Penguins are one of the most threatened groups of seabirds, with 10 of the world’s 18 species listed as Vulnerable or Endangered on the IUCN Red List. At-sea threats, such as the bycatch of penguins in fishing gear has been the subject of few directed studies and has not been fully assessed. In this literature review, researchers assess which species and fishing gear are largest contributers to penguins globally. Authors suggest the accuracy of fully assessing penguin bycatch may be deceptive and quanitative estimates prove difficult as a lack of overall research, publishing bias, and random sampling in areas of precieved conflict or resource availability should be taken into consideration.
Findings of this review identified 14 of the 18 total penguin species were recorded in bycatch events. Gillnets, and to a lesser extent trawls, were shown to pose the greatest threat to penguins. Of the 14 species yellow-eyed Megadyptes antipodes (Endangered), Humboldt Spheniscus humboldti (Vulnerable) and Magellanic Spheniscus magellanicus penguins (Near Threatened) posed as the species of most concern in these bycatch events. Penguins face many threats; reducing bycatch mortality in fishing gear will greatly enhance the resilience of penguin populations to threats from habitat loss and climate change that are more difficult to address in the short term.