Impact of gulf oil spill on plovers

Breeding populations of piping plovers exist in three distinct locations -- the Atlantic Coast, the American and Canadian Great Plains, and the Great Lakes -- but birds from all three populations use the Gulf shore as overwintering habitat.

Anticipating the spill's implications for the plover population, the Virginia Tech team began work on the grant application within days of the explosion that caused the oil spill. The first two boats and their crews left Blacksburg for the Gulf the day after the team received notification that its grant proposal had been funded. By the following week, a full team of 28 researchers was collecting data on site.

The team, from the Department of Fisheries and Wildlife Sciences, includes faculty members James Fraser, Sarah Karpanty, and Bill Hopkins, research scientists Daniel Catlin and Jonathan Cohen, and master's student Joy Felio.

When completed, the research will provide data upon which litigators can base settlements for the damage lawsuits resulting from the oil spill. In order to factor damage to plover habitat into these settlements, litigators must know whether and by how much plover survival and migration patterns have changed since the spill.

Fraser, however, would like to see the research used for more than just litigation purposes. "Our real hope," he said, "is that our data will be used for restoration efforts. We want our research to help people think toward the future."

The study will measure survival and migration patterns by comparing rates of survival and emigration in oiled and unoiled areas of the Gulf. Study sites will be limited to areas that historically have had a large number of overwintering plovers.

The team will use a mark-recapture study -- a study in which birds are captured and tagged so that researchers can estimate population characteristics based on the proportion of tagged birds that can be recaptured -- to evaluate the plovers' survival and emigration rates. A separate survey will determine the percentage of plovers that have been oiled as a result of the spill.

The present study is funded by the Interior Department's Natural Resource Damage Assessment Program only through the end of the plovers' spring migration in April, but Fraser, who has been studying piping plovers since they were first listed as threatened in 1986, and Karpanty, who has studied migratory shorebirds for the past six years, plan to pursue funding to extend the research.

"Because the spill was an emergency, the funding came late, and the birds were already on the Gulf when we got there," explained Fraser. "I'm very proud of the fact that we were down there the day after we had funding, but it's possible that birds died before we began to take data."

The explosion of the Deepwater Horizon oil rig on April 20, 2010, killed 11 of the 126 workers on board and released four to five million barrels of oil into the Gulf of Mexico before the well was permanently sealed on Sept. 19. Currently, surface oil affects coastal areas from western Louisiana to Pensacola, Fla., with some tar balls appearing as far west as Galveston, Texas. The area's natural oil-eating microbes, which are abundant partly because smaller spills occur so often in the Gulf, and strong sunlight, which increases photooxidation, offer hope for recovery, but the prognosis for the affected area is still uncertain.