Q. Why doesn't seawater harm the gulls
A. They can drink seawater because they have a mechanism for expelling the salt as residue through their nostrils, creating the crusty white flakes sometimes seen on their beaks.
If you see liquid dripping from the end of a gull's beak it is likely the resulting saline solution being secreted
Q. Why cant humans drink seawater
A. Because, unlike seagulls, we don't have a means for expelling the excess salt from our systems and we can't ingest the salts either.
Q. What about marine mammals
A. They don't require much drinking water as very little evaporates from their body since they're surrounded by the stuff. They get all their fluid requirements from the fish they eat.
Q. What do seagulls eat
A. Seagulls are pretty adept at eating anything, either scavenging what's around or catching their own food. They've become particularly skilled at finishing off whatever humans have discarded: chicken bones, waste paper, you name it, causing populations numbers to explode.
They are also feisty, bullying and greedy, snatching the eggs and chicks of puffins and terns and even stealing fish from a pelican's pouch. They also catch clams and fish.
Gulls can safely regurgitate large bones, crab claws and other inedible items not dissolved by digestive juices.
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by Lisa Cardy