A team of U.S. scientists and environmentalists met with Cuban officials this week to discuss a proposed alliance, including Mexico, to protect the Gulf of Mexico’s declining shark population.

The meetings were a product of both improved U.S.-Cuba relations and concern that only a joint effort by the three nations that share the gulf can protect sharks, whose numbers are said to be down as much as 50 percent for some species.

“The Gulf of Mexico is one ecosystem, it’s not just the U.S. gulf. The shark is a highly migratory fish that moves between the countries and it is troubled,” said Pamela Baker, gulf policy advisor for the New York-based Environmental Defense Fund, which is spearheading the effort along with the Mote Marine Laboratory in Sarasota, Florida.