Rachel Hickcox, a PhD student in Zoology at Otago University, recently visited Akaroa to speak as part of Sea Week. Rachel is studying the ecology and conservation of penguins and recently wrote an update outlining the foraging patterns of the Hoiho/Yellow-eyed Penguin on Banks Peninsula, which you can read here.
Where are hoiho foraging around Banks Peninsula?
Banks Peninsula is home to a single breeding pair of hoiho (who successfully raised two chicks this year) and several single penguins who have lost mates in recent years. Juvenile hoiho from the Otago Peninsula, North Otago, and the Catlins also frequently travel here in search of prey. But where exactly do hoiho go while at sea? For the first time, hoiho on Banks Peninsula are being tracked using GPS tags, as part of research being conducted by PhD candidate Rachel Hickcox from the University of Otago. Regenerate has funded field costs for Rachel's research, allowing her to come to Akaroa this summer. Pohatu Penguins and many volunteers helped Rachel to deploy these tags, which had been generously sponsored by the Christchurch City Council and the Banks Peninsula Conservation Trust. From the location and dive data collected, Rachel can map the foraging areas that are being used by the penguins. She can determine if environmental conditions dictate where hoiho forage and predict the effect of environmental change on their foraging behaviour. She can also assess how their marine habitat is different than the habitat in Otago, the Catlins, and Stewart Island. Hoiho are highly sensitive to changes in their marine environment, and because they pursue prey on the seafloor, they are restricted to foraging in areas within their maximum dive depth (typically less than about 130m). The type of seafloor substrate is also important because of the type of prey they eat (often blue cod, red cod, opalfish, sprat, and several others). Disturbances to the seafloor due to fishing, as well as food scarcity, entanglement in fishing nets, and the oceanic effects of climate change all threaten hoiho and contribute greatly to their population decline. With the cumulative effect of terrestrial threats such as predation, disease, and unregulated tourism, hoiho could be functionally extinct from the mainland in the next 10 to 20 years. By researching how hoiho disperse at sea, Rachel hopes to identify where potential conflict with humans could occur, either directly (fishing or eco-toursim) or indirectly (environmental change). We can then focus on reducing, or eliminating, these marine threats in these areas.