The devastating superstorm that hit the U.S. East Coast this week didn't just wreak havoc on human communities—the spawn of Hurricane Sandy also damaged habitat for coastal bird species. (See "Hurricane Sandy: Why Full Moon Makes 'Frankenstorm' More Monstrous.")
We talked to Bryan Watts, director of the Center for Conservation Biology in Williamsburg, Virginia, to get a bird's-eye perspective on the disaster.
How do birds react to hurricanes?
When birds encounter a storm like this, they're basically in scramble mode just like we are.
Are you worried about birds dying?
We have mortality events with these hurricanes, [especially with] birds that are either migrating or in vulnerable situations. Although surprisingly we have tracked several whimbrels with satellite transmitters that have flown directly through these storms. Last fall, we tracked a whimbrel named Chinquapin right into Hurricane Irene that successfully [landed] in the Bahamas.
Many birds must have lost their homes.
Birds that require low habitats—marshes, beaches, dunes—all of those species would have been displaced. When you see all the water, most of the public thinks about houses and infrastructure. For us we think of birds being displaced. But a lot of [species such as the] barred owl would go completely underwater in storms like that. (See shorebird pictures.)
Does that mean they drown?
Maybe—beaches, dunes, and marshes are teeming with birds this time of year and all of these habitats went underwater, causing inhabitants to seek higher ground. (Also see "Migrating Birds Escaped Worst of Gulf Oil Spill.")
Do the habitats typically recover?
[There can be] fairly long-term habitat effects. If you remember Hurricane Hugo in the 1980s, it had a huge impact on habitat in North Carolina. It pretty much decimated red-cockaded woodpecker habitat [a species that depends on old-growth forests] in the Francis Marion National Forest.
When Hugo came through, it snapped off trees all through what was once the best population [of red-cockaded woodpeckers] at the time. So there are times when hurricanes can hit the wrong place and have lasting impacts on species. Some of the groups we'd expect to be most affected are ones that depend on coastal habitats, such as piping plovers, Wilson's plovers, least terns, etc. The barrier islands that these species use are reshaped and flattened, so their breeding habitat is impacted. (See more bird pictures.)
On the other end we have species that are inconvenienced for a short time like we are, and ride it out like we would.
Any predictions about Sandy's long-term impact on bird habitat?
It looks to me like the main lasting effect of this is going to be a coastal reshaping. It may change some of the outer beach habitats change, and that may last years. All of the marshes within the Mid-Atlantic and all the way up through northern New England went underwater. All of those species would have had to go to higher ground. But that will be a relatively short-term response.
I read that hurricanes can sometimes help ecosystems.
Disturbance is a part of the ecosystem process. It's generally thought that some forests in the [U.S.] Southeast that experience hurricanes regularly [are adapted to hurricanes], so that disturbances are a major proponent of how that community is structured. Hurricanes disrupt habitats and so in that way create a patchwork of different age forests in the landscape and that promotes overall diversity. The further you can [move] away from Hurricane Alley the less that's true—when you get into the Northeast, which is mostly hardwood-based and experiences hurricanes every few decades, hurricanes are not a driving force for how communities are structured, [and hurricanes] can have a lasting effect. (Watch hurricane videos.)
Did bird species evolve to live with hurricanes?
Yes. The best example we have of that is our coastal barrier islands, which go from open sand to dune and even to shrub. A number of our species, such as the federally endangered piping plover, rely on open beach sandy habitats for nesting. Left undisturbed, beaches will progress from open sand to dune grassland to shrubland to forest. It is regular disturbance by storms that keeps beaches open. It sets back their progression to other habitats. In that sense it is a renewal—just as fire reverts forest back to grassland.
How do you think bald eagles are faring after Hurricane Sandy?
New Jersey has a hundred pairs—I suspect they will have lost some trees and nests.
Can birds sense that they should seek higher ground?
Birds are better than we think they are at figuring out ways to survive—I think most of them made it out OK.
颶風後有關鳥的一些有趣的問題和答案.
這些都是很好的事實.
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發表於 2012-11-5 05:31 PM
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