Adelie Penguins living at a polynya near the coast of Antarctica Click on image for full size (41K JPG) GSFC/NASA

Scientists have recently discovered that thousands of Adelie Penguins thrive in patches of the chilly Southern Ocean near Antarctica's coastline. In these special areas of the ocean, called polynyas, penguins don't need to travel far to find food.

Much of the shallow ocean near Antarctica is covered with ice, but polynyas are not. That's what makes them special. Polynyas can be very big areas, as big as the state of California, and are usually formed when strong winds blow ice away from the coast, or when ice is blocked by something like an ice shelf, exposing the ocean water.

Without a layer of ice covering it, the ocean water is hit with sunlight and tiny floating algae called phytoplankton grow and multiply very quickly during what is called a plankton "bloom". Phytoplankton is the beginning of the polar ocean food chain, so when it thrives, the animals that eat it do too, as do the animals that eat them!

A tiny, shrimp-like animal called krill eats the phytoplankton. Since there is so much phytoplankton in a polynya, the little krill munch away and reproduce rapidly, becoming very abundant. Krill is the main food for Adelie Penguins as well as other animals such as seals and whales. So, when the krill is abundant, so are the penguins!

Researchers say that they didn't know how much the penguins depended on polynyas before their study. They warn that if the polynyas change, the entire living community would too.

How could thousands of penguins have been hidden from scientists in these ocean oases for so long? The polynyas are impossible to see by ship, even though many of them are quite large, because they are surrounded by ice. Two satellites, NASA's Sea-Viewing Wide Field-of-View Sensor (SeaWiFS) and NOAA's Advanced Very High Resolution Radiometer (AVHRR), provided a way for researchers to get very high quality data about 37 different polynyas over five years.

The satellites provided weekly measurements of the amount of chlorophyll in the polynyas. Chlorophyll is the pigment in plants that makes them green. It allows plants to harness the Sun's energy through photosynthesis to make their own food. If the satellites recorded more chlorophyll in the polynyas, then that meant the phytoplankton were thriving as were the other members of the food chain, the krill and penguins.

Adelie Penguins living at a polynya near the coast of Antarctica Click on image for full size (41K JPG) GSFC/NASA

Scientists have recently discovered that thousands of Adelie Penguins thrive in patches of the chilly Southern Ocean near Antarctica's coastline. In these special areas of the ocean, called polynyas, penguins don't need to travel far to find food.

Much of the shallow ocean near Antarctica is covered with ice, but polynyas are not. That's what makes them special. Without a layer of ice covering it, the ocean water is hit with sunlight and tiny floating algae called phytoplankton grow and multiply very quickly. Phytoplankton is the beginning of the ocean food chain, so when it thrives, the animals that eat it do too, as do the animals that eat them!

A tiny, shrimp-like animal called krill eats the phytoplankton. Since there is so much phytoplankton in a polynya, the little krill munch away and reproduce rapidly, becoming very abundant. Krill is the main food for Adelie Penguins as well as other animals such as seals and whales. So, when the krill is abundant, so are the penguins!

Researchers say that they didn't know how much the penguins depended on polynyas before their study. How could thousands of penguins have been hidden from scientists in these ocean oases for so long? The polynyas are impossible to see from ships because they are surrounded by ice. So, the scientists had to use two satellites to take a look at them.

The satellites provided weekly measurements of the amount of chlorophyll in the polynyas. Chlorophyll is the pigment in plants that makes them green. It allows them to harness the Sun's energy through photosynthesis to make their own food. If the satellites recorded more chlorophyll in the polynyas, then that meant the phytoplankton were thriving. Where there is phytoplankton there is krill and were there is krill there is penguins!

These penguins live near the coast of Antarctica. Click on image for full size (41K JPG) GSFC/NASA

Scientists have been studying special places of the chilly ocean near Antarctica. They found that these places are favorite spots for thousands of penguins!

Much of the ocean near Antarctica is covered with ice, but these special areas are not. That's what makes them special! Without a cover of ice, sunlight can hit the ocean water. This causes tiny floating algae called phytoplankton to grow and reproduce.

A tiny, shrimp-like animal called krill eats the phytoplankton. Since there is so much phytoplankton, the little krill munch away and reproduce until there are tons of them. Penguins like to eat the krill. So, where there are many krill, there are also many penguins!

These special places in the ocean are impossible to see from ships because they are surrounded by ice. So, to study them, scientists used two satellites. The satellites looked at the amount of phytoplankton in the ocean water. Where they found lots of phytoplankton, krill and penguins were living there too!