Hecatombs in New Zealand: 500 whales died from mass stranding



by LORENZO CIOTTI

Hecatombs in New Zealand: 500 whales died from mass stranding

Nearly 500 Long-finned pilot whales have died from mass stranding in New Zealand. The cetacean massacre took place on the remote beaches of the Chatham Islands, an archipelago made up of two islands located a thousand kilometers southeast of the North Island and the South Island.

Only twenty days ago another 200 pilot whales they had beached on Ocean Beach in Tasmania. Not all pilot whales had died when rescuers arrived: the surviving ones were however killed by veterinarians. Only 600 people live on these islands and there are not all the equipment and personnel for a quick and effective rescue mission.

"We do not actively refloat whales on the Chatham Islands due to the risk of shark attack to humans and the whales themselves, so euthanasia was the kindest option," said Dave Lundquist, a technical marine advisor for the conservation department.

About Long-finned pilot whales

The dives it makes to feed itself, or rather to look for food, can last up to 10 minutes. Its breath exceeds one meter in height. They can also be observed at a depth of 600 meters, but usually its dives go to a few tens of meters.

It feeds mainly on cephalopods. Sometimes groups are observed practically stationary on the surface, so as to allow the boats to get closer. Spyhopping, lobtailing and even breaching are often observed but this is almost only in the younger specimens.

Episodes of collective stranding have been observed, including very important ones that occurred in New Zealand in 1918 (about 1000 pilot whales) and in 2017 (at least 600 pilot whales), and on the island of Tasmania (over 200 pilot whales).

The pilot whale has a massive body with two long crescent-shaped pectoral fins. The globular head has a protruding forehead and ends with a very short rostrum. The skin is black, whitish in an area between the chest and belly.

Its maximum dimensions reach 8.7 meters in length. They are among the most common and widely distributed marine mammals of the order of cetaceans. The largest group is found in a circumpolar belt in the Southern Ocean that is approximately 20 ° S to 65 ° S.

It can be seen off the coasts of Chile, Argentina, South Africa, Australia and New Zealand. The population of this group is estimated to be over 200,000 individuals. The second population is much smaller and inhabits the North Atlantic Ocean, ranging from South Carolina in the United States to the Azores and Morocco in the south and from Newfoundland and Greenland to Iceland and northern Norway in the north.

It is also present in the western half of the Mediterranean Sea. There are 150,000 individuals in the tropical eastern Pacific Ocean. In the western Pacific it is estimated that more than 30,000 animals live off the coast of Japan.