DUNEDIN, New Zealand (CN) – One of the rarest penguin species will become locally extinct by 2060 unless conservation actions are implemented immediately, according to a new University of Otago study. The study, published in the international journal PeerJ, examined the plight of yellow-eyed penguins on the mainland of New Zealand.
Other populations of these rare birds are found on sub-Antarctic Auckland and Campbell islands, but the mainland population on New Zealand’s South Island accounts for 40 percent of the estimated 1,700 breeding pairs. These penguins are listed as “Endangered“ by the IUCN Red List, as “Nationally Vulnerable” under the New Zealand Threat Classification System, and as “Threatened” under the U.S. Endangered Species Act (ESA).
“The yellow-eyed penguin was listed as a threatened species under the U.S. Endangered Species Act in 2010 because this rare penguin is facing multiple threats from local fisheries, habitat destruction, introduced predators, and climate change,” said Dr. Shaye Wolf, Climate Science Director at the Center for Biological Diversity, which petitioned the U.S. Fish and Wildlife Service for the ESA listing. “This study provides a strong basis for uplisting the yellow-eyed penguin from threatened to endangered status. But we don’t expect the wildlife-hostile Trump administration to help this penguin in any way. The USFWS is late in doing a 5-year review for the 7 penguin species that were listed in 2010, including the yellow-eyed penguin. Ideally, a robust 5-year review would highlight the severe population declines and slew of threats to the penguins’ survival, and prompt the service to uplist. But that’s very unlikely to happen under this hostile administration without outside pressure and legal action.”
The yellow-eyed penguin, also known by its Maori name hoiho, is the third largest penguin species. It is gray and white, with a yellow stripe from eye to eye crowning its head, and unlike colonial penguins, it nests in seclusion from other penguins. It is a popular tourist draw for New Zealand, and its image adorns many retail items, billboards, and even the NZ $5.00 bill. Climate change and global warming are major threats to the yellow-eyed and other penguins. However, the study notes, there are regional human-caused threats that, if properly managed, could slow the rapid decline of the mainland yellow-eyed population.
“Only about a third of the variation in penguin numbers can be explained by climate factors. Hence, it is clear that other, non-climate factors significantly affect penguin survival rates,” the study notes. “Unlike the effects of climate change, at least some of these non-climatic factors could be managed on a regional scale to enhance the species’ chance for survival.”
The other factors include entrapment of penguins in gill-nets, changes to foraging habitat by bottom fishing, tourism, conversion of breeding habitat to farm land, and pollution.
The mainland population has been studied and well-documented since the mid-1980s. There were three major die-offs in 1989, 2001 and 2012, the causes of which are unclear. “During the last major die-off we actually took comprehensive water samples which showed no indication of a harmful algal bloom. Sea surface temperature can be ruled out as well as the cause of death was determined as toxication. The nature of the toxin remains as of yet undetermined. Technical malfunctions at a sewage plant are a possibility. But we lack the data to find any concrete evidence. Another possibility is agricultural run-off carrying a substance that is toxic to the penguins. In recent years the quality of New Zealand rivers has deteriorated substantially due to the conversion from sheep to dairy farming,” said lead study author Dr. Thomas Mattern of the University of Otago.
Regarding the effects of tourism, Mattern said, “Sites of high importance like Boulder Beach are closed off to the public during the peak breeding season. While this is not really policed due to resource limitations within the NZ Department of Conservation, I would say that these closures are largely being followed by the public. However, there are many other sites where tourists roam freely and are able to run after penguins to grab selfies. I think a bit of visitor education through signage and volunteer wardens would help to improve the situation.”
A lack of observer data in the fisheries contributes to the problem of fully understanding what effect commercial fisheries are having on the penguins. “The fishermen are very protective of their businesses and defensive when it comes to discussions about their potential impact on an endangered species,” Mattern said, “Observer efforts are the most important first step. We need to be able to quantify the effects fisheries indeed have on the penguins. The fishermen need to understand that we’re not out to destroy them. What good would that be if they have no impact on the species whatsoever? But I fear their reluctance could also be an indication that there is actually something they don’t want to come out.”
The study noted that there are documented reports of multiple penguin drowning deaths in gill-net hauls, as high as 12 per year just in the less than two percent of gill-net fisheries being independently observed. “Gill nets are often called a wall of death. They are deployed stationary in the water so that fish get entangled in the mesh. Every movement means that the animals get even more entangled in the net,” Mattern said.
Another problem arises from lack of coordination of management efforts. “There is certainly the problem of yellow-eyed penguins being a high profile species with lots of different interest groups involved, that often do not get along with each other very well. I would go as far to say, that there is some considerable hostility between many key organizations and figures that all want to help the penguins but do not want to have anything to do with one another. What is missing is a leading force that works towards coordinated conservation across the board. The NZ Department of Conservation has been whittled down in recent years to a skeleton and had no resources to do so – even though there is a recovery plan. And NGOs in New Zealand are competing amongst each other for the limited funding available,” Mattern said. “And recent efforts to create Marine Protected Areas have resulted in compromises that in my opinion clearly put fisheries efforts at the top of the priority list.”
The USFWS had no comment and the New Zealand Ministry for Primary Industries, which oversees NZ fisheries, did not respond to requests for comments.
In addition to Dr. Mattern, Stefan Meyer, Melanie Young, Yolanda van Heezik and Philip J. Seddon from the University of Otago, Ursula Ellenberg from La Trobe University in Melbourne, David M. Houston from the NZ Department of Conservation Science and Policy Group, and John T. Darby of the Otago Museum co-authored the study that was published May 16, 2017 in PeerJ.