This undated handout picture released on March 19, 2017 by the US environmental group Sea Shepherd Conservation Society shows a dead newborn "vaquita marina" porpoise found at Playa Hermosa beach in the Gulf of California, Mexico

Mexico announced plans Friday to use trained dolphins to corral the last remaining vaquita marina porpoises into a protected breeding ground, a last-ditch bid to save the critically endangered species.

Scientists estimate there are just 30 remaining vaquitas, the world's smallest porpoise, a found only in the waters of the Gulf of California.

Environment Minister Rafael Pacchiano said the authorities would deploy dolphins trained by the US Navy to herd as many vaquitas as possible into a marine refuge.

He admitted the project, due to start in September, would be difficult.

"We've spent the past year working alongside the US Navy with a group of they had trained to search for missing SCUBA divers. We've been training them to locate the vaquitas," he said in an interview with radio network Formula.

"We have to guarantee we capture the largest possible number of vaquitas to have an opportunity to save them."

The government also announced Friday it has permanently banned the in which vaquitas are often killed.

The nets, known as gillnets, are used to catch another species, the totoaba fish, whose swim bladder is considered a delicacy in China and can fetch $20,000 per kilogram.

The World Wildlife Fund (WWF), which has warned the vaquita risks going extinct by next year, praised the move.

The latest measures come after Mexican President Enrique Pena Nieto signed a deal on June 7 with Hollywood star Leonardo DiCaprio and Mexican billionaire Carlos Slim to increase efforts to save the vaquita.

DiCaprio had taken Pena Nieto to task on social media for not doing enough to save the species.

But the two later buried the hatchet.

The Hollywood heartthrob welcomed the permanent gillnet ban as "great news" on Twitter.