ANCHORAGE, Alaska (Reuters) - A mysterious disease, possibly a virus, has afflicted ring seals along Alaska's coast, killing scores of them since July, local and federal agencies said on Thursday.
The diseased seals have been beaching themselves on the Arctic coastline since July, with numbers picking up in subsequent months, biologists with the North Slope Borough Department of Wildlife Management and other agencies said.
About 100 of the diseased animals have been found near Barrow, the nation's northernmost community, and half of those have died, the borough biologists reported.
Elsewhere in the sprawling borough, villagers have reported 146 ringed seals hauling themselves onto beaches, and many of those were diseased, the biologists said.
Ringed seals rarely come ashore in normal circumstances, spending most of the year in the water or on floating ice, according to the National Oceanic and Atmospheric Administration's Fisheries Service.
Biologists said they believe the illness was caused by a virus. Symptoms include sometimes-bleeding lesions on the hind flippers, irritated skin around the nose and eyes and patchy hair loss on the animals' fur coats.
They said the mystery outbreak may not be limited to ringed seals. Some dead walruses at Point Hope, a village on Alaska's northwest coast, were found with similar lesions, borough biologists said.
Local hunters also reported finding skin lesions on two bearded seals, the biologists said.
Yet identification of the disease remains elusive, and it was not clear that the lesions found on the walruses were from the same disease that has afflicted the ringed seals, said Bruce Woods, spokesman for the U.S. Fish and Wildlife Service.
"We're kind of in the dark at this point," he said.
The remote locations and other logistical challenges make it impossible to provide veterinary care to beached animals that are sick, said Jason Herreman, a borough biologist.
"Seals that are found dead are collected for sampling. Seals that are sick but alive are being left to recover on their own," he said in an e-mail. Samples were being sent to various laboratories in Anchorage and elsewhere, he said.
Ringed seals, bearded seals and Pacific walruses are all dependent on floating summer sea ice and suffering the impacts of rapid warming in the Arctic, according to federal agencies.
NOAA has proposed listing Alaska's ringed seals and bearded seals as threatened, and the Fish and Wildlife Service has also designated the Pacific walrus as a candidate for Endangered Species Act protections.
Editing by Dan Whitcomb and Cynthia Johnston