Utility of the Little Penguin (Eudyptula Minor) As a Bioindicator of Coastal Metal Pollution
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Utility of the Little Penguin (Eudyptula minor) as a bioindicator of coastal metal pollution Annett Finger M.Sc. Eng (Honours Zoology) A thesis submitted in fulfillment of the requirements for the degree of Doctor of Philosophy Institute for Sustainability & Innovation, College of Engineering and Science, Victoria University November 2016 "We live on the veranda of the world's greatest island and it's our birthright to have a clean ocean, to catch a feed, to interact with nature. And, like any birthright, we have to safeguard it." ― Tim Winton, ABC interview 2012 “Felix believed that the answer to every problem involved penguins; but it wasn't fair to birds, and I was getting tired of teleporting them back home. Somewhere in Antarctica, a whole flock of Magellanic penguins were undergoing psychotherapy.” ― Rick Riordan, The Throne of Fire "Eudyptula minor" - song written by Kiana Day (age 12) - Verse 1- Fish, squid and krill - that's what they all kill, 'cause they're the kings of the sea (not including you and me, and of course the sharks!). - Chorus - Eudyptula minor - you're not small to me, you're the king of the sea and if you disagree, I can prove it to you - just listen! - Verse 2- Who is so small, but packs a fight? Who can kill fish with just one bite? Who lives on our doorstep and just won't mind? - Chorus - Eudyptula minor - you're not small to me, you're the king of the sea and if you disagree, I can prove it to you - just listen! - Verse 3- Some people say you can't fly, but through the waters you glide. and there's no more majestic sight - Eudyptula minor! ii Summary Trace metals are present in all aquatic systems, originating both from natural and anthropogenic sources. With concerns over the environmental impacts of metals, particularly in semi-enclosed aquatic systems such as the Port Phillip Bay, Victoria, Australia, it is important to be able to monitor the degree of pollutant exposure to local organisms. Little Penguins (Eudyptula minor) nesting at St Kilda, only 3 km from the centre of the 3.3 million people metropolis of Melbourne, are a potentially useful bioindicator species for toxicant exposure within Port Phillip Bay because they are resident and feed exclusively within the bay all year around. This study investigated metal and metalloid concentrations in Little Penguins at St Kilda and two other locations with different levels of anthropogenic impact: the penguin parade at Phillip Island and the remote off-shore Notch Island. Non-essential metal and metalloid concentrations in the blood and feathers of Little Penguins during the moult season 2012 were strongly linked to the level of industrialisation adjacent to the respective foraging zones. This trend was more distinct in blood than moulted feathers. Metal and metalloid concentrations in penguin feathers, while potentially biased in this study by external contamination, are a low-impact sampling method, and correlated with whole blood concentrations of mercury, lead and iron. Notably, penguins from the semi-rural Phillip Island colony contained metal concentrations closer to those found in penguins from the remote Notch Island colony, and significantly different from those found in St Kilda’s penguins. This indicated that Phillip Island may be a suitable reference colony for studies investigating iii long-term variation and trends of metal and metalloid pollution within Port Phillip Bay. Next, 157 blood samples were collected from Little Penguins at St Kilda and Phillip Island, over three and two years, respectively, and during three distinct annual seasons (breeding, moulting and non-breeding). Mean blood metal and metalloid concentrations at St Kilda and Phillip Island differed between years and seasons, but were predominantly influenced by location. St Kilda penguins’ mean blood non-essential metal and metalloid concentrations were significantly higher than those found in Phillip Island penguins. Little Penguin body mass and flipper length also differed between the two colonies sampled, with penguins at St Kilda being on average heavier but having shorter flippers. Interestingly, mean blood mercury concentrations showed a negative correlation with penguin flipper lengths. An investigation of blood metal and metalloid concentrations during the different stages of moult provided novel insights into the complex mechanism of non-essential metal mobilisation from internal organs and depuration into new feathers. Most notably, mean mercury concentrations in the blood of St Kilda Little Penguins exhibited an increasing trend over the three years of sampling, whilst decreasing in penguins at the Phillip Island colony over part of that time frame. These variations may reflect differences in temporal metal bioaccumulation or seasonal exposure through prey. To elucidate the link between predator body burden and prey, Little Penguin primary fish prey items were sampled within weeks of penguin blood and faeces collection. This allowed for the comparison of the relative composition of arsenic, mercury, lead and selenium in those matrices. iv Mercury concentrations were highest in the blood, confirming the propensity of this pervasive toxicant to biomagnify in marine trophic chains. Fish and faecal samples contained similar concentrations of arsenic and lead, suggesting faeces as a primary route of detoxification in Little Penguins for those elements. Metal and metalloid concentrations in the sampled fish were generally within the expected limits, except for arsenic and mercury, which were higher than reported elsewhere. Mercury was highest in Australian anchovy (Engraulis australis), which is a primary prey species for St Kilda's Little Penguins. This raises concern for the welfare of this urban dweller, as chronic exposure to even moderate levels of mercury may contribute to sub- lethal effects at a population level. Correlations between paired penguin blood and faecal samples were only significant for selenium, excluding faecal samples as an appropriate sampling matrix for any other element. A preliminary investigation of paired stable isotope ratio and mercury data in penguin blood indicated that observed temporal changes in penguin blood mercury concentrations were not exclusively linked to penguins’ trophic changes in their diet. This suggests that there are other sources of variation of bioavailable mercury within Port Phillip Bay, possibly linked to the bay’s recent undergoing of capital dredging activities. The findings presented in this thesis establish the Little Penguin as an ideal species for the monitoring of contamination in Port Phillip Bay. The results highlighted provide rare baseline data for bioavailable metals and metalloids within the bay and a non-destructive and effective multi-matrix method to monitor a potentially negative pollution impact through trophic exposure. In particular, the temporal trends observed for mercury warrant v long-term surveying in this resident seabird, to ensure the penguins' continued health, conservation and management, as well as to inform future environmental impact investigations. vi Declaration “I, Annett Finger, declare that the declare that the PhD thesis by Publication titled ‘Utility of the Little Penguin (Eudyptula minor) as a bioindicator of coastal metal pollution’ is no more than 100,000 words in length including quotes and exclusive of tables, figures, appendices, bibliography, references and footnotes. This thesis contains no material that has been submitted previously, in whole or in part, for the award of any other academic degree or diploma. Except where otherwise indicated, this thesis is my own work.” Signature: Date: 3rd of November 2016 vii Acknowledgements I gratefully acknowledge Victoria University for awarding a Return-to- study scholarship to myself and allowing me to undertake this study part-time. I am sincerely grateful to Dr. Carol Scarpaci for her constant encouragement and general attitude of 'how hard can it be?' - it has helped me push through many logistical and technical difficulties. Thanks to Dr. Tiana Preston, who generously donated penguin blood samples left over from her PhD and thus, the idea for this project was born. My gratitude goes to Prof. Dayanthi Nugegoda for teaching me the basics of ecotoxicology and co-designing this project. I am grateful to Dr. Patrick-Jean Guay, who taught me much about field sampling, writing ethics and grant applications. Dr. Peter Dann guided me through the world of penguin research and came through each time we needed funding for another batch of sample analysis. To everyone at Phillip Island Nature Parks, especially Andre Chiaradia, Leanne Renwick and Paula Wasiak - thank you for the penguin handling training and support with sampling. Thanks to the late Sherrie Caarels for her support and enthusiasm. This research would not have been possible without Dr. Michael Lynch agreeing to support the ethics application and providing the initial training in venepuncture. Thank you so much to Dr. Bruce Robertson for providing a save space to become confident in this tricky technique. You have been an extraordinary mentor and friend! Thanks to Peter Newgreen, who generously skippered us to remote islands for a portion of the usual price. My sincere thanks also go to Zoe Hogg for allowing me access to the penguins at St Kilda, loaning me equipment and providing data sets. Thank you to everyone at Earthcare St Kilda and Port Phillip EcoCentre, especially Neil Blake. I could ix not have undertaking the field sampling without a large number of volunteers who were tremendously generous with their time in the field, especially my dedicated 'penguin holders' Claire Wallis, Mary Cowling, Ania Fabijańska and Mat Booth! A special thank-you goes to Nikki Kowalczyk for being the best penguin PhD buddy. Doing this project in parallel with you has been fantastic! Your tenacity and generosity are inspiring! Thank you to the expert service and support provided by the technical VU staff, particularly Stacey Lloyd, Joe Pelle, Dr. Sarah Fraser, Charmaine DiQuattro and Min Nguyen. Thanks go to Dr. Randall Robinson, Dr. Mark Scarr and Prof.