Biology Reference
In-Depth Information
WEATHER: THE GOOD, THE BAD, AND THE UGLY
Only in cartoons do birds lounge atop rainbow colored clouds. In the real world, weather
events may prove beneficial to some birds and harmful to others. Overall, birds are best
adapted to the normal weather patterns of the areas where they have evolved, but birds
usetheirwingstomoveaboutandareconstantlydevelopingnewadaptationstonewcon-
ditions.
Sudden Storms
Forsomebirds,themorerain,thebetter.ThenestingsuccessofSongSparrowsisdirectly
related to precipitation levels, but cool, rainy springs coincide with lower nesting success
for Tree and Cliff swallows.
Storm systems are, and have always been, dangerous for many birds. In the early
1800s, John James Audubon watched as two nighthawks were struck and killed by light-
ning. In 1941, a lightning bolt blasted four Double-crested Cormorants from a flock. All
four died, though their feathers weren't scorched. That same year, more than 50 Snow
Geese were struck by a single lightning bolt. Necropsies revealed that one was badly
burned, but most had died from the impact as they hit the ground.
Manytreesfelledbylightninghavebeenfoundtocontaindeadwoodpeckers,owls,or
other birds. In 1953, two hailstorms in Alberta killed 150,000 ducks and geese. In 1960,
thousands of Sandhill cranes were killed by hail in New Mexico. In 1931, a bluebird pel-
ted by hail in Iowa suffered two broken wings. In 1938, hail killed two California Con-
dors that had been eating a horse carcass. In May 2004, a hail storm killed more than 100
nestingGreatBlueHeronsinnorthernWisconsin.Yeteveninthefaceofthatdevastating
storm, at least 50 herons were unharmed.
Hurricanes can kill birds outright. They can also devastate the vegetation along huge
swathsofshoreline.Andbecausesomanyhouses,garages,industrialplants,gasstations,
sewage facilities, and other human structures can get flooded, toxins and debris can be
released into floodwaters, degrading coastal wetlands even more.
Devastating Droughts
Droughtsandfloodshavealwaysplayedapartinthenaturalworld.Althoughsevereones
can devastate local populations of birds, on a wider scale they've been balanced out by
favorable conditions elsewhere. If climate change alters rainfall patterns so some areas
become consistently drier or moister, this will change the composition of vegetation and
