For the Birds Radio Program: Brown Pelican
Brown Pelican One of my favorite sights in the world is a line of Brown Pelicans flying so close to the ocean’s surface that they seem to be swallowed into the waves. Flight is easier close to the surface because of reduced drag from something physicists call the ground effect. But when I watch pelicans skimming the waves, I’m not thinking physics. As Walt Whitman said, “You must not know too much, or be too precise or scientific about birds and trees and flowers and water-craft; a certain free margin, and even vagueness—perhaps ignorance, credulity—helps your enjoyment of these things, and of the sentiment of feather’d, wooded, river, or marine Nature generally. I repeat it—don’t want to know too exactly, or the reasons why.” So when I watch pelicans, their mesmerizing wings lead my thoughts into a trance. But I come out of the reverie when I see one plunge-diving head-first from as much as 20 yards above the surface. First, it pulls upright and sticks its legs out. Then it bends its wings at the wrist, transforming itself into a downward-pointing arrow. As it does this, it rotates its body to the left, probably to avoid impact injury to its trachea and esophagus, which are fixed on right side of neck. As its bill enters the water, it thrusts its legs and wings backward, and accelerates toward the fish. The pelican’s amazing gular pouch fills with up to 2 ½ gallons of water, widening to hold it all thanks to bones along the side of the bill bowing out. The streamlined upper bill leads any fish into the pouch, and as the bones of the lower mandible return to an unbowed position, the bill shuts, trapping fish in the pouch. If the dive was unsuccessful, the bird raises its head with bill wide open to drain out the water. If the bird did catch fish, it raises its head more slowly with the closed bill pressed against its breast, allowing water to drain out without the fish escaping. When the water is mostly gone, the pelican swallows the fish with a toss of the head. Brown Pelicans hit the water hard, but fortunately for their internal organs, they have an extensive system of air pouches that cushion them when hitting the water. These air sacs also make them too buoyant to submerge completely. Brown Pelicans are good-natured around people despite all the grief humans have caused their species. In the late 19th and early 20th centuries, they were shot for feathers for the millinery trade, their eggs were over-collected by hobbyists, and they were killed in huge numbers by the fishing industry. They managed to hang on until people started using organochlorine pesticides, especially endrin and DDT. Their population dropped drastically in Texas in the late 1950s, and they were entirely wiped out of Louisiana by 1963—especially ironic because the Brown Pelican is their state bird. In 1975, over 400 pelicans were reintroduced from Florida to Louisiana, but a rapid die-off of about 40% of the introduced birds was blamed on high levels of endrin. Now over 700 die each year in Florida alone from entanglement with fishing gear, and 80 percent of live birds examined in Florida show signs of past encounters with fishing gear. Tough as all this is, these losses at least seem inadvertent and accidental. But for some unfathomable reason, over 100 pelicans were killed or maimed in Brevard Co., FL, during Feb and Mar 1998; some had their necks broken, others had their bills snapped or their wings pinned behind their backs, apparently just for the cruel heck of it. Sometimes I’m ashamed to be a human. But with hard work and a serious effort at cleaning up their waters, Brown Pelicans have become abundant once again. They were one of the first species put on the Endangered Species List in 1970, but in some areas their numbers improved quickly, and in 1985 they were delisted in Alabama, Florida, Georgia, the Carolinas, and the rest of the Atlantic coast. Just last year, thanks to improvements in their numbers in California and along the Gulf coast, they were removed entirely from the Endangered Species List. It seemed good news for pelicans at the time. But I’m afraid the main beneficiaries of their being delisted turn out to be BP and its shareholders, who are saving a lot in fines right now.