Natural La Jolla
By Kelly Stewart
By Kelly Stewart
Looking like fighter planes flying in formation, brown pelicans (
fascinate bystanders as they glide along the coast, riding updrafts and air currents. Even with a wingspan of over 6 feet and an 8-pound body, these birds are extremely maneuverable.
Pelicans nest offshore in colonies on the Channel Islands each year from January through October, with peak nesting occurring in March or April. Plumage is striking in the breeding season, with the end of the bill and part of the pouch turning bright red, the eyes becoming light blue rather than yellowy-white, and a white stripe developing along the length of their necks.
Nests are made of sticks, and are constructed on the ground or in short shrubs, sometimes in trees. Usually they have three eggs, which both parents incubate. Amazingly, pelicans incubate eggs using their webbed feet rather than their feathers, so in effect, they stand on the eggs.
This was a serious problem for pelicans in the late 1960s, when pesticide residues like DDT leached into the environment, contaminating fish. This affected many bird species by thinning the eggshells, making them very fragile. When pelicans then tried to incubate their eggs, the eggs cracked or broke. Due to very low reproductive output and declines in numbers, pelicans were placed on the federal endangered species list in 1970 but were delisted in 2009 (in California) after experiencing a remarkable comeback, once DDT was banned.
Pelican chicks hatch without feathers and look like prehistoric creatures. They remain in or near the nest being fed by the parents for several weeks until they begin to fly (fledge) at about 13 weeks of age.
Gliding along on air currents until they spot their prey (anchovies and sardines mainly), pelicans can quickly take up the head-first plunge position and dive straight down from up to 60 feet in the air. They immediately scoop fish and water into their pouch (the pouch can hold up to 2 gallons of water), tilt their head back to drain the water from the sides of their bill and then swallow the fish whole. Often a group of pelicans will target a big bait ball and several of the birds will keep diving together until they’ve had their fill. Pelicans may live to be 40 years old.
Kelly Stewart, Ph.D. is a postdoc with NOAA’s Southwest Fisheries Science Center. Contact her at NaturalLaJolla@gmail.com.