Most of the time penguins eat
krill and fish. Although there is a lot of
krill in the oceans, the supplies aren't inexhaustible. And as always, people were here very greedy too.
Only by
fishery, 70.000 ton krill is yearly brought up.
That is half of the krill that all seals and seabirds
together catch.
These has, of course, a great impact on penguin population.
According to the American scientist Wayne Trivelpiece, the population of the adelie penguin
decreased by the reduction of krill in their environment. Research showed that one couple
adelie penguins needs 180 kg krill during one breeding season
(from November till begin February). Converted for a colony of 250.000 penguins, it means that
every southern summer 20.000 ton krill is needed. Considering all the breeding pairs
of the adelie penguin in the Antarctic area, this means each summer 56.000 ton krill.
Other fish, also food for penguins, have been
overfished too.
The marble perch, the Antarctic cod and the ice fish have also been caught too much. These fish were used for oil
or worked up to fishmeal.
The African and humboldt penguins are threatened by overfishery of
anchovis and
pilchards.
During the last years this fishery has only increased, meaning a real threat to the penguin population.
next chapter: introducing other outlandish animals