Yellow-eyed penguins inhabiting Otago Peninsula in New Zealand will be extinct, according to data model predictions, by 2060 unless “immediate, bold and effective conservation measures” are undertaken in a coordinated effort. A new study from the University of Otago presents a strong call to action.
Changes to local New Zealand climate zones account for about one-third of the decline in Yellow-eyed penguin populations. Increasing sea surface temperatures are identified as a primary climate factor. The rest of the decline in penguin numbers is due to human impact.
The new study reported on by Science Daily points out that even though little can be done to immediately halt changing climates, human impact factors can “be managed on a regional level,” according to Dr. Thomas Mattern of the University of Otago. Listen to Mattern talk about the call to action and the factors driving penguin decline on Radio New Zealand – RNZ.
Mattern, the lead study author, identifies human impact factors as fisheries interacting with penguin environments, the introduction on Otago Peninsula of new predators and the intrusion of human disturbance.
Yellow-eyed penguins, listed as endangered by the international conservation union (International Union for Conservation of Nature (IUCN)), are an important attraction in New Zealand’s tourism industry, providing an iconic welcome throughout the country to tourists. Yet a vigorous tourism economy introduces some of the negative human disturbance Mattern identifies. He emphasizes, though, that regional management of human disturbance from tourism can mitigate its negative impact on penguin populations.
Other human impact occurs when fishing nets are set in penguin foraging grounds. Penguins drown in these nets when trapped as unintended bycatch. Penguin marine habitat is degraded through human activity, and penguins are exposed to the human impact of plastics and other toxins in the ocean. Mattern identifies these as factors — human impact factors driving Yellow-eyed penguin extinction — as other factors open to regional management, as reported by Phys Org.
Sixty adult Yellow-eyed penguins died in 2013 because of human factors, contributing to a poor breeding year and leading to poor population replacement. Breeding years 2014 and 2015 — the last year of the long-term study — were consequently also poor. Population models built on the data gathered over the course of the study produce simulations showing Yellow-eyed penguin populations progressively declining, as are Antarctic penguin populations. Study co-author Dr. Stefan Meyer states the model predicts an even grimmer future for local populations, projecting “Yellow-eyed penguins to be locally extinct in the next 25 years.”
Otago Peninsula breeding grounds were formerly active and busy, but now, as observed by veteran penguin researcher Dr. Ursula Ellenberg, “penguin breeding areas [are] now overgrown and silent, with only the odd lonely pair hanging on.” The authors of the study form the conclusion that “Without immediate, bold and effective conservation measures we will lose these penguins from [New Zealand’s] coasts within our lifetime.”
The study, with Thomas Mattern, Stefan Meyer and Ursula Ellenberg as primary researchers, was published in the international journal PeerJ.
