Researchers believe sea otters may be key to saving coastlines from growing threat: ‘This could be a very effective and affordable new tool’

An adorable assistant has helped to stop California’s coastline from eroding.

Sea otters have been recolonizing the Elkhorn Slough coastal estuary in central California, and the impact of the water-based mammals is telling.

According to SciTechDaily, areas featuring large otter populations have seen the erosion of creek banks and marsh edges slow by up to 90%, despite rising sea levels and increasingly strong tidal currents as a result of global heating.

With such impressive results, the possibility of bringing or reintroducing similar predators to coastal areas is now a focus for scientists and conservationists.

“The return of the sea otters didn’t reverse the losses, but it did slow them to a point that these systems could restabilize despite all the other pressures they are subject to,” Brent Hughes, associate professor of biology at Sonoma State University, told SciTechDaily. “That suggests this could be a very effective and affordable new tool for our conservation toolkit.”

Sea otters once thrived in the Elkhorn Lough estuary, but the population severely decreased because they were hunted for fur, had their habitats affected by local agriculture, and their survival was put at risk by human activities like construction.

With that, the population of marsh crabs, the sea otter’s preferred food source, increased dramatically. The crabs are among the main reasons for coastal erosion, as they eat salt marsh roots and dig the soil. However, a healthier sea otter population has been reducing the crabs’ numbers and improving the ecosystem, with the mammals unable to get enough of their favorite snack.

“After a few decades, in areas the sea otters had recolonized, salt marshes and creekbanks were becoming more stable again, despite rising sea levels, increased water flow from inland sources, and greater pollution,” Hughes added.

While the sea otters are no doubt delighted to help cut the number of problematic crabs destroying the marshes, they have been delighting local conservationists, too, thanks to their work and the money they are saving.

“It would cost millions of dollars for humans to rebuild these creekbanks and restore these marshes,” Brian Silliman, director of Duke RESTORE and Duke Wetland and Coasts Center told SciTechDaily. “It begs the question: In how many other ecosystems worldwide could the reintroduction of a former top predator yield similar benefits?”

Join our free newsletter for cool news and cool tips that make it easy to help yourself while helping the planet.