Depths of despair: 30 large whales found dead off Alaska, puzzling scientists

Thirty large whales have recently been found dead along the Alaskan coast, prompting a federal agency to declare an “unusual mortality event” and mount an official investigation into the mystery of what could be killing so many marine mammals.

Scientists from the National Oceanic and Atmospheric Administration (Noaa) are “very concerned” about how many whales are being found dead near and on Alaskan beaches, the agency’s Dr Teri Rowles said in a statement .

“While we do not yet know the cause of these strandings, our investigations will give us important information on the health of whales and the ecosystems where they live,” she said, asking for help from the public to report dead or distressed animals.

Since the beginning of May, 11 fin whales, 14 humpbacks, one gray whale and four unidentified cetaceans have been found dead on islands of the western gulf of Alaska and along the peninsula’s southern shore. Most died in the Kodiak archipelago.

The 30 deaths amount to almost three times the historical average, according to Noaa. There may be more unreported animals - most of the carcasses have been spotted floating and beyond retrieval and others have been scavenged by bears or decomposed past the point of recognition. Scientists have only been able to test one whale sample so far, according to Noaa.

Six large whales have also stranded in the waters of British Columbia, Canada - a fin whale struck by a ship, a sperm whale and four humpbacks. Canadian authorities have managed to take samples from two.