Yes, I know, I have already covered Gentoo Penguins in this series, but it already needs an update. Last week, this article was published in ‘Ecology and Evolution’ where it was proposed to split Gentoo Penguins in 4 different species. Even though they all look more or less the same (especially to the untrained eye), the study revealed enough difference in their genetics and the length of their bones and the size and shape of their bills to support four different species.
Until now, two subspecies of Gentoo Penguins are recognised: Pygoscelis papua papua and P. papua ellsworthi which the latter breeding on the Antarctic Peninsula and the South Shetland Islands and the former breeding on several subantarctic islands, like South Georgia and the Falkland Islands. This study proposes to promote the Antarctic subspecies (which is slightly larger as the others) to a full species (Pygoscelis ellsworthi). The nominate subspecies would become endemic to the Falklands (P. papua) as that was the place where the species was originally described by Forster in 1781.
Another subspecies of Gentoo Penguins, P. p. taeniata, was sometimes considered on the Kerguelen Islands, however, this was not formally recognised. This study does show enough differences to split this population as well to a full new species (P. taeniata). This study did not look at the populations of the ‘nearby’ Macquarie, Heard and Marion Islands, but former studies indicate these Gentoo Penguins should be the same species, but more study might be needed to establish this.
The Gentoos on South Georgia are proposed to be another species (P. poncetii), which was first officially described in this study.
Why bother, one could ask? Well, apart from birdwatchers who could add a new tick (or some even three) to their list, it might also help their conservation. Especially the populations on South Georgia (P. poncetii) and the Kerguelen (P. taeniata) show declines and it’s often a lot easier to convince authorities to take conservation measures if an endemic species is threatened, as when it’s just a population of a species that also occurs elsewhere.
For now, we first have to wait what science decides, if everything was done correctly, before we can add some new species to our trip lists on our Falklands – South Georgia – Antarctica trips.