Although it might not feel like it, the American White Pelican’s (Pelecanus erythrorhynchos) arrival on Sanibel marks the changing of seasons. Unlike the Brown Pelican (Pelecanus occidentalis), a year-round resident of Sanibel, White Pelicans migrate in the fall, usually arriving on Sanibel in October and returning north in the spring. These birds spend the winter months in southern Mexico, southern California, and the Gulf Coast States (Texas, Louisiana, Mississippi, and Florida). During the summer, adults breed in colonies on lakes in western Canada and northwestern U.S.
The white pelican is one of the largest birds in North America. It has a 9-foot wingspan, significantly larger than its cousin, the brown pelican, which has an average wingspan of 7 feet. The white pelicans are all white with black flight feathers only visible when flying. They are found near lakes, marshes and salt bays. During breeding season, they can be found mostly inland, nesting on isolated islands.
White pelicans are very social birds. Pods, or groups of white pelicans, can be seen flying in a V formation. Pods also cooperatively hunt, forcing their prey into shallow waters where they dip their bills into the water and scoop up the fish. They are very buoyant compared to the brown pelicans, which dive for their food. Similar to the brown pelicans, they can hold three gallons of water in their bill but only one gallon in their stomachs, so they have to drain their bills before swallowing the fish.
The population has made a strong comeback since the 1970s due to the EPA banning DDT, a common pesticide used for insect control. It did not cause any physical side effects to the white pelicans, but it caused their eggs to thin. Pelicans stand on their eggs to keep them warm, so when the adult pelicans would stand on the eggs, they would crack and the developing pelican could not survive. This caused a sharp decline in the population until scientists realized the effects DDT was having on the marine food web. Population size has since rebounded for both the brown and white pelican.