Sydney, Feb 19 : About 90 surviving false killer whales will be euthanized after a pod of 157 became stranded on a beach in the Australian island state of Tasmania.

Authorities on Wednesday arrived at the beach on Tasmania's remote northwest coast and confirmed that 90 of the false killer whales were still alive after they were discovered by a member of the public on Tuesday evening.

Wildlife veterinarians and staff from Tasmania's Parks and Wildlife Service (PWS) and Marine Conservation Programme made several attempts to refloat two of the false killer whales on Wednesday but were unsuccessful.

PWS Incident Controller Shelley Graham told reporters on Wednesday afternoon that the animals were continually re-stranding and that conditions were forecast to be very similar for two days.

"Following expert wildlife veterinary assessments, we have made the decision to euthanize the animals," she said.

Deputy Incident Controller Kris Carlyon said that the animals would be euthanized by firearm.

He described the remote location as "possibly the trickiest" for a stranding during his 16 years in the role.

The PWS estimated that the animals had been stranded for 24-48 hours, Xinhua news agency reported.

PWS liaison officer Brendon Clark said at a press conference in the state capital of Hobart on Wednesday morning that it was the first recorded mass stranding of false killer whales in Tasmania since 1974, which involved about 160 animals.

"Horrible sight: more than 150 small killer whales washed ashore in Tasmania. This is the first time in the last 50 years that such an incident has occurred in the region, the media reports. Many of the mammals are reported to be still alive and struggling to survive. The reasons why the killer whales washed ashore are unknown," a local resident posted on social media.

/IANS