The National Oceanic and Atmospheric Administration declared a recent rash of seal deaths to be an "unusual mortality event" on Tuesday. More than 60 seals have died and 75 found diseased in Alaska with skin sores and patchy hair loss. The Fish and Wildlife Service has also identified diseased and dead walruses. A similar official declaration for Pacific Walrus in Alaska is pending. The walruses have suffered from similar symptoms, which have also included labored breathing and appearing lethargic. Scientists have yet to identify a cause for this disease, but tests have indicated that it is not a virus. Hunters, meanwhile, continue to see many healthy animals. Despite a significant contact with seals and walruses, no humans have reported similar symptoms. However, it is not known whether the disease can be transmitted to humans or other animals. In most cases, necropsies and lab tests have revealed skin lesions, fluid in the lungs, white spots on the liver, and abnormal growths in the brain. Some of the seals and walruses have undersized lymph nodes, possibly a sign of weakened immuned systems. In Canada and Russia, ringed seals have been reported suffering similar symptoms. It is unknown whether they are related.