HAVANA, Cuba — The sharks, sea turtles and other miscellaneous underwater creatures that roam the Gulf of Mexico could care less about the U.S. trade embargo against Cuba, or the island's one-party communist state. So why should such terrestrial concerns get in the way of marine research?

That appears to be the logic behind a growing partnership between scientists in the U.S., Cuba, and Mexico working on a multinational plan to protect the gulf's underwater ecosystems. This week, a delegation of about 30 U.S. researchers and ocean advocates have been in Havana for meetings with their Cuban and Mexican counterparts, and trip organizers said they're aiming to create a regional protection strategy that all three countries would enforce.

Similar collaborations exist between the U.S. and Cuba for hurricane tracking and research, but participants said this was the most significant marine science partnership between the countries to date.

The effort is another small but significant example of improving ties between the U.S. and Cuba on matters of mutual concern — in this case a single, shared marine ecosystem. "We know our countries have different administrations and points of view, but there's only one atmosphere and one ocean," said Alberto Vazquez de la Cerda, an oceanographer and retired vice admiral of the Mexican Navy, who hosted two previous meetings for U.S. and Cuba scientists in Mexico.

"Mother nature doesn't care about borders or politics," he said.

The meetings have identified several priorities for the three countries, including research and conservation of coral reefs, sharks, sea turtles and dolphins, as well as the better management of fisheries.

Unlike other parts of the globe where large stretches of open international waters can make enforcement difficult, the Gulf of Mexico is divided almost entirely among the three countries, improving the chances for protection, scientists said.

Politics remain an obstacle to the partnership. Cuban authorities have traditionally been wary of U.S. scientists seeking to visit remote areas of the island for research purposes out of concern over espionage. And the U.S. government has routinely denied visas for Cuban marine researchers seeking to travel to the U.S., though the Obama administration has shown more flexibility lately in granting academic and research visas, according to conference participants.

"Because of the political relationship between our countries, it takes some stamina to work here," said David Guggenheim, the marine scientist who led the U.S. delegation, speaking at Cuba's National Aquarium in Havana, where the meetings were held.

A comprehensive effort to study marine ecosystems in the gulf and advocate for their protection is likely to cost tens of millions of dollars, Guggenheim said. "Eventually this is going to require the support of governments, and multiple government agencies."

One factor potentially complicating such a partnership is that Cuba is looking to develop deep water petroleum reserves in its portion of the gulf, having signed exploration deals with nearly a dozen foreign oil companies in recent years. The U.S. Geological Survey has estimated Cuba's potential oil deposits at 5 billion barrels — on par with some of the region's biggest suppliers — while Cuban officials claim up to 20 billion barrels lie beneath the ocean floor.

No offshore drilling operations are currently underway, but if Cuba and its partners do strike oil, it would present a serious new environmental hazard for the region. Prevailing currents would likely push an oil spill into the Florida Keys and up the U.S. eastern seaboard, scientists say, but they recognize Cuba is too pressed for cash to forgo lucrative energy development in favor of strict environmental protection. That's a reason U.S. scientists say they want to form partnerships now — to advocate for the safest and most sensitive drilling practices.

American scientists also said they're eager to explore Cuba's marine ecosystems, which include some of the region's most extensive and intact coral reefs. Cuba has excellent scientists, U.S. researchers said, but the country has lacked the financial resources to gather much data in recent years.

"Cuba is the least known corner of the Gulf of Mexico," said Guggenheim, director of the Washington-based advocacy group 1planet1ocean.org.

"For marine researchers in Flordia, Cuba is a very romantic place," said Robert Hueter, director of the Center for Shark Research at MOTE Marine Laboratory in Sarasota. "We've often looked south to Cuba from the shores of the Florida Keys and thought 'why can't we go there to extend our studies?'"

Hueter said the species he studies travel back and forth between the U.S. and Cuba, and that shark populations in the region have declined 50 to 75 percent since industrial fishing for the animals began 30 years ago. For some species, the decline is more than 90 percent.

That underlines the need for multinational protection, said Hueter. While he recognizes there are political reasons that make closer cooperation difficult, "from a scientific basis, it just doesn't make sense for us to treat this area of the ocean as if it doesn't exist."