Where did all of those king penguins go? | Science News for Students

Where did all of those king penguins go?

It’s unclear what has happened to what was, even a few decades ago, the largest colony of king penguins
Aug 29, 2018 — 6:45 am EST
a photo of a penguin colony, the crowd of penguins can be seen all the way to the horizon

This is a picture of the largest colony of king penguins in 1982. It once hosted some 500,000 pairs of breeding birds each season. Recently discovered losses, though, are so big they could affect the species’ total population.

J.C. Stahl

Since the 1980s, what was once the king of king penguin colonies has lost 85 percent or more of these big birds. It’s a loss of perhaps one in every three of the species’ total population. That’s the finding of a new study.

The penguins live on a sub-Antarctic island in the southern Indian Ocean. It’s called Île aux Cochons (Isle of Pigs). And in its glory days, this island was home to the world’s largest colony of king penguins. Satellite data suggest that back in the 1980s, this island boasted 2 million penguins. Of these, some 500,000 were breeding pairs, says Henri Weimerskirch. He’s a seabird specialist based at the University of La Rochelle, in France, who works for CNRS. (That’s short for Centre National de la Recherche Scientifique. It is France’s national center for scientific research.)

The king penguin population peaked around that time. Since then, things have changed — a lot.

A 2015 satellite analysis showed only 77,000 pairs on the island. A 2016 helicopter survey came up with only 51,000 breeding pairs. Weimerskirch and colleagues shared this unsettling news in the August 2018 Antarctic Science.

The International Union for Conservation of Nature is based in Gland, Switzerland. It identifies species at risk of going extinct. This group has listed king penguins in a category of being least at risk of extinction. That listing may change, Weimerskirch says, “since the species has lost nearly one third of its population.”

King penguins are the second tallest penguins (after emperor penguins). The kings can densely pack themselves into a tight space at breeding time. About two penguins will fit into every square meter (11 square feet, or a square of about 3.3 feet on each side). The panorama of so many birds once was “breathtaking,” Weimerskirch recalls. The underlying ridges in the birds’ home created the illusion of waves in a sea of penguins.

Four other king penguin colonies have changed sizes in a different way. They shrank during tough weather in 1997, Weimerskirch notes. But then they recovered and became stable.  Whatever’s wrong on Île aux Cochons is probably specific to that island, he notes. Its penguins may not have been able to recover from threats such as a weather crisis, invasive cats, diseases or parasites. But that’s only a guess, as researchers haven’t checked out the penguins there in person since 1982. They will need a return visit, Weimerskirch says, if they hope to solve the mystery of the penguin population plunge.

a sattelite image of the Île aux Cochons showing the shrinking boundary of the penguin colony over time

a sattelite map with an outline showing hte boundary of bare ground where penguins used to be

Power Words

(for more about Power Words, click here)

birds     Warm-blooded animals with wings that first showed up during the time of the dinosaurs. Birds are jacketed in feathers and produce young from the eggs they deposit in some sort of nest. Most birds fly, but throughout history there have been the occasional species that don’t.

colleague     Someone who works with another; a co-worker or team member.

conservation     The act of preserving or protecting something. The focus of this work can range from art objects to endangered species and other aspects of the natural environment.

extinction     The permanent loss of a species, family or larger group of organisms.

illusion     A thing that is or is likely to be wrongly perceived or interpreted by the senses.

International Union for Conservation of Nature (or IUCN)     A global network of governments and public organizations based in Gland, Switzerland. IUCN is dedicated to helping the world “conserve the integrity and diversity of nature and to ensure that any use of natural resources is equitable and ecologically sustainable.” The group, created in 1948, is today best known for using science to establish lists of species that may be threatened with (at risk of) extinction or endangered (at imminent risk of extinction).

parasite     An organism that gets benefits from another species, called a host, but doesn’t provide that host any benefits. Classic examples of parasites include ticks, fleas and tapeworms.

penguin     flightless black-and-white bird native to the far Southern Hemisphere, especially Antarctica and its nearby islands.

population     (in biology) A group of individuals from the same species that lives in the same area.

risk     The chance or mathematical likelihood that some bad thing might happen. For instance, exposure to radiation poses a risk of cancer. Or the hazard — or peril — itself. (For instance: Among cancer risks that the people faced were radiation and drinking water tainted with arsenic.)

satellite     A moon orbiting a planet or a vehicle or other manufactured object that orbits some celestial body in space.

sea     An ocean (or region that is part of an ocean). Unlike lakes and streams, seawater — or ocean water — is salty.

species     A group of similar organisms capable of producing offspring that can survive and reproduce.

terrain     The land in a particular area and whatever covers it. The term might refer to anything from a smooth, flat and dry landscape to a mountainous region covered with boulders, bogs and forest cover.

wave     A disturbance or variation that travels through space and matter in a regular, oscillating fashion.

weather     Conditions in the atmosphere at a localized place and a particular time. It is usually described in terms of particular features, such as air pressure, humidity, moisture, any precipitation (rain, snow or ice), temperature and wind speed. Weather constitutes the actual conditions that occur at any time and place. It’s different from climate, which is a description of the conditions that tend to occur in some general region during a particular month or season.

Citation

Journal:​ H. Weimerskirch et al. Massive decline of the world’s largest king penguin colony at Ile aux Cochons, Crozet. Antarctic Science. Vol. 30, August 2018, p. 236.  doi: 10.1017/S0954102018000226.