Subantarctic Penguins Habitats and Habits

Most people think of ice and snow when they think of penguins, but most penguins do not live on the Antarctic continent and many seldom see either ice or snow.  Their home is in  the vast Southern Ocean, and they breed on the sub-Antarctic islands.  Only Emperor penguins and Adelies breed on the Antarctic continent itself.  A few others such as King penguins use the Antarctic peninsula, while the rest breed on the tiny sub-Antarctic islands that are scattered around the Southern Ocean or they head for warmer zones such as the coasts of South America and Africa, or even the Galapagos Islands near the equator.

The true habitat of the penguin is the Southern Ocean, where cold Antarctic waters converge with warmer waters moving down from the equator.  In this world-encircling zone, known as the Antarctic Convergence, the seas are rich with plankton and feed a wide variety of life forms from fish to whales to oceanic birds.  In these waters, penguins are so abundant that they make up 90% of the birdlife biomass.  They are perfectly adapted for life in these cold waters.  They use their flipper-like wings to fly through the water to catch their food and their bodies are insulated with fat and feathers against the cold waters.

Penguins spend most of their lives at sea.  They have to be fast and aware, for many predators stalk these waters and are happy to make a meal of a fat juicy penguin.  Killer whales, leopard seals and sharks all take their share of the young and old, the slow and the unwary.  But against these odds, penguins have survived and thrived over millions of years.

They only have to come ashore once a year and just long enough to raise their chicks.  The only connection they still have to the land is that their eggs and chicks must be laid and protected on dry land.  This may be the major limiting factor for penguins, because there are so few bits of land in the vast Southern Ocean.  Besides the Antarctic Peninsula, the southern coasts of Australia and the tips of the South American and African continents, there are only the subantarctic islands:  New Zealand, Heard Island, the Aucklands, the Campbells, and South Georgia to name a few.  These are separated by thousands of kilometers of ocean so nineteen different penguin species have evolved on the different islands.

Some penguins breed on big open rookeries, like the Adelies.  Others, especially the rockhopper penguins, prefer caves, depressions and holes in the ground.  In either case, both parents are involved in the care and protection of the young and usually only one chick or at most two are reared in a breeding season.  One parent sits on the egg while the other goes to sea to feed.  Once the chick hatches, the parents take turns feeding at sea and bringing back their catch to feed the growing chick.  Once the chick is mature and has a covering of thick feathers over a nice layer of fat, it is ready to go to sea.  Parental care ends on the beach and once in the water, the chicks must learn for themselves to feed and avoid predators.

We mostly see pictures of penguins when they are on shore for the breeding season, but the true penguin habitat is the Southern Ocean and their habits have evolved to survive in this rich yet difficult environment.  It is not where one would expect to find birds but there they are, surviving in environments that would kill us in no time.  They make look cute and funny but they are tough little survivors nonetheless.