FOR THE BIRDS?: Are dogs chasing away birds from parks and beaches?
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Since dogs were first trained to hunt birds, relations haven't been especially rosy between the two. Dog walkers and bird watchers have a prickly relationship too, often clashing over the use of recreation areas. And now a new study threatens to inflame tempers even more, suggesting that bird sanctuaries be off limits to even those pooches on short leashes.

Currently, dogs roam triumphant in many places, although the Audubon Society lists bird habitats (in Alaska, California, Oregon, Florida, South Carolina and New Jersey) where it considers dog walking to be a threat. Other areas established to safeguard critically endangered birds, such as the Mississippi Sandhill Crane National Wildlife Refuge along the Gulf Coast, currently allow pups in select pockets as long as they are leashed.

But new research indicates it's a bad idea to let even leashed dogs near their feathered foes. Wildlife ecologists Peter B. Banks and Jessica V. Bryant of the University of New South Wales in Australia report in the journal Biology Letters that dog walking led to a 41 percent decline in the number of birds as well as a 35 percent dip in species diversity in conservation areas and parkland north of Sydney. These drops in abundance and diversity reflect the immediate consequences of dogs passing through the park on trails, however, not long-term effects.

During the week-long study, the researchers found similar results in areas that ban dogs and those that allow them, indicating that even birds accustomed to being around dogs tend to flutter away when they approach.  Perhaps more striking, the scientists say that a leashed dog scared off twice as many birds as a couple of humans strolling though the same park.

"This is useful information,'' Banks says, "because now [officials] have some hard evidence to be able to say, 'You can't have your dogs here and this is the reason why,' whereas in the past they didn't have that."

Banks, who doesn't own a dog but insists he's "not a dog hater," says he launched this research to introduce science into the raging debate over what he calls "walking a predator through the bush." He recalled a recent incident in which a dogged (so to speak) lobbyist brought a city council member to tears while arguing for greater access for man's best friend.

Banks says that Australian, British and Canadian conservationists and government officials have been bombarding him with requests for copies of the study and that individuals in the U.S., Switzerland and Ireland have also expressed interest in it. He was careful to stress that the results do not justify a "blanket banning of dogs" in parks. Banks is currently conducting two follow-up studies: one to compare the impact of dogs on and off leash, and another to gauge the long-term consequences of dog-walking in conservation areas.

There are similar concerns in the U.S. at such places as the Mississippi Sandhill Crane National Wildlife Refuge, where one of North America's rarest birds nest amid the preserve's wet pine savanna. Access here is extremely restricted, because only about a hundred of the red-browed Mississippi sandhill cranes remain. (The Mississippi crane once ranged from western Texas to the Florida panhandle, but its habitat and abundance were already dwindling at the time of the first survey of their population in the 1920s. Today they are typically found only in tiny pockets of Mississippi's Jackson County.)