Only 10 of the vaquita porpoises are left. They are being driven to extinction by gillnet fishing:

the Guardian

Extinction alert issued over critically endangered vaquita

World’s tiniest marine mammal – found only in the Gulf of California in Mexico – has only 10 individuals left, study finds

I am surprised that people did not years ago capture some vaquitas to establish a protected population. That is the usual way of saving a species when its population drops so low.