Week 6
07 August 2006

Penguins - Part II

For any of you who were stumped by a couple of last week’s questions, here are some answers.

Question: On which of the following continents are penguins found: Answer: All of them, South America, Antarctica, and South Africa.

Question: Why don’t polar bears eat penguins? Answer: Polar bears are found at the North Pole. There are no penguins at the North Pole. Polar bears can’t catch penguins because the penguins don’t live where the polar bears do.

Penguins Du Jour –
Gentoos and Emperors

Gentoo Penguins

Gentoo penguin colony Link
Gentoo penguins greet each other. Link	Gentoo penguins Link

Description: Gentoo penguins are medium-sized (third largest penguin). The adult has a dark bluish gray-brown head. The bill is orange red. The most distinctive feature is a triangular while patch extending above and behind the eye, and white eyelids. Gentoos are from 75-90 cm in height and 4.5-8.5 kg in weight.

Distribution: Gentoos are found throughout the Scotia Sea, on the Antarctic Peninsula to 65 degrees S, north to the South Shetland, South Sandwich and South Orkney Islands among others. The estimated population is 314,000 pairs.

Diet:  They eat crustaceans and fish up to 100 m or more below the surface, usually in water within 10 K of land.

Social Behavior: They are highly gregarious. Most individuals stay in colonies year round.

Voice: Gentoos have several calls, chiefly a loud crowing repeated ah aha aha aha e with their head up. The contact call is a short caw.

Conservation: Status – near threatened. Most subantarctic colonies are in decline, possibly as a result of over-fishing of penguin prey. There are a few populations which have doubled within the past two decades.

Historic Penguin Decimation:  In 1577, Sir Frances Drake and his crew sailed around the tip of South America to carry out their plan to attack the Spanish fleet in the Pacific. They sailed through the Strait of Magellan and passed what is now the present day city of Punta Arenas, Chile. Before setting off in the waters of the Pacific, they anchored “to take on wood and water. They also killed 3,000 Magellanic penguins, ‘a very good and wholesome victual’ in one day.”(Murphy, 2004. p89)

Note: I’m sure that’s why we haven’t seen many penguins on this cruise. After Drake passed through the area, any intelligent penguin went into hiding.

As this distant shot of a couple of gentoos proves. penguins can indeed fly. For a few feet anyway! Link

Emperor Penguins

Emperor Penguins
Emperor Penguins	Emperor penguin with chick

Description:  Emperor penguins are the largest penguins. They have bluish heads that changes color to dark bluish-gray on their upper parts. They have long oval-shaped pale lemon-yellow neck patches variably tinged orange. These patches meet on the lower throat where they are almost enclosed by black patches from above and below. They are between 1-1.3 meters in height and 20-41 kg in weight. Because of their streamlined body, they are fast swimmers. Emperor flippers beat 25-50 times per minute. Each beat propels them 2-5 meters.

Question: If a penguin has a flipper beat of 35 beats per minute and each beat propels him 3.5 meters, how far will he swim in 5 minutes?

Distribution: Emperors can be found along the Antarctic coast from 66-78 S. They can endure the coldest conditions of any bird. They are largely found in pack ice, fast ice, and the adjacent seas. Estimated population is 220,000 breeding pairs, mostly in E. Antarctica and the Ross Sea.

Diet: They mostly eat fish, small cephalopods, and crustaceans, captured principally by pursuit diving. They can dive for 15-20 minutes, mostly at 50 m.; however, Emperors have been recorded at depths of 250 and even 500 m.

Social Behavior: Emperor penguins are gregarious. The female lays one egg. Males fast  for 62-67 days while incubating the egg. During this time, the females forage at sea. The females return for the birth of the chick. Males continue taking care of the chick, fasting up to a total of 115 days. During this time they lose approximately 45% of their body weight. Males then go to the sea to feed while the females take care of the chick. The males spend several days at sea and may travel up to 160 km. Afterwards both the male and female penguin provide food for the chick. Chicks fledge at approximately 150 days.

Question: Can you think of any other animals that lose a substantial portion of their body weight during a normal life cycle?

Voice: Colonies are very noisy. Both sexes deliver a rhythmic duet in display kra-aa with their head and neck forward on their breast. The contact call is a single ah note.

Conservation: Emperors are not globally threatened.