Under the plans, trawlers would avoid stretches of ocean when endangered species are mating, spawning or passing through

Some of the world's most endangered marine life could be saved from extinction by establishing mobile nature reserves that would protect vulnerable species as they moved around the oceans, scientists say.

The initiative could provide safe havens for endangered loggerhead and leatherback turtles, albatrosses, sharks and other travelling species, and sea life that is abandoning its historic territories in response to climate change.

Under the proposals, trawlers would agree to avoid certain stretches of the sea at set times of the year when endangered species are mating, spawning or passing through. Those ocean regions might move with the seasons, ocean currents and long-term environmental events like El Niño, the researchers said.

Mobile marine reserves could bolster existing protected areas that draw an invisible cordon around fixed regions of the oceans, such as coral reefs and sea mounts, where ecological diversity is linked to geographical features.

Instead of restricting areas by their location, mobile reserves would identify particular conditions that attract marine life "The stationary reserves do little to protect highly mobile animals, like most of the fish, turtles, sharks and seabirds," said Larry Crowder, science director at the Centre for Ocean Solutions at Stanford University. "We think of protected areas as places that are locked down on a map. But places in oceans are not locked down, they move."

The idea was proposed at the annual meeting of the American Association for the Advancement of Science in Vancouver.

One potential mobile marine reserve could protect the north Pacific convergence zone, a region where two giant currents meet head-on, bringing plankton, small fish, turtles and major predators together. The zone is always teeming with life, but it moves from season to season.

"In the summer, it's 1,000 miles [1,800 kilometres] further north than in the winter, so if you were going to protect something there, it makes no sense to protect that latitude, because it moves," said Crowder.

Similarly, as the oceans warm, some marine species are shifting their territories to find more comfortable habitats. Marine reserves will be no benefit if they do not track the species as they move, Crowder said.

Hopes of creating mobile marine reserves have been around for more than a decade, but Crowder said that only in recent years has the concept become plausible because of improvements in satellite imaging and GPS tagging of species. With these technologies, marine biologists have learned in great detail the movements of different sea creatures.

Another area of interest to conservationists is known as the white shark cafe, a patch of water 2,000km off the Californian coast that is teeming with sharks and is probably a mating ground. Environmental changes may see the meeting spot drift in future years, but a mobile reserve would move with them.

The new reserves could work in favour of fisheries by opening areas of the ocean that might otherwise be restricted. Modern trawlers are fitted with GPS equipment and could have maps updated each year or season to make clear which areas were off limits to protect vulnerable species.

The initiative would not prevent unlawful fishing, but would help trawlers that were trying to work the oceans without pushing species to the brink of extinction.

"People might say the only way to achieve conservation for some marine life is to protect it everywhere in the ocean. But if we know where they move to, we don't need to close the entire Pacific Ocean, we just need to close this place where they are really concentrated," Crowder said.

"The time is right for this idea. We are scientifically primed to do it."