Scientists question 'short-stopping' migrating waterfowl

Waterfowl biologists are expressing some skepticism over a U.S. Fish & Wildlife Service plan to "shortstop" waterfowl to keep the birds from reaching the oil-fouled Gulf of Mexico when their migration begins in the coming weeks.

Their chief concern: Flooding thousands of acres of grain fields across eight states will attract dabblers and offer little benefit to the diver ducks that prefer the bigger waters of the gulf -- where the potentially harmful oil is.

"I kind of think of it as sort of a Hail Mary in a sense," said Dave Luukkonen, a waterfowl biologist with the Michigan Department of Natural Resources and Environment. "There's not been any evidence that we've been able to shortstop ducks in migrations. On the other hand, if it's a milder winter it could possibly keep birds a little farther north. But the main species we're concerned with are those that winter in the coastal region -- lesser scaup, canvasbacks, redheads -- and those aren't the kinds of birds you're going to attract. You're going to attract a fleet of species that are into the freshwater type marshes: Mallards, pintail, teal, gadwall."

Under the plan, federal agencies will spend more than $20 million and work with farmers and other landowners to provide wetland habitat and flooded grain fields in Alabama, Arkansas, Florida, Georgia, Louisiana, Mississippi, Missouri and Texas. In addition, federal waterfowl refuge areas will be planted with rice and flooded. Ducks Unlimited recently received a $2.5 million National Fish and Wildlife Foundation Grant to flood "alternative" habitats in the rice regions of Louisiana and Texas.

USFWS officials in a press release called the effort "unprecented" and said it would benefit numerous species of birds, mammals and reptiles. Calls made to the USFWS for comment were not returned.

Luukkonen said diver ducks are hard-wired to winter in huge rafts on open water. Frank Rohwer, a professor at Louisiana State University and the scientific director for the conservation group Delta Waterfowl, agreed.

"It is the rule that migratory birds go to traditional areas to spend the winter," Rohwer said in a statement issued by DW. "That also applies to most ducks. There are a few ducks, especially mallards, that stay as far north as they can until freezing weather and a lack of food push them to migrate south. That, however, is more the exception rather than the rule. We often have ducks showing up in Louisiana in August and September, long before northern weather would move birds. In the past 25 years we have learned that some of the bay and sea ducks show remarkable homing to the exact same sites to spend the winter."

Rohwer said rather than trying to keep waterfowl off the entire Gulf of Mexico, it might be a better use of resources to focus on "hazing" ducks, or harassing them away from contaminated areas.

"The USDA and others have a long history of using disturbance techniques on certain bird species to alter bird distribution," he added. "The compelling thing about hazing is that the technique would be very focused, because we would haze birds only where there's a problem with oil contamination."

Rohwer acknowledged that hazing isn't easy, but said that Louisiana in particular has a lot of out-of-work fishermen, shrimpers and others who could be mobilized quickly to keep ducks away from contaminated areas.

He also called "nonsense" any discussion about closing duck seasons this year because of the oil spill. He said the existing modest harvest levels would not have a population-level impact even if there was a sizeable die-off from the oil spill.

"If I'm wrong and the Horizon oil spill does kill lots of ducks, the time to alter seasons or limits would be next year. For example, if the 2011 federal duck survey suggests that canvasback numbers are way down, then we might respond by reducing limits or having a species closure. Let's not presuppose a problem that may never materialize."

Luukkonen said there are too many uncertainties at this point to predict what will happen when the migration starts, and didn't rule out the possibility that short-stopping birds could have some benefits.

"If you talk to the people on the front lines down there, there are so many uncertainties," he said. "If nothing else this is going to provide some additional better wintering habitat for dabbling ducks in general, and it's certainly not going to hurt our duck populations."

Rohwer said only time will tell how this year's migration goes.

"The fact is, when blue-winged teal start to show up here in August, no one knows what they're going to find," he said. "We're in uncharted territory."