Did you know brown pelicans are protected by lots of miniature airbags in their skin, like BubbleWrap ? [View all]

Plunge Diving

Brown Pelicans feed on small, schooling fish in shallow coastal waters. While circling in the air over the sea, a Brown Pelican begins a plunge dive sequence when it spots some fish below. This can start from as high as 65 feet (20 meters) above the water’s surface.
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The bird also twists its body to the left at the last moment. The pelican hits the surface at speeds up to 40 miles per hour. As its long bill pierces the water it throws its wings and legs backward while striking forward with its head, like a snake. The movement of the wings and legs here probably gives some extra acceleration to the head. The gular pouch expands and fills instantaneously with water.



So these pelicans are smashing into the water again and again day after day. The forces involved could be destructive to the delicate tissues of a bird. But pelicans have been doing this for millions of years. It’s no surprise then that they have a suite of adaptations that minimize any negative impacts.

Looking at these adaptations, we can return now to that whole “I’m a pelican and I rotate my body to the left on impact” situation. The best explanation for why Brown Pelicans twist to the left is that the birds are protecting the soft tissues of their trachea and esophagus. These structures are always positioned on the right side of a Brown Pelican’s neck.

Another adaptation that provides protection is a system of air sacs beneath the pelican’s skin. These are concentrated on the bird’s underside. They act like airbags in a car to cushion the impact. Most birds have air sacs, but these are a bit more specialized for plunge diving. Air sacs in pelicans make them extra buoyant too, so these birds can’t dive very deep. They float like inflatable pool toys.
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more: https://www.scienceofbirds.com/blog/pelicans-family-pelecanidae (long, but interesting and readable)


I learned this from an amazing book by Stacey O'Brien, Wesley The Owl, about a flight-impaired barn owl she raised from a chick to the end of his life 19 years later. A truly amazing read.