Updated

Mexican authorities will use satellite tracking, drones, three naval bases and a fleet of small patrol boats to enforce a new gillnet fishing ban in the upper Sea of Cortes in a bid to save the critically endangered vaquita marina, the world's smallest porpoise.

Environment Department official Rafael Pacchiano said Friday that the $37 million plan will go into effect later in March and will last at least two years, after which it will be evaluated.

The plan would compensate fishermen for stopping the use of gillnets, which often sweep up the tiny porpoises along with their catch.

In a statement, the World Wildlife Fund praised the measures, saying they were the most serious steps taken in the last two decades to protect the vaquita.

But the group said the ban must be well enforced and fisherman must be trained in the use of alternate nets that won't trap the vaquitas. Some fishermen will be recruited to help enforcement efforts under the plan.

There are fewer than 100 of the elusive porpoises left in the Sea of Cortez, also known as the Gulf of California, the only place on Earth where they are found.

The vaquita is threatened by gillnet fishing for totoaba, a huge, heavy fish whose swim bladder is prized by chefs in China.

There is already a protected reserve area around the mouth of the Colorado River delta, but the new proposal would greatly increase the no net-fishing area southward to encompass almost all of Baja California state's coast on the gulf.

Experts agree that capturing vaquitas to breed them in captivity isn't an option because it would not be feasible to capture or hold a sufficient number of them to develop a captive breeding program. Furthermore, with so few vaquitas spread over such a wide area, chasing down and catching them would risk killing off the few remaining individuals.