New Zealand and Australia both have been citing mass-stranding of whales since last few weeks, though the situation has become worst over the weekend as the rescuers failed to save the last surviving sperm whales in both the regions respectively, counting the death figure to 91 whales since the weekend.

The total counting of the dead whales include 24 sperm whales and two minke whales, which died in a stranding around remote Ocean Beach in Tasmania, and 65 pilot whales which died in an equally remote New Zealand location, around the tip of Farewell Spit in the South Island.

Since the news of stranding cases among the whales, Australian authorities have been trying their best to save at least the last surviving sperm whale to open water from Macquarie Harbour but unfortunately the whale died late Wednesday.

"We did everything possible to save this whale", said Ms. Liz Wren, a spokeswoman for the Tasmania Parks and Wildlife Service. She said the whale appeared to be swimming strongly before it died at about 7 pm.

Regarding the worsened situation, Mr. Anton van Helden, a marine mammal expert at New Zealand's Te Papa museum, highlighted that the most triggering factor behind mass-stranding in majority of cases is the survival strategy of a single whale in the water. He explained further that a sick whale usually seeks shallower water to recover, thus it doesn't swim so far to reach the surface and breathe, and this results in the whale becoming beached rather than recovering.

This usually sends a distress signal to other whales in the pod and they also join it as part of the group's strong social cohesion. Since the whales are highly dependent on one another to spend their life in the ocean and to deal with any such ailment, any massive havoc is easy to occur, Mr. Van Helden said.