Bird Lore: Brown Pelican

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Pelicans are known for their massive, pouched bills that can hold large fish and three gallons of water. The Brown Pelican is a distinctive bird of marine coastal waters. It prefers shallow, nearshore waters and sheltered bays. It can sometimes be seen well out to sea and even occasionally on ponds in the desert Southwest. It arrives in Washington in late spring in what is called a post-breeding dispersal. It occasionally wanders from the outer coast to the inland marine waters. September through November is the most likely time of year to see a Brown Pelican on Puget Sound.

When in groups on the outer coast, the Brown Pelican flies low over the waves in single file of vee formation, with synchronized flapping and gliding. Its diet is made up almost entirely of fish such as menhaden, smelt, and anchovies. Its signature foraging behavior is the plunge dive. It will dive from as high as 60 feet, plunging into the water head first, and returning to the surface with a fish in its bill. It will first tilt its bill downward to drain water from its pouch and then toss its head backward to swallow the fish. While a pelican is draining the water, gulls often try to steal fish right out of its pouch, sometimes while perching on the pelican’s head. Watch a Brown Pelican dive and you will see that it tucks its head and rotates its body to the left. It is thought that this leftward maneuver cushions its trachea and esophagus, which are on the right side of the neck, from the impact of the dive. You can see the leftward twist in this video of plunge diving: www.youtube.com/watch?v=tjo89mgLgHw.

The Brown Pelican nests in colonies. The nest site is on the ground or cliff of an island. On the Gulf Coast it will nest in low trees such as mangroves. The nest can be a simple scrape in the soil, a debris heap with a depression on top, or a large stick nest in a tree. There are usually three eggs incubated by both sexes for about a month. They incubate the eggs with the skin of their feet, standing on the eggs to keep them warm.

Both adults feed the young birds. The adults first regurgitate digested fish onto the nest floor to feed their young. They switch to whole fish when the young are large enough to swallow them. A young bird will thrust its bill into a parent’s throat to force it to disgorge a whole fish. The young remain in a ground nest for about five weeks and up to nine weeks in a tree nest. Although young birds gather in groups, returning parents can recognize their own offspring. Age at first flight has been reported as 9-12 weeks or more.

The oldest Brown Pelican of record was 43 years of age. A young pelican can fly and fend for itself after about three months, but it takes three to five years to reach sexual maturity. The Brown Pelican weighs about seven and a half pounds. Its head-first dive when foraging is unique and not a trait shared with the American White Pelican. There are a number of collective nouns for pelicans that include pod, pouch, scoop, squadron, and rookery. Squadron may be the most common for the Brown Pelican because it looks like a squadron of small aircraft when it flies low over the water in single file or in vee formation.

For conservation purposes, the Brown Pelican is a species of low concern. It represents a conservation success. At the time DDT was in use in the U.S., the Brown Pelican population teetered on the brink of extinction. The chemical endrin killed pelicans outright. As with other birds, DDT caused thin-shelled eggs that broke under the weight of adult birds. Eliminating the use of DDT and other chemical pesticides allowed recovery such that the Brown Pelican is fairly common today. The Brown Pelican remains highly susceptible to human activity because the species breeds, forages, and roosts near shipping channels where oil spills can occur. Abandoned fishing line also threatens this species. In Florida about 700 pelicans die each year after becoming entangled in sport-fishing gear. At this time, Waterbird Conservation for the Americas estimates that there are about 193,000 breeding Brown Pelicans on the continent.

You can listen to the begging calls of juvenile Brown Pelicans here: www.xeno-canto.org/102120.

By Carol Riddell

Carol Riddell manages the bird education displays, on behalf of Pilchuck Audubon Society and Edmonds Parks & Recreation, at the Olympic Beach Visitor Station.

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