = 0.039). In particular, compare the difference in abundance of hard, there was a significantly larger abundance of soft and line plastics from the northwest hard and soft plastic, in comparison to line coast. plastic (p = 0.009 and p = 0.025, respectively). There was no significant To access plastic concentration differences difference between hard and soft plastic (p = from the northwest coast and the Southern 0.355) (Table 1).

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Table 1. Descriptive statistics categorized into plastic 25 type (hard, soft, line). Type Hard Line Soft 20

Mean 8.2 1.5 8 15 P-value of 0.001 0.151 <.001 Shapiro Wilk 10

Minimum 1 0 0 5 Maximum 36 4 49 pieces plastic of Average# 0 Std. Error 3.3856 0.4534 4.6356 Size Classes (mm) 0-5 5-10 10-15 15-20 20-30 >30 Std. Dev. 10.706 1.434 14.659

Figure 5. Average number of plastic pieces categorized Plastic Colour into size class (mm). Standard error bars are shown. White/Transparent plastic appeared the most Plastic Size frequently in samples, with a mean Plastic size classes resulted in all Shapiro- abundance of 16.6 ± 25.67 SD (Table 2) (Fig. Wilk p-values being < 0.05, meaning it was 4). Plastic colour resulted in all Shapiro-Wilk not normally distributed excluding the size p-values of less than or equal to 0.008, class of 20-30 mm (Table 4). The size establishing the data set as not normally category of 0-5 had the highest pieces of distributed. There was a significant difference plastic in it, with a maximum of 74 pieces in abundance of plastic categorized by colour collected at one site (Table 4). The mean (p < 0.001), and there was values of concentration categorized by size classes ranged from 0.3 to 12.9 mm (Fig. 5) A Kruskal-Wallis test was used to compare groups and there was a significant difference among plastic abundance in size between eight of the size classes (< 0.05) and a non- significant difference was found between six of the size classes (> 0.05) (Table 5). Plastic Concentration The samples from the north west coast resulted in a mean concentration of 1861.049 pieces km-2 ± 1817.244 SD. The South coast data showed a mean concentration of 3618.337 pieces km-2 ± 5322.987 SD (Fig. 6).

Figure 4. Average number of plastic pieces categorized There was no significant difference found in into colour (black, blue, green, grey, orange, plastic concentrations between the two white/transparent). Standard error bars are shown. regions (p = 0.515). significantly more white/transparent plastic in comparison to all other colours (Table 3).

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Table 2. Descriptive statistics categorized into plastic colours (black, blue, green, grey, orange, Color Black Blue Green Grey Orange White/Transparent Mean 0.1 0.7 0.1 0.2 0.1 16.6 Std Deviation 0.316 0.823 0.316 0.422 0.316 25.67 P-value of Shapiro-Wilk <.001 0.008 <.001 <.001 <.001 <.001 Minimum 0 0 0 0 0 2 Maximum 1 2 1 1 1 87 Mode 0 0 0 0 0 7 Standard error 0.1 0.2603 0.1 0.1333 0.1 8.1175 white/transparent).

Table 3. Comparison between different coloured plastics and significance in differences. Asterisks denote significant differences. Color Black Blue Green Grey Orange White/Transparent Black Blue 0.051 Green 0.5 0.051 Grey 0.357 0.102 0.357 Orange 0.5 0.051 0.5 0.357 White/Transparent <.001* <.001* <.001* <.001* <.001*

Table 4. Descriptive statistics categorized into plastic size class (mm). Size Classes (mm) 0-5 5-10 10-15 15-20 20-30 >30 Mean 12.9 1.1 0.6 0.3 2.4 0.5 Std Deviation 22.248 1.197 0.843 0.657 2.413 0.972 P-value of Shapiro-Wilk <.001 0.028 0.001 <.001 0.08 <.001 Minimum 1 0 0 0 0 0 Maximum 74 3 2 2 7 3 Mode 4 0 0 0 0 0 Standard error 7.0355 0.7630 0.3786 0.2667 0.2134 0.3073

Table 5. Comparison of significant differences in abundance of plastics categorized by size class (mm). Asterisks denote significant differences among different plastic colours. Size Classes 0-5 5-10 10-15 15-20 20-30 >30 (mm) 0-5 5-10 0.028* 10-15 0.003* 0.186 15-20 <.001* 0.046 0.214

20-30 <0.01* 0.01* 0.078 0.265 >30 <.001* 0.024 0.141 0.387 0.367

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type reported in the northwest were mostly hard (46.32%) and soft (45.19%) plastics and line was relatively uncommon (8.47%). Fishing rules throughout Ningaloo Marine Park regulate bag size, take limits, and gear restrictions, which could possibly reduce quantities of line plastic found in this area (Government of western Australia, 2018.). There was a higher abundance of white/transparent (93.3%) plastic located on the surface of the water than the other colours. Figure 6. The mean concentration of plastic in both A study off the coast of Perth found the regions (NW, SC). abundance of plastics to be predominantly Discussion white or clear in colour (Hajbane & Pattiaratchi, 2017). Coloured plastic may be Ocean surfaces, in the northwest coastal more appealing to marine animals, which region of Australia, are dominated with small, would explain why they were less abundant hard and soft plastics, of white or transparent that white/transparent plastics. These results colour. The highest abundance was found to support the original hypothesis that the be plastic fragments smaller than 5 mm, abundance of plastics around Ningaloo Reef which is consistent with microplastics found would possibly be driven by specific on ocean interfaces around the world (Browne characteristics. et al., 2011). The expectation of observing higher concentration of plastic in the Overall, mean ocean surface concentration −2 southwest region being driven by underlying (Cs) 2,837.3 pieces per km is relatively low factors i.e. currents, was not so, and there was compared to previously recorded mean −2 no significant difference in concentration of concentrations of 4256.4 pieces per km in plastic between the northwest and south coast waters around the Australian continent regions. by Reisser et al. (2013). A higher mean plastic concentration occurred along the southern Certain plastic characteristics were found to coast when compared to the northwest coast, be more common off the NW coast of although, data was not consistent and there Australia. Plastics in the size class 0-5 mm was no significant difference. The Leeuwin was highest in abundance. Previous studies Current’s southern movement has been discovered that plastic labelled as observed to bring drifting plastic in northern “biodegradable” doesn’t degrade all the way, regions down the coast of Western Australia instead it creates microplastics, which is a (Reisser et al., 2013). The Leeuwin Current major pathway for the creation of small pieces may account for the distribution of northwest in the ocean (Reiser et al., 2014). This plastic concentrations to the southern coast of degradation occurs through normal activity at Australia and thus help to explain the similar an ocean surface level including, UV concentrations. Other studies found that a exposure, wave and movement actions, majority of plastic is found in the deep sea or oxidation and animal nesting habits distributed across the water column which (Commonwealth Parliament, 2019). may be another factor contributing to why Fragmentation through movement and natural there was no significant difference in sources may explain why there was a higher concentration of plastic on the ocean's surface abundance of plastic between 0-5 mm. Plastic (Choy et al., 2019). An observed that 97% of

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Barna Volume VI Spring 2019 marine species in the south eastern Pacific A., Katija, K., Lisin, S. E., Rolsky, C., Van Ocean interact with marine debris (Thiel et Houtan, K.S. (2019) The vertical distribution al., 2011). Plastic ingestion through marine and biological trans- port of marine life may also affect the concentrations microplastics across the epipelagic and observed. mesopelagic water column. Scientific Reports, 9(1), 7843. Conclusion Commonwealth Parliament, and Parliament An association between the abundance of House. (2019) “Chapter 2; Overview of plastic characteristics and plastic on the Marine Plastic Pollution.” Parliament of ocean's surface in the northwest region of Australia, Commonwealth Parliament. Australia was identified from this study. Tracking plastic movement in the ocean is an Eriksen, M., Maximenko, N., Thiel, M., important matter that arose from this research. Cummins, A., Lattin, G., Wilson, S., Hafner, There was no significant variability in plastic J., Zellers, A., Rifman, S. (2013) Plastic concentrations between the North West and pollution in the South Pacific subtropical Southern coasts sites, which raises the gyre. Marine Pollution Bulletin 68, 71– 76. question of where does the most plastic travel Feng, M., Meyers, G., Pearce, A. & Wijffels, to and why? While there are numerous studies S. (2003) Annual and interannual variations documenting concentrations of plastic on the of the Leeuwin Current at 32°S. Journal of ocean's surface, there is little knowledge on Geophysical Research. 108, 2156–2202. plastic within the rest of the water column which needs to be researched in order to Fish.wa.gov.au/Fishing-and-Aquaculture/ properly manage and conserve marine life. Recreational-Fishing/Recreational-Fishing- Rules/Pages. (2018). Acknowledgements Gourmelon, G. (2015) Global Plastic A special thank you to IMOS- Production Rises, Recycling Lags. http://imos.org.au/ and authors Julia Reisser, Worldwatch Institute (online). Jeremy Shaw, Chris Wilcox, Britta Denise Hardesty, Maira Proietti, Michele Thums, and Hajbane, S., Pattiaratchi, C. B. (2017) Plastic Charitha Pattiaratchi for providing data Pollution Patterns in Offshore, Nearshore and availability. Thank you to Alicia Sutton, Kate Estuarine Waters: A Case Study from Perth, Rodgers, Paul Hollick for their guidance Western Australia. Frontiers in Marine through the research process, advising on all Science data analysis questions and support and the https://doi.org/10.3389/fmars.2017.00063. CIEE program staff for providing the opportunity. Lusher, A. (2015) Microplastics in the marine environment: distribution, interactions and References effects. In: Bergmann M., Gutow L., Klages M. (eds) Marine Anthropogenic Litter. Browne, M. A., Crump, P., Niven, S. J., Springer, Cham. Teuten, E., Tonkin, A., Galloway, T., Thompson, R.C. (2011) Accumulation of PACIA (2011) National plastics recycling microplastic on shorelines worldwide: survey (2010-11 financial year) pp 53. sources and sinks. Environmental Science & Technology 45, 9175–9179. Reisser, J., Proietti, M., Shaw, J., Pattiaratchi, C. (2014) Ingestion of plastics at sea: does Choy, C. A., Robison, B. H., Gagne, T. O., debris size really matter? Frontiers in Marine Erwin, B., Firl, E., Halden, R. U., Hamilton,

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Science 1:70. https://doi.org/10.3389/ fmars.2014.00070 Reisser, J., Shaw, J., Wilcox, C., Hardesty, B. D., Proietti, M., Thums, M., Pattiaratchi, C. (2013) Marine Plastic Pollution in Waters around Australia: Characteristics, Concentrations, and Pathways. PLOS ONE, 8:11, 1-9. Ritchie, H. & Roser, M. (2019) Plastic Pollution. Published online at OurWorldIn Data.org. Rossi, V., Feng, M., Pattiaratchi, C. B., Roughan, M., Waite, A. (2013) On the factors influencing the development of sporadic upwelling in the Leeuwin Current system. Journal of Geophysical Research: Oceans 118, 3608–3621. Thiel, M., Bravo, M., Hinojosa, I. A., Luna, G., Miranda, L., Núñez, P., Pacheco, A. S. Vasquez, N. (2011) Anthropogenic Litter in the SE Pacific: an overview of the problem and possible . Journal of Integrated Coastal Zone Management 11, 115–134. Thompson, R. C., Olsen, Y., Mitchell, R. P., Davis, A., Rowland, S. J., John, A. W. G., McGonigle, D., Russell, A. E.. (2004) Lost at sea: where is all the plastic? Science Magazine 304, 838. Travers, M. J., Potter, I. C., Clarke, K. R., Newman, S. J., Hutchins, J. B. (2010) The inshore fish faunas over soft substrates and reefs on the tropical west coast of Australia differ and change with latitude and bioregion. Journal of Biogeography 37, 148–169.

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RESEARCH PAPER

Visitation of Lemon Sharks And Blacktip Sharks at Mangrove Bay’s Nursery, Ningaloo RESEARCHReef PAPER Jesse Girolamo- Wofford College- [email protected] Abstract Sharks use different habitats at various stages of life and can undergo migration to different Mangrove Bay, a no-take zone in Ningaloo locations in order to feed and reproduce. Reef, Western Australia, acts as a sanctuary Temperature and salinity are the two most zone for sharks to nurse their influential environmental factors affecting young.Exploring the environmental factors shark migration (Bangley et al., 2018). that affect their presence in the reef ecosystem Understanding what range of oceanic is crucial to understanding what draws these temperatures attracts sharks to nursing important predators to the reef ecosystem. grounds is key in predicting how shark Shark detection data for Lemon Shark presence in nursing grounds may change in (Negaprion brevirostris) and Blacktip Shark response to elevated ocean temperatures (Carcharhinus limbatus) from Mangrove Bay caused by climate change. was used to explore relationships with temperature and seasons. While the two Reef sharks spend most of their time in species appear to visit the nursery grounds tropical waters of coral reefs (Michael, 1993), when the ocean surface reaches a specific and Ningaloo Reef, off the coast of Western temperature, there was no significant Australia, is home to a variety of reef shark difference in shark presence acorss season or species. Many studies have investigated no significant relationship with temperature. whale sharks at Ningaloo Reef (Wilson et al., Other environmental factors not explored in 2006; Anderson et al., 2014), but few have this study may be influencing the visitaion of conducted research pertaining to other reef sharks to Mangrove Bay, and more sharks sharks at Ningaloo Reef. Through acoustic need to be tagged and included for seasonal tagging and visual census. a team of data analysis to be more robust. researchers observed temporal and spatial patterns of fours species of reef sharks at Introduction Skeleton Bay, Ningaloo Reef. The study Sharks are apex predators in most marine suggests the different species may have strong ecosystems, and as such, they are critical to spatial overlap in the North end of the Bay. maintaining a habitat’s trophic structure and The long-term inhabitation implies the four health (Frisch et al., 2016). In coral reef species exhibit reproductive aggregation communities, sharks act as apex predators patterns indicating Skeleton Bay may be used (Frisch et al., 2016). They control reef as a nursing grounds (Speed et al., 2011). population and diversity of the trophic levels To investigate Lemon Shark and Blacktip below them, having a top down effect on Shark space use and residency, Oh et al. species diversity and density. While diet (2017) used similar acoustic tracking methods would differ from species to species, they at one of Ningaloo Reef’s nursery areas, generally feed on tropical fish and invertebrates like crab, shrimp, and octopi (Michael, 1993).

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Figure 1. Acoustic Detection Sampling Area from March 2013 to May 2014. Sourced: Google Maps. 2020. Mangrove Bay, which forms the focus of this rocky reefs, coral reefs, algae, mangroves, study. turf-covered reefs, and sandflats. The area is comprised mostly of coral as the coral The primary aim of the study is to explore if provides the food necessary for sharks and detection of Blacktip Sharks and Lemon other organisms to inhabit. Sharks at Mangrove Bay, Ningaloo Reef, is related to changing water temperatures in the Survey design bay. The specific research questions are A) Scientists explored Mangrove Bay Sanctuary were there more tagged sharks detected in Zone from March 2013 to May 2014 by certain months more than others? B) is there a sampling Lemon Sharks and the Blacktip correlation between seasonal temperature Reef Sharks using gill nets and handlines (Oh changes and shark detection? C) what is the et al., 2017). Researchers transferred the optimal temperature for Blacktip Shark and animals into a tank where they then identified Lemon Shark migration to the nursing the species, made observations, and took grounds? It is hypothesized that there will be physical measurements of the organisms. more sharks detected in the warmer summer Lastly, a microchip at the base of the left months. dorsal fin and in the shark’s abdomen along Methods the midline. Each tag transmitted a code specific to that shark. The experiment Study area sampled 36 sharks, however data was Mangrove Bay, located within Ningaloo Reef obtained from only 35 of them (a receiver (21.98°S, 113.98°E) in Western Australia, may have dropped off). A total of 85 acoustic was studied to see if there was a difference in receivers were deployed to track when each the total number of sharks detected seasonally shark visits the nursing grounds. The shark and monthly in relation to ocean temperature data was freely sourced from the Integrated (Fig. 1). Marine Observing System Portal (IMOS- http://imos.org.au/). Temperature data was The tropical waters were surveyed at 113.897 downloaded from IMOS (resolution 2km x °S between 22.003-21.961°E. Ningaloo Reef 2km) and analysed by ArcGIS to analyse consists of many MPA’s (Marine Protected ocean temperature at Mangrove Bay. Areas) including Mangrove Bay (~11.4km2) (Oh et al., 2017). The habitats include bare

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Statistical analysis 16

Data was visually analysed using histograms, 14 graphs, and statistical analysis using Excel 12 and JASP. Individual shark detection and temperature data from March 2013- February 10 2014 was averaged to reveal average 8 temperature and shark detection by season - 6 Autumn, Winter, Spring, and Summer. The of # Detections 4 Shapiro-Wilks test revealed abnormal data, and the data was further analysed using a 2 Kruskal-Wallace Test. The Kruskal-Wallace 0 Test was used to determine if there was a Autumn Winter Spring Summer Seasons significant difference in shark detection across seasons. A correlation analysis was Figure 2. The mean number of sharks detected per performed in JASP to model the relationship season in Mangrove Bay. between monthly shark detection and ocean temperature data at Mangrove Bays’ nursing Shark detection was lowest from August- grounds. October when ocean temperatures are at their lowest (~22°C). In December, sharks visited Results the bay the most when temperatures were Seasonal Shark Visitation to Mangrove Bay’s about 25°C. Shark Nursery To explore the data furthur, a correlation In the Summer, sharks visited the nursing analysis was conducted to determine the grounds more than any other season (11 + 4 strength of the relationship between ocean SE individuals). Less sharks remained in temperature and shark detection (Table 3). Mangrove Bay in the Autumn months (6 + 0.3 Temperature and shark visitation does not individuals). Shark detection droped in the exibit a strong relationship (Spearman’s Rho winter months (4 + 1.6 individuals), then = 0.445, p = 0.147). began to rise again in the spring (5 + 3 Table 1. Mean, standard deviation (SD), and standard individuals). Visitation varies between the error (SE) for seasonal shark detection in Mangrove four seasons (Fig. 2, Table 1). Bay. Despite differences in visitation across Seasons Average SD SE season, a Kruskal Wallace test revealed there was no significant difference in shark visitation to Mangrove Bay across the four Autumn 6.333 0.577 0.333 seasons (p = 0.184). Winter 4.333 2.887 1.667 Monthly Visitation in Relating to Changing Ocean Temperatures Spring 5.000 5.196 3.000 When ocean temperatures were at their lowest, shark visitation is minimal, however, Summer 11.000 6.928 4.000 there is no consistency between ocean temperatures and shark detection in Mangrove Bay (Fig. 3).

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20 35 18 30 16 25

14 C) ° 12 20 10 8 15

# Of Of # Detections 6 10 Temperature( 4 5 2 0 0

Total Shark Detection Temperature

Figure 3. Monthly shark detection in relation to changing ocean temperatures. Table 3. Sea surface temperature (SST) and detection the Spring months than in any other season correlation statistics. (Reyier et al., 2014). Total Given there was no seasonal variablility shark within juvenile shark detection, there was also Variable SST detection no relationship between detection and surface Spearman's ocean temperatre, particularly considering SST Rho - temperature is a key seasonal characteristic.

p-value - Research conducted off Florida’s coast examining shark visitation to nursing grounds Total Spearman's suggests different species have prefered 0.445 - shark Rho temperature ranges and the species exhibit detection p-value 0.147 - seasonal migration patterns to nursing habitats (Kajiura & Tellman, 2016). In

another study conducted in Florida Discussion investigating Blacktip Shark migration to nursing grounds, scientists found water Sharks visited the Mangrove Bay nursery area temperature to be the primary source for the most in the Summer months, though shark seasonal migrations to the nursing grounds visitation does not vary enough to claim (Bangley et al., 2018). In the Atlantic ocean, significant seasonal variability. This could be Lemon Sharks and Blacktip Sharks prefer because as juvenile sharks grow older, they waters ranging from 18-22°C (Reyier et al., visit nursing grounds less frequently. Sharks 2008). Ocean temperature may not be the only tend to revisit the same nursing grounds, but ecological factors contributing to the presense how often they revisit these grounds depends of these sharks in nursing grounds. While sea on the individual; some visit seasonally, and surface temperature may influence shark some visit annually (Oh et al., 2017). In a visitation to Mangrove Bay, this was not study conducted in the Atlantic, evident in this study. Little is known about Carcharhinus limbatus and Negaprion what environmental characteristics influence brevirostris visited nursing grounds more in

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Barna Volume VI Spring 2019 shark migration to Ningaloo’s nursing References grounds (Oh et al., 2017). Anderson, D. J., Kobryn, H. T., Norman, B. This research may not be an accurate M., Bejder, L., Tyne, J. A, & Loneragan, N. representation of shark visitation to Ningaloo R. (2014) Spatial and Temporal Patterns of Reef given the analysis was restricted to the Nature-Based Tourism Interactions with 35 correctly tagged sharks. The analysis Whale Sharks (Rhincodon typus) at Ningaloo would have greatly benefited from a larger Reef, Western Australia. Estuarine, Coastal sampling pool which may have revealed a and Shelf Science 148, 109–119. https:// stronger relationship between visitation, doi.org/10.1016/j.ecss.2014.05.023 seasonality and temperature. Another caveat Bangley, C. W., Paramore, L., Dedman, S., & of the study is the analysis does not include Rulifson, R. A. (2018) Delineation and other environmental variables that may affect Mapping of Coastal Shark Habitat within a shark detection and distribution in Mangrove Shallow Lagoonal Estuary. Plos One 13(4). Bay such as species biodiversity, water https://doi.org/10.1371/journal.pone.019522 salinity, human disturbance, or habitat 1 structure. Although this study does not examine spatial distribution of the tagged Frisch, A. J., Ireland, M., Rizzari, J. R., sharks, previous research suggests N. Lonnstedt, O. M., Magnenat, K. A, Mirbach, acutidens prefer to inhabit mangrove root C. E., Hobbs, Jean-Paul A. (2016) systems within the nursing grounds possibly Reassessing the trophic role of reef sharks as because the complex root system protects apex predators on coral reefs. Coral Reefs 35, juvenile sharks from predators (Oh et al., 459–472. https:// doi.org/10.1007/s00338- 2017). Despite the limitations of this research, 016-1415-2 insight was gained into shark visitation at Mangrove Bay, which is important in Kajiura, S. M. & Tellman, S. L. (2016) understanding how shark visitation to the Quantification of Massive Seasonal nursing gournds may waver in response to Aggregations of Blacktip Sharks climate change. This is essential in (Carcharhinus limbatus) in Southeast understanding how warming ocean Florida. Plos One, 11(3), https:// doi.org/ temperatures may impact the structure of 10.1371/journal.pone.0150911 Mangrove Bay’s delicate ecosystem and Michael, S. W. (1993) Reef sharks and rays of where these apex predators give birth. the world: A guide to their identification, Acknowledgements behavior, and ecology. Sea Challengers. The shark data is sourced from the Integrated Oh, B. Z. O., Thums, M., Babcock, R., Marine Observing System Portal (IMOS- Meeuwig, J. J., Pillans, R. D., Speed, C. W., http://imos.org.au/). The temperature data Meekan, M. G. (2017) Contrasting Patterns of was downloaded from IMOS (resolution Residency and Space Use of Coastal Sharks 2kmx2km and analyzed by ArcGIS to obtain within a Communal Shark Nursery. Marine ocean temmperaure at Mangrove Bay. This and Freshwater Research 68(8), 1501. author would also like to acknowledge Alicia https:// doi.org/10.1071/mf16131. Sutton for her help in constructing the experiment and analyzing the data. Reyier, E. A, Adams D. H., Lowers, R. H. (2008) First Evidence Of A High Density Nursery Ground For The Lemon Shark, Negaprion brevirostris, Near Cape

Canaveral, Florida. Florida Scientist 71(2),

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134–14. https://doi.org/10.1371/journal.pone. 008847024321581 Reyier, E. A., Franks, B. R., Chapman, D. D., Schiedt, D. M., Stolen, E. D. (2014) Regional- Scale Migrations and Habitat Use of Juvenile Lemon Sharks (Negaprion brevirostris) In the US South Atlantic. PLoS ONE 9(2), https://doi.org/10.1371/journal.pone.008847 0. Speed, C., Meekan, M., Field, I., McMahon, C., Stevens, J., McGregor, F., Huveneers C. Berger, Y., Bradshaw, C. (2011) Spatial and temporal movement patterns of a multi- species coastal reef shark aggregation. Marine Ecology Progress Series 429, 261- 275. doi:10.3354/meps09080 Wilson, S. G., Polovina, J. J., Stewart, B. S., Meekan, M. G. (2006) Movements of whale sharks (Rhincodon typus) tagged at Ningaloo Reef, Western Australia. Marine Biology 148(5), 1157-1166. https:// doi.org/10.1007/ s00227-005-0153-8

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