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© Anchorage Daily News. Friday, July 30,
1999
BIOLOGIST WORRY SEA-DUCK DECLINE WARNS OF ENVIRONMENTAL RISK
The Associated Press San Francisco -
Scientists are warning that dropping numbers of sea ducks could indicate
more widespread ecological decay. The decline comes at the same time that
populations of "puddle ducks," which prefer fresh water, are
growing because of several consecutive wet winters in their breeding
grounds and habitat improvement programs.
Wildlife biologists are alarmed by the decline, especially since sea ducks
were once the most abundant of waterfowl, the San Francisco Chronicle
reported this week. Affected birds include three species of scoters, three
species of eiders, scaup, goldeneyes, oldsquaws and harlequin ducks.
Field researchers point to habitat destruction, pollution and in some
cases, excessive hunting, for the decline. Oceanic warming also may play a
role.
"It's not just about losing some birds," says Bruce Wright,
chief of the Exxon Valdez Oil Spill Office for the National Marine
Fisheries Service in Juneau.
"When bald eagles and ospreys began disappearing, we ultimately found
that the problem was widespread contamination of the freshwater
environment by DDT and other chlorinated hydrocarbon pesticides, something
that had profound implications for human health.
"I think sea ducks are like canaries in the coal mine they're telling
us something is seriously wrong out there."
Wright used to see rafts of up to 15,000 surf scoters big, mostly black
shellfish-eating ducks. "You just don't see that kind of thing
anymore, he said.
One of the factors affecting scoters are contaminants in the marine food
web that are particularly problematic in urban estuaries like San
Francisco Bay, Los Angeles Harbor and San Diego Harbor. Because shellfish
store up pollutants such as petrochemicals and heavy
metals, scoters get megadoses of toxics when they feed in contaminated
waters.
And scoters are running into trouble in their breeding grounds -- the
boreal forests of northern British Columbia, Alberta and Saskatchewan. In
the past 15 years, these vast woodlands have been the site of ambitious
development projects.
"In little more than a decade, about 15 percent of the boreal forests
of northeast British Columbia have been destroyed," said Fritz Reid,
the western North America director of conservation planning for Ducks
Unlimited, one of the nation's largest conservation groups.
"The development is happening at a terrifically rapid rate, and I
think the evidence is pretty clear that it's affecting not only scoters,
but other marine and estuarine ducks (that nest in boreal forests), such
as bufflehead and goldeneye."
Declines of the spectacled eider and Steller's eider have been so profound
that they are now listed as threatened under the federal Endangered
Species Act. Lead poisoning, overexposure to toxic chemicals and hunting
have contributed to the eiders' dwindling numbers, Reid said.
Meanwhile, puddle ducks are at a 50-year high. About 44 million mallards,
widgeon, teal and pintail will be winging their way south from their
breeding grounds in Canada and Alaska this fall.
The robust migration follows several years of slowly recovering
populations after catastrophic lows in the 1970s and 1980s.
Biologists credit two factors in the recovery: a series of consecutive wet
winters in the birds' prime breeding grounds in the Canadian prairies, and
the North American Waterfowl Management Plan, a cooperative venture
between government agencies and farmers in Canada, the United States and
Mexico designed to enhance waterfowl habitat.
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