American White Pelicans: A Peek Into California's Avifaunal Past
Large and white, with a distinctly prehistoric appearance, flocks of American White Pelicans (Pelecanus erythrorhynchos) are one of the great avian sights of California's Great Central Valley, paddling in shallow inland lakes and marshes, and soaring high above on thermals.
Like so many species, the American White Pelican is one that is past its heyday in the Great Central Valley. Historically, flocks of these magnificent birds bred in the southern San Joaquin Valley (Kings, Tulare, and Kern counties) until Tulare Lake and its surrounding wetlands were drained in the 1930's. (Pelicans bred sporadically in the area until 1941, according to Evens and Tait in their Introduction to California Birdlife.) Other former breeding sites include the remote sloughs of the lower Sacramento River, the Salton Sea, and the Colorado River Delta.
Today, their breeding range in California has been reduced to the northeastern corner of the state (largely in Modoc, Siskiyou and Lassen counties) where they breed with regularity at Lower Klamath and Clear Lake National Wildlife Refuges. Outside of California, American White Pelicans breed in the prairie regions of the U.S. and Canada, requiring shallow wetlands and lakes dotted with isolated islands for suitable nesting habitat.
Most populations are migratory, but American White Pelicans can be found in the Central Valley throughout the year, though perhaps more frequently during the fall and winter months. Though American White Pelicans persist in secluded wetlands of the Great Central Valley, their days as breeders here have passed.
Pelicans nest in large colonies and require fairly remote breeding sites with an abundance of food (fish). The entire population of American White Pelicans nests in fewer than 60 colonies. These large birds nest on the ground in areas with good visibility, as they are quite vulnerable to predators during the nesting period, including coyote and foxes, gulls, ravens, Bald Eagles and Great Horned Owls. White Pelicans are able to range widely in order to forage for fish during the breeding season, and studies indicate that pelicans breeding in the Great Basin of western Nevada repeatedly fly over the Sierra Nevada to forage in the Central Valley.
Pelicans feed on fish by scooping them up into the large pouches that hang from their bills, or tipping bottom-up like an enormous duck. After draining the water from their pouch, they swallow the fish whole. Often, groups of pelicans will work together to herd fish into shallow water to make feeding easier. (They do not plunge-dive like coastal Brown Pelicans.)
The primary cause of the decline of American White Pelicans has been habitat loss, as much of their interior freshwater breeding habitat has been drained for land "reclamation" and agricultural endeavors. During the late 1800's and early 1900's, they were also killed in large numbers as they were perceived as competitors to sport fishermen and their plumage was valuable for adorning ladies' hats (much like that of Snowy and Great Egrets).
Loss of habitat for foraging and nesting are still concerns today, as is human disturbance. Almost the entire western population of American White Pelicans passes through the Salton Sea area during the nonbreeding season, which is a cause for some concern. As is the case with all species that gather nearly their entire population together in one place, these great birds are susceptible to catastrophic losses due to disease outbreaks.
American White Pelicans are large birds, with a 9-foot wingspan and weight of nearly 20 pounds. Although they are among the world's heaviest flying birds, they are very elegant in flight, often seen high above soaring gracefully or very slowly flapping their long wings. Frequently, I spot flocks of pelicans flying high, high above the Central Valley, their black-tipped white wings almost too high up to discern with the naked eye.
To see these impressive birds for yourself, head out to one of our local wildlife refuges: I highly recommend Merced or San Luis NWR, where I saw this flock a few days ago. A soaring flock of American White Pelicans is a captivating, prehistoric sight I hope will continue to be common in California's Great Central Valley.
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| American White Pelicans at San Luis NWR |
Like so many species, the American White Pelican is one that is past its heyday in the Great Central Valley. Historically, flocks of these magnificent birds bred in the southern San Joaquin Valley (Kings, Tulare, and Kern counties) until Tulare Lake and its surrounding wetlands were drained in the 1930's. (Pelicans bred sporadically in the area until 1941, according to Evens and Tait in their Introduction to California Birdlife.) Other former breeding sites include the remote sloughs of the lower Sacramento River, the Salton Sea, and the Colorado River Delta.
Today, their breeding range in California has been reduced to the northeastern corner of the state (largely in Modoc, Siskiyou and Lassen counties) where they breed with regularity at Lower Klamath and Clear Lake National Wildlife Refuges. Outside of California, American White Pelicans breed in the prairie regions of the U.S. and Canada, requiring shallow wetlands and lakes dotted with isolated islands for suitable nesting habitat.
Most populations are migratory, but American White Pelicans can be found in the Central Valley throughout the year, though perhaps more frequently during the fall and winter months. Though American White Pelicans persist in secluded wetlands of the Great Central Valley, their days as breeders here have passed.
Pelicans nest in large colonies and require fairly remote breeding sites with an abundance of food (fish). The entire population of American White Pelicans nests in fewer than 60 colonies. These large birds nest on the ground in areas with good visibility, as they are quite vulnerable to predators during the nesting period, including coyote and foxes, gulls, ravens, Bald Eagles and Great Horned Owls. White Pelicans are able to range widely in order to forage for fish during the breeding season, and studies indicate that pelicans breeding in the Great Basin of western Nevada repeatedly fly over the Sierra Nevada to forage in the Central Valley.
Pelicans feed on fish by scooping them up into the large pouches that hang from their bills, or tipping bottom-up like an enormous duck. After draining the water from their pouch, they swallow the fish whole. Often, groups of pelicans will work together to herd fish into shallow water to make feeding easier. (They do not plunge-dive like coastal Brown Pelicans.)
The primary cause of the decline of American White Pelicans has been habitat loss, as much of their interior freshwater breeding habitat has been drained for land "reclamation" and agricultural endeavors. During the late 1800's and early 1900's, they were also killed in large numbers as they were perceived as competitors to sport fishermen and their plumage was valuable for adorning ladies' hats (much like that of Snowy and Great Egrets).
Loss of habitat for foraging and nesting are still concerns today, as is human disturbance. Almost the entire western population of American White Pelicans passes through the Salton Sea area during the nonbreeding season, which is a cause for some concern. As is the case with all species that gather nearly their entire population together in one place, these great birds are susceptible to catastrophic losses due to disease outbreaks.
American White Pelicans are large birds, with a 9-foot wingspan and weight of nearly 20 pounds. Although they are among the world's heaviest flying birds, they are very elegant in flight, often seen high above soaring gracefully or very slowly flapping their long wings. Frequently, I spot flocks of pelicans flying high, high above the Central Valley, their black-tipped white wings almost too high up to discern with the naked eye.
To see these impressive birds for yourself, head out to one of our local wildlife refuges: I highly recommend Merced or San Luis NWR, where I saw this flock a few days ago. A soaring flock of American White Pelicans is a captivating, prehistoric sight I hope will continue to be common in California's Great Central Valley.
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