The birds migrate north from
California and Mexico
The Daily Astorian
Published on May 22, 2018 12:01AM
Last changed on May 22, 2018
8:39AM
The Wildlife Center of the North
Coast has already cared for several starving young California brown pelicans
this spring.
Brown pelicans, which migrate
north in the spring from nesting colonies off Southern California and Mexico,
spent several decades on the federal endangered species list because of
exposure to pesticides like DDT and other contaminants. Their delisting in 2009
was a success story, but concerns remain about the birds’ continued survival.
Chief among these concerns is the
availability of food.
Anchovy and sardine stocks —
important sources of food for brown pelicans — have collapsed in portions of
the birds’ range. At nesting colonies in the south, researchers are concerned
that lack of food is affecting the pelicans’ productivity. Some researchers
theorize shifting ocean conditions could drive both prey and predators
northward. In the meantime, a northern stock of anchovies remains an important
source of food in the birds’ nonbreeding range, which includes roosts in
Clatsop County.
“That’s a major concern and
threat for this species,” said Michelle McDowell, a biologist with the U.S.
Fish and Wildlife Service.
Brown pelicans have long lives —
with a maximum documented life span of 43 years.
“They don’t have to breed every
year, but making sure they have those food resources, that’s the big story of
making sure this species is going to do well into the future,” she said.
It isn’t uncommon for wildlife
center workers to have starving pelicans on their hands while the birds are up
here. Sometimes pelicans stay north for too long, into late fall and early
winter, and get stuck when food runs out.
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