Hundreds of whales have died overnight on a New Zealand beach after a mass stranding thought to be the largest in decades.
A conservation department worker noticed the whales washed ashore on Thursday evening, but the government agency decided against a night rescue effort for fear volunteers would be injured by the whales in the darkness.
Local media reported on Friday that volunteers had managed to refloat some of the whales during high tide, but most were quickly restranded as the tide ebbed.
Around 300 whales beach in New Zealand every year, with the largest documented event being the stranding of over 1,000 in 1918 on the Chatham Islands.
The exact reasons for strandings are unknown and may include a myriad of factors. According to Project Jonah, mass beachings often occur when one or two whales become stranded and send out distress signals drawing in other whales who also become stranded as the tide recedes.
A necropsy of some of the whales will be undertaken by Massey University later Friday, the department said.