Cuba has introduced sweeping reforms of its fishing laws in a move seen as smoothing the way for possible collaboration with the US on protecting their shared ocean, despite Donald Trump’s policy of reversing a thaw in relations.

The move is the first time the text of an environmental law in Cuba specifies the need for scientific research, which experts say will mean greater reliance on state-of-the-art US technology.

“If we don’t look for collaboration we can’t have the full picture,” said Jorge Angulo Valdes, a Cuban marine biologist at the University of Florida. Ocean science must continue to transcend political pressures, he said. “Trump is doing everything he can to close the doors on collaboration. Cuba is doing everything to make it easier to keep those doors open.”

Cooperation is as vital to US interests as it is to Cuba, Angulo-Valdes said. The two countries are separated by just 140km (90 miles) of water, and Cuban waters provide spawning grounds for species of snapper, grouper and other commercially important reef fish in the US. Maintaining healthy numbers of bonefish, a lucrative game fish in south Florida, for example, depends on protecting the species in Cuban waters, where the bonefish spawn, said Angulo Valdes.

In December 2018 Terra satellite captured this image of the narrow, watery boundaries that separate the US, Cuba, and the Bahamas Photograph: Modis/Terra/Nasa

The reforms are Cuba’s first major overhaul of fishing laws for more than 20 years and a major step for preservation of some of the world’s most important marine ecosystems, said Dan Whittle, Caribbean director of the US-based Environment Defence Fund (EDF), which has worked with Cuba on conservation and sustainable fishing and brokered several of its key environmental agreements with the US.

“These laws also level the playing field because now the US can say that their neighbours are using the most up-to-date science,” said Whittle.

Despite having some of the world’s best preserved marine ecosystems, Cuba has seen declining fish populations, including of key commercial stocks like grouper and snapper. Angulo Valdes said: “Marine resources weren’t doing well, nearly 80% were in critical condition. The old law didn’t cover the private sector and wasn’t working.”

The new laws aim to curb illegal fishing, recover fish populations and protect small-scale fisheries, with increasing use of data-limited methods that allows fisheries to assess which species are most vulnerable, even when scientific data on specific stocks is scarce. The laws also separate sport and recreational fishing and brings fisheries under the management of the food industry ministry (Minal).

A key feature is a new licensing framework for the growing private commercial fishing sector in Cuba. Established in 2009 to increase seafood production and create jobs, this sector now has 18,000 private commercial fishers operating out of more than 160 fishing ports to provide seafood to state markets.

Then-US president Barack Obama and president of Cuba Raul Castro attend a baseball game in Havana, Cuba, in 2016. Photograph: Michael Reynolds/EPA

After former president Barack Obama normalised relations with Cuba in 2014, the countries signed landmark environmental deals and in 2017 the countries signed a pact to jointly prevent and clean up oil spills in the Gulf of Mexico, shortly before Trump took office.

Trump has tightened the US economic embargo on the Caribbean island and imposed heavy travel restrictions, after years of a boom in US travel to Cuba.

In May the Associated Press said restrictions has begun to hurt scientific cooperation and reported Patricia González, director of the University of Havana’s Centre for Marine Research, as saying that Cuban ocean scientists were being granted fewer visas to travel to the US and that some of their American counterparts were worried about travelling to Cuba in case they faced retaliation on their return home.

“[Under Trump] NGOs have continued doing ground research involving scientists from Cuba and the US but it has been slower and more under the radar,” Whittle said.

Underwater reef scene showing hard corals and schools of tropical fish in shallow water, Gardens of the Queens, Cuba. Photograph: Wildestanimal/Alamy

Cuba’s past isolation was a factor in preservation of its stunning coral reefs, including its famed Gardens of the Queen, a national park covering 850 square miles that was named by Christopher Columbus to honour Spain’s Queen Isabella I.

“Even before the new law, the country had some of the most successful conservation strategies in the world,” said Valerie Miller of the Environmental Defence Fund. “Cuba was talking about climate change years before many others and stayed ahead in conservation strategies. It has an extremely healthy coral reef with some of the world’s best biodiversity.”

Whittle said: “[The reforms] are important for the people of Cuba but are also a significant step in international efforts to preserve some of the world’s most important coral reefs, sharks, rays and other marine life.”