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The vaquita, the world’s most endangered marine mammal, has edged closer to extinction. There are no more than around 10 of the small porpoises still alive, a committee of conservation scientists concluded in a report published yesterday, down from 30 in 2017 and around 600 two decades ago.

Worse still, their number could have fallen further, as the campaign group Sea Shepherd reported yesterday that one of its vessels’ crews had found a dead animal they believed is a vaquita. The animal hasn’t yet been formally identified but a necropsy is under way and results are expected today, the group told New Scientist.

The porpoise is found only in the northern Gulf of California, where it has retreated into the southwestern corner of its refuge. The species’ decline has been driven by demand in China for the swim bladder of the totoaba fish, which fishing vessels catch with illegal gill nets, hanging curtains of netting. Vaquita can become entangled in these nets.

Despite efforts at international forums to save the porpoise, the International Committee for the Recovery of the Vaquita (CIRVA) estimated the species had declined by 50 per cent in the past three years. “This precipitous population decline has continued despite the actions taken by the government of Mexico,” according to the report by the committee, which advises Mexico on the species.
Credit : Newscientist

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False killer whales are oceanic dolphins found in deep, open waters throughout the tropics . Entirely  grey black in colour, they lack the white patches found on killer whales. False killer whales are so named because the shape of their skulls, not their external appearance, is similar to that of killer whales. Reaching up to 6 meters in length, the species behaves much more like a smaller dolphin, swimming quickly, occasionally leaping, and sometimes approaching whale watching vessels.  Killer whales are found in all oceans. While they are most abundant in colder waters like Antarctica, Norway, and Alaska, they are also found in tropical and subtropical waters. The most well-studied killer whale populations occur in the eastern North Pacific Ocean.  They eat Orcas, also known as killer whales despite being members of the same family as dolphins, are apex predators who are known to feed on nearly every species of large whale.

What do false killer whales do to dolphins? In the Eastern Pacific, the false killer whale has been known to target smaller dolphins during tuna purse-seine fishing operations; there are cases of attacks on sperm whales (Physeter macrocephalus), and one instance against a calf of a humpback whale (Megaptera novaeangliae).

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In an ancient shallow bay of what is now Montana. the body of an octopus-like creature the size of a fist was buried on the seafloor. Some 325-328 million years later, a new paper published in Nature Communications provides some interesting insights into this mysterious and ancient cephalopod.

Syllipsimopodi  bideni is small (about 12cm in length), and a triangular pen of hard tissue inside its body for support. It's a unique find because "squishy" animals tend to degrade quickly after death and therefore rarely make good fossils. We don't know when this unusual fossil was discovered, but in 1988 it was donated to the Royal Ontario Museum in Canada. It would sit largely ignored for more than 30 years until American palaeontologists Christopher Whalen and Neil Landman decided to study it.

The researchers have named the species Syllipsimopodi bideni after Joe Biden, the 46th President of the U.S. Biden had just been inaugurated when the study was submitted for publication, and the authors wanted to recognise his commitment to science

The authors suggest that Syllipsimopodi bidents features make it the oldest member of a group called the vampyropods. This is the group of cephalopods that includes modem octopuses and the "vampire squid". While octopuses will be familiar to you, the vampire squid may not. There is a single surviving species, Vampyroteuthis infernalis, whose name means "vampire squid from hell", despite being more closely related to octopuses.

Notably, the vampire "squid" has primitive features in common with this new species Syllipsimopodi bideni, such as 10 limbs and a stiff internal shell. No living octopus has either of these. Until now, it was thought that the vampyropods (octopus relatives) originated in the Triassic period around 240 million years ago. But this new species pushes that back a further 82 million years, which is more time than separates humans from Tyrannosaurus rex. PTI .

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