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Bad for Birds
Thu Jan 16, 2003
Listen in RealAudio 
Hi, I'm Bryan Yeaton for The Weather Notebook. When El Niño brings storms and droughts
to the US we run for cover. But today reporter Robin White finds out what happens to birds who
can't get in out of the rain.
The Point Reyes Bird Observatory has been catching birds in mist nets five hours a day,
usually five days a week, for 20 years. The Observatory measures, weighs and bands the birds
and releases them back to the wild within about half an hour. Jeff Geupel says the point is to
build up a long history of data to see how birds adapt to changes in the environment.
JP: It takes a 20-year data set to know what's normal, what's highly variable, how birds can
respond to changes in climate. And the last 20 years we have had some of the most extreme
weather in the last hundred, at least in rainfall terms...
The period includes the 1982-83 El Niño which was the wettest on record. Geupel says in
1983 almost no young wrentits reached maturity. He says wrentits like it a bit drier.
JG: In '83 we had those late spring rains -- downpours in May. That can be a big stress on a
juvenile bird who's probably starving to death, doesn't know how to forage yet, gets caught in
one of those downpours and gets cold, and he's gone.
The 1983, El Niño was so wet in the South Pacific that the Galapagos penguin, and the
flightless cormorant too, gave up breeding for that year and their populations plummeted. El
Niño also causes hardship for birds on the East Coast of the U.S., but for a different
reason: drought - both on summer and wintering grounds of migrant birds.
Not all birds have it bad in an El Niño. At Point Reyes, Jeff Geupel says El
Niño means more foliage and some species are better able to hide their nests from
predators. For The Weather Notebook, I'm Robin White.
The Weather Notebook is produced at the Mount Washington Observatory. Generous support comes
from Subaru of America, and the National Science Foundation.
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