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Good for Birds
Fri Jan 17, 2003
Listen in RealAudio 
Hi, I'm Bryan Yeaton, and this is The Weather Notebook. Some bird species face hardship during
El Niño years. Today reporter Robin White tells us birds in Oregon and Washington do
very nicely, thank you, when El Niño rolls around.
It's fall and out in a marsh at Point Reyes California, bird ecologist Phil Nott is watching a
bird begging for food in a bush.
PN: The wings were just sort of flapped down really low and just flicking...
RW: And that means?
PN: That's normally begging behavior. It's kind of late for begging.
Nott, who works with the Institute for Bird Population, is attuned to behavior that's out of
season because when birds can extend the breeding season they can have more young. He's found
that during wet El Niño years migratory birds in the Pacific Northwest have three times
as many young as in dry La Nina years. He says one of the ways they might do it is by getting
back early from over-wintering. Sometimes they get back up to three weeks early.
PN: Birds have a window of opportunity. There's only so many months they can breed in, and
conditions have to be favorable... If a bird arrives early, the chances of pulling off one or
two or even three broods is increased.
The birds are coming from Western Mexico where they spend the winter. And during El
Niño years this area gets earlier rain. Nott speculates that might produce more insects
that help the birds fatten up for their two-thousand-mile journey. [The birds are better
hydrated. And they might benefit from prevailing winds which, during El Niño years blow
directly to the north, helping them on their return trip to Oregon and Washington.] Whatever
the mechanisms, fewer birds die in migration during El Niño years and they lay more
eggs when they get back. For The Weather Notebook, I'm Robin White.
The Weather Notebook is produced by The Mount Washington Observatory, with support from
Subaru, and The National Science Foundation.
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