Little blue penguins are the world’s smallest penguin, usually weighing slightly over 1 kilogram and standing an average of 33 cm tall. Their plumage is counter-shaded, from black to slate-blue and almost greenish, with bright white underbelly. They spend daylight hours at sea, and if you keep a good look out, especially on a windless day, you will see them on the water surface in the Abel Tasman National Park. Like all penguins they are great swimmers and have been recorded diving to depths of 60 meters and reach speeds of 6 km/hr. They generally dive down 10-20 m to feed on schooling fish, squid and crustaceans. At night they venture ashore, living in underground burrows in rocky coast lines sometimes several metres inland, and notoriously they even burrow under beach-side houses, often keeping the owner’s awake.
They begin breeding when they are 2-3 years old, with both parents working together to incubate and feed their young. One or two eggs are laid and after 36 days of incubation one parent guards the chick(s) while the other collects food. Once the chick is 2 to 3 weeks old, both must go out to collect food as the demand goes up, at this point the chick is particularly vulnerable to predators. At about 4 to 5 weeks the chick leaves the nest and becomes independent. Mortality rate is high in juveniles, but the little blue can live for as long as 25 years.
Between May and June adult birds come ashore to prepare their nests, generally making burrows in rocky caves or crevices, but sometimes under houses and in vegetation. Between November to March adults will come ashore for around two weeks to moult and regrow their waterproof coat. Over this moulting period they are unable to swim and remain onshore. When onshore they are highly vulnerable to predation.
Korora are a New Zealand native, but also in southern Australia where they are often know as Fairy Penguin. While their numbers in NZ are stable or even improving along coastal areas where predator numbers are being controlled, they are currently classified as ‘at risk-declining’. This is mostly due to coastal development and predation. Dogs are their greatest threat, but also cats, ferrets, stoats and set nets. Weka are also known to kill the little blues. Another threat to their survival are powerboats, and it is lucky that the moult co-incides with the busiest boating season. However this does not protect the newly fledged birds, and many dead birds are seen in the park around November and early December. As penguins are poly-phasic sleepers, they can drift off to sleep for short burst day and night, a sleeping penguin could easily be struck. At Tasman Bay Guardians, we believe education and even speed limits should be introduced to protect these fragile inhabitants of the Abel Tasman coastline.
This could be done through regulation, as in the Marine Mammals Protection Regulations, or more preferably a voluntary code of conduct from all the users of the park, to protect the marine seabirds, the park’s marine areas are equally as important as the land, and these should be protected for the benefit of all the park’s inhabitants. The protected coast lines such as the Abel Tasman National Park as well as island sanctuaries are essential in providing safe nesting sites on land, but this is futile if the animal’s foraging habitats aren’t safe-guarded. Speeding vessels, although probably not directly responsible for all of the penguin mortality are a cumulative threat that we have the power to control, therefore is it is not our duty to control it?
Currently Project Janszoon is engaging a post-grad student to monitor nesting success of Korora in relation to terrestrial predators, comparing survival rates of chicks on the mainland compared to a predator free island. It’ll be interesting to see the results of this. There are many opportunities for study in this national park, and in the future, Tasman Bay Guardians hope to engage more students in furthering their careers while making important contributions to the conservation of the Abel Tasman Region.