The vaquita, the world’s most endangered marine mammal, has edged a step 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 another 10 per cent, as the campaign group Sea Shepherd reported yesterday that one of its vessels’ crews had found a dead …