How fast can the penguin swim?
Adélie Penguins over long distances (10s to 100s of miles or km) can sustain speeds of about 5 mph (8 kph). In short bursts, in order to avoid being caught by leopard seals or in pursuing prey, they can move 5-6 times that fast. Unlike flying birds, their wings are adapted to give power on both the up and down stroke of the movement, and their bodies, like fish, are fusiform in shape providing low resistance through the water. They are the most hydrodynamic of all marine creatures. Unlike fish or dolphins, Adélie Penguins can change the shape of their body to suit their swimming speed. They press their feet close to the tail for steering.
What is the purpose of porpoising?
Adélie Penguins can swim very fast under water going a couple hundred yards on one breath, if need be. Otherwise, like cetaceans, when they need to travel long distances they porpoise (leap forward but above the water in order to inhale air as they swim along).This allows breathing without breaking the forward motion and is necessary for long distance swimming.
How long can Adélie Penguins hold their breath underwater, and how deep do they dive?
Normally, Adélie Penguins, while feeding, stay submerged for 2-3 minutes, although the longest recorded submergence is almost 6 minutes. During those 2-3 minutes they most frequently dive to 40-50 m but occasionally to 120-140 m deep; the deepest recorded dive by this species is 170 m. Their heart rate drops from the normal 80-100 beats per min (bpm) to about 20 bpm, and the blood flow to the peripheral (outer) areas of their body is reduced helping to conserve oxygen affixed to blood and muscle protein (hemo- and myoglobin).
