The beaches of distant islands were covered with the carcasses of elephant seals

According to the researchers, the beaches of the islands were covered with the carcasses of southern elephant seals, when the researchers arrived on the islands in October 2025. According to the land and air counts made at that time and in January 2026, 13,300 pup carcasses were found.

Research showed that baby elephant seals had died from H5 type bird flu.

Researchers according to the bird flu had also killed other seal species as well as penguins and other birds, but elephant seals suffered the worst. In some elephant seal harems dominated by one male, the mortality of the young was up to 97 percent, according to the researchers.

The barren and uninhabited Heard and McDonald Islands are located in the Southern Ocean about 4,000 kilometers southwest of Australia. The subantarctic island group is partially covered by a glacier.

Southern elephants live in the regions surrounding Antarctica. It was previously estimated that there were about 650,000 individuals living, but in recent years bird flu has killed a significant part of the southern elephants on the island of South Georgia in the South Atlantic, for example.

Elephant seals are the largest seals. The male Southern elephant can grow almost six meters long and weigh up to 3,700 kilograms.

Bird flu has gradually spread more widely on the islands surrounding Antarctica. Researchers believe that the bird flu spread to the Heard and McDonald Islands from about 1,500 kilometers away from the Crozet Islands with an infected animal.