Oil and diesel fuel from a sunken Argentine ship are devastating biological research along with wildlife in Antarctica, U.S. scientists working there reported Friday.

Biologists who had studied the workings of nature on animals for two decades around Palmer Station, a U.S. research base in Antarctica, now face a manmade disaster that could skew their results for years, said Benhard Lettau, manager of ocean science research for the National Science Foundation."Up to now we've been dealing with the natural variability of the system," Lettau said in a telephone news conference from Palmer Station. "We've introduced non-natural (factors) that will have a severe effect on (animal and plant) populations."

All the newly hatched chicks of south polar skuas, an Antarctic bird slightly larger than a seagull, are expected to die because of the oil spill, Lettau said. Already only a handful remain out of 53 hatchlings originally expected to grow to adulthood in the Palmer study area.

In some cases, the chicks are being killed by adults of their own species. In others, parents are abandoning chicks to the elements. Both types of behavior are abnormal and stem from the oil spill in ways the researchers don't yet understand, said Lettau.

In other incidents of strange animal behavior, young cormorants that normally can fend for themselves are falling prey to predators, and skuas have been observed attacking seals, "which is real unusual," Lettau said.

Penguins also have suffered from the spill, with those covered in oil losing their insulation against the frigid Antarctic waters and others apparently so sickened by eating oil that they fall readily to predators.

No whales have been sighted since the spill, Lettau said, though several had been before the ship ran aground. Whales live on tiny shrimp-like creatures known as krill, thousands of which were found dead in the early days of the spill.

One casualty of the oil spill was an experiment related to the effects of ultraviolet radiation on living things in the Antarctic, according to Peter Wilkniss, NSF's director of polar research. Biologists have been studying microscopic marine plants in the water near Palmer Station to see if they are weakened by the increasing solar radiation that stems from the periodic "ozone hole" that develops each September and October over Antarctica.