How long penguins go without food

Feathers are quite important to penguins living around Antarctica during the winter. Emperor penguins Aptenodytes forsteri have the highest feather density of any bird, at feathers per square inch. All but two penguin species breed in large colonies for protection, ranging from to hundreds of thousands of birds.

But living in such tight living quarters leads to an abundance of penguin poop— so much that it stains the ice! The upside is that scientists can locate colonies from space just by looking for dark ice patches. Climate change will likely affect different penguin species differently—but in the Antarctic, it appears that the loss of krill, a primary food source, is the main problem.

In some areas with sea ice melt, krill density has decreased 80 percent since the s, indirectly harming penguin populations. However, some colonies of Adelie penguins Pygoscelis adeliae have grown as the melting ice exposes more rocky nesting areas.

But other species are in trouble, including the erect-crested penguin Eudyptes sclateri of New Zealand, which has lost approximately 70 percent of its population over the past 20 years, and the Galapagos penguin, which has lost more than 50 percent since the s.

Emperor penguins swimming Photo by Polar Cruises Penguins seem a bit out of place on land, with their stand-out black jackets and clumsy waddling. They can move faster through air than water, so will often porpoise to escape from a predator. Photo: Gilad Rom Flickr 4.

Palmer at Cape Washington, at the edge of the ice covering the Ross Sea. It was a short two-day detour in a cruise that lasted for over a month, a trip to one of the most remote and inaccessible populations of animals in the world. Gerald Kooyman walked in front, his eyes adjusting to the dark night.

Even in the faint light reflecting off the snow, Kooyman, a biologist at Scripps Institution of Oceanography, noticed fresh penguin tracks heading from the colony out to sea. Kooyman and his colleagues heard the birds calling to each other, and noticed groups of penguins on their way to or from the sea, and even swimming off the side of the boat.

By all rights, the male birds should have been readying themselves for one of the most intense fasts on the planet, a day marathon of not-eating during which the male incubates a single egg while the female heads out to sea to feed. But in some places, where the sea is close enough to the colony, some of the penguins apparently head out into the dark, wintry waters for a sustaining snack before they get down to the important business of keeping their egg warm.

And this, I think, is an example of that. Kooyman thinks that the behavior might give penguins in these more Northern colonies, closer to the open water, a dietary advantage. The males cannot go out and feed with the egg on their feet. It takes 65 to 75 days for the eggs to hatch — by the time the chicks appear, their fathers have fasted for 4 months! The males rely entirely on the body fat that they laid down during summer to survive the long winter fast.

When the females finally return to the colony in July the males have lost nearly half their body mass and look quite skinny. The females, who having been out hunting all this time, are big and beautiful. Males and females recognise each other by their calls and it is remarkable how quickly a female can locate her mate among thousands of penguins when she comes home.

She has to work quite hard to convince her mate to let her have the egg back or hand over the tiny chick. He has been looking after the egg all winter and although very hungry he is most reluctant to let it go.

The chicks are very small when they hatch weighing only about g to g adult penguins weigh 22 kg to 30 kg at this time of year. They only have a very thin layer of down and are not yet able to regulate their own body temperature.

It takes about 50 days to develop that ability. Until then it is up to the parents to keep the chicks warm. Since they are still very small they fit comfortably in the brood pouch. During the chick rearing period there is a lot of activity in the colony — parents coming and going, chicks looking for anybody willing to feed them — there is a lot of walking around and calling. Both parents take turns brooding their offspring until the youngsters are able to stand on the ice by themselves.

By September, the chicks have grown a thick cover of down and are developing quite rapidly. Growing requires a lot of energy so they are always hungry.

It now takes both parents to go out and gather food for the youngsters. When the little ones are left at the colony they form huddles, especially at night, to keep warm.