Genetic analysis of the hoiho, also known as the yellow-eyed penguin, has revealed that this species is in fact made up of three distinct subspecies \u2013 knowledge that could be crucial in preventing these rare and notoriously shy birds from going extinct.<\/p>\n
Found solely on the New Zealand mainland and Enderby and Campbell Islands, the hoiho (Megadyptes antipodes) was already a pretty intriguing bird; you can\u2019t miss those bright orangey-yellow eyes, it\u2019s got a shrill call that simply can\u2019t be ignored, and, unusually for penguins, it makes its nest sites under dense vegetation. No wonder it\u2019s won New Zealand\u2019s Bird of the Year<\/a> twice.<\/p>\n It\u2019s also endangered, with the population having significantly declined over the last 30 or so years to the point where it\u2019s now estimated that there are only 2,600 to 3,000<\/a> mature individuals left in the wild, with fewer than 150 breeding pairs<\/a> on the mainland. The continued decline of the species is thought to be driven by a range of factors, including habitat loss and bycatch mortality, though the rise of a disease among hoiho chicks since 2019, known as respiratory distress syndrome (RDS), has also had a significant impact.<\/p>\n Understanding the biological blueprint of endangered species like the hoiho is a critical part of conservation; it can help scientists to see where a species might have vulnerabilities, such as the ability to fight off disease or adapt to changing environments.<\/p>\n<\/p>\n With that in mind, researchers from the University of Otago \u2013 \u014ct\u0101kou Whakaihu Waka, the Department of Conservation, and Ng\u0101i Tahu set to analyzing the DNA of 249 yellow-eyed penguins from across the mainland and Enderby and Campbell Islands.<\/p>\n In the resulting paper, which is a preprint and yet to be peer-reviewed, the team \u201cunexpectedly\u201d discovered evidence within the penguins\u2019 genomes that was \u201cconsistent with recognition of three distinct subspecies.\u201d<\/p>\n Further analysis that compared the genomes with those of two extinct species of penguin<\/a> revealed that these three subspecies were \u201cdeeply divergent lineages\u201d, having separated from each other some time between 5,000 and 16,000 years ago.<\/p>\n The findings may help to explain why the Southern population of hoiho shows no signs of RDS compared to Northern populations, although the study authors say that whether or not genetic differences are involved \u201cremains an open question\u201d that requires further research.<\/p>\n Regardless, it\u2019s hoped that the discovery of three subspecies will help to fine-tune efforts to protect the penguins, particularly with the mainland population being so vulnerable.\u00a0<\/p>\n \u201cRecognising three subspecies acknowledges the cultural and biological diversity within hoiho and ensures conservation efforts that are tailored for each population,\u201d said study author Dr Mel Young, from the Department of Conservation, in a statement<\/a>.<\/p>\n And it\u2019s important that those efforts come as soon as possible. \u201cFor the northern population, extinction is not a distant possibility, it is an imminent threat,\u201d said Lisa Argilla, fellow study author and Dunedin Wildlife Hospital veterinarian. \u201cWithout urgent, bold and collaborative action, we risk losing these precious birds forever.\u201d<\/p>\n