Sunday, November 15, 2009
American White Pelican (Pelecanus erythrorhynchos) Other names: none / Status: FL=stable to increasing slightly, IUCN=LC / Life span: to 31 years / Length: 60-63 in. (152-160 cm) / Wingspan: 96-110 in. (243-279 cm) / Weight: 15.4 lb (7 kg) / Nests: in the summer in Canada and the north-central Great Plains / Found: fall, winter, and early spring months in MZ.
The white pelican is the largest and heaviest bird found on Sanibel. Before its eradication from both islands around 1910, the wild turkey (weighing as much as 24 pounds) would have held this title. The wild turkey was more than likely lost as a result of over-hunting. That being said, however, the white pelican would still have boasted a longer wingspan, measuring nine feet for a mature bird. The white pelican is one of only seven pelican species worldwide; the only other pelican native to North America is the familiar brown pelican. There is one pelican species in South America, the Peruvian pelican, which is similar in appearance to the brown pelican but more than twice as large.
Over the past 20 years the sightings of the white pelican on Sanibel have increased dramatically. In the early 1990s it was found only on remote barrier islands and along oyster bars in northern Pine Island Sound. Today it can be seen regularly off the third culvert along Wildlife Drive in the J.N. "Ding" Darling National Wildlife Refuge, especially during a midwinter low tide.
A stunning bird to observe in flight, the white pelican has conspicuous black tips at the end of its wings and carries one of the largest bills in the world. (The Australian pelican, which is seven pounds heavier and has the same coloration, does in fact have the largest bill of any bird species on earth!) During the nesting season the white pelican develops a large, conspicuous plate on its upper bill. The purpose of the plate is not entirely understood but is believed to be related to breeding displays.
Unlike its brown cousin, the white pelican does not dive for its food. Instead it forms a communal group that herds its catch into shallow water or surrounds a school of minnows, then feeds on them by dipping its large bill into the water and scooping them up. Although it feeds on saltwater fish during the winter months, its primary diet consists of freshwater species such as perch, sunfish, suckers, and carp. As the white pelican's numbers have increased, it has come increasingly in conflict with the growing aquaculture industry in the southeastern United States.
Because of its commanding size, the white pelican has few natural predators. Like many other birds, this pelican was severely impacted by the widespread use of DDT and other pesticides beginning in the 1940s until DDT was banned in the United States in 1972. The white pelican is still recovering from the effects. Despite being a protected species, it is still the target of hunters, its single largest cause of mortality.