How far can these juvenile penguins swim?
Juvenile emperor penguins spend most of their first five years at sea apparently and, Happy Feet is likely to spend more time at sea before he returns to the breeding grounds at around 75 degrees south.
The sea voyages of these juveniles have been tracked previously and as the following graph shows they get north as far as 57oS
These are the tracks of six juvenile emperor penguins tracked in 1995 and 1996. The most northerly record from these birds was 57o S (Kooymanet al., 1996). Juvenile emperor penguins have been reported at Macquarie Island (54o S) and in the Beagle Channel near Tierra del Fuego (55o S). So releasing Happy Feet south of New Zealand, while it gives him a fair swim to make it home down around Cape Washington, doesn’t make it impossible. As the graph inset shows the distance Bird 9069 was tracked to easily encompasses the distance to New Zealand, albeit he swam north east not due north!
Now the ocean down in these parts is cold and that acts as a quarantine station so while Happy Feet is making his southern traverse he will be ‘cleansed’ of any remaining nasties so that he arrives back home ready to rock – or whatever penguins of breeding maturity do. And don’t forget we’re going to be tracking him by satellite on his southern traverse.
Thanks to Associate Professor John F. Cockrem, Head of Comparative Physiology and Anatomy at Massey University for providing input to this piece.
Kooyman GL, Kooyman TG, Homing M, Kooyman CA (1996) Penguin dispersal after fledgling. Nature 383, 397-397