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to Joanna Burger homepageNEW JERSEY OIL SPILL
Oil spills are a potential threat to the environment along the Jersey shore because both the New York harbor and Delaware Bay are major oil import and export regions. In May of 1996 the Anitra spilled oil which washed ashore. I examined the foraging behavior of Sanderlings (Calidris alba) and Semipalmated Plovers (Charadrius semipalmatus during their spring stop-over period along the Atlantic coast of southern New Jersey following an oil spill. I used a focal animal approach to test the null hypothesis that there are no differences in foraging behavior as a function of the degree of oiling. Nearly 50 percent of the foraging time of shorebirds was interrupted during the main period of beach oiling, primarily by clean-up personnel and vehicles that moved up and down the oiled beach, compared to less than 5 percent of the foraging time at a control beach where birds were interrupted only by walkers and joggers. For both species, the time devoted to feeding decreased significantly as the percentage of oiling increased, while the time devoted to standing about and preening increased significantly as oiling increased. For shorebirds that are already time-stressed in their refueling efforts before their long journey to arctic breeding grounds, these interruptions may prove fatal or might lower reproductive success once they reach the breeding grounds.
Later Nellie Tsipoura and I conducted experiments in the laboratory to determine the effect of the oil. We applied fresh and weathered oil from the Anitra oil spill to the belly feathers of experimental sanderlings (Calidris alba) to simulate 20% plumage oiling, while controls were stroked with clean swabs only. We test the null hypotheses that 1) there are no differences in behavior following oiling, and 2) there are no differences in weight gain or loss in control and experimental birds. Control sanderlings showed no differences in behavior before and after oiling, but oiled birds spent significantly less time resting and more time bathing and preening than did control birds. There were significant differences in weight between the control and oiled birds, and the birds exposed to weathered oil lost more weight than those exposed to fresh oil. Following oiling the sanderlings preened vigorously, spreading the oil so that they appeared to have oiling rates of 30 %, then the percentage of their plumage that was oiled decreased steadily over the next two weeks, but the birds never appeared completely free of oil.