In a groundbreaking study published today in Nature, scientists reveal that the return of sea otters to their former habitat in a Central California estuary has slowed erosion of the area's creekbanks and marsh edges on average by 69%.
The resurgence of these charismatic marine mammals — also some of the habitat's top predators — to the saltmarsh-dominated Elkhorn Slough in Monterey County sparks hope in those dedicated to improving the health of our coastal ecosystems and marks a significant ecological success story.
"This is a solutions-oriented paper that tells us there are manageable actions we can take to produce positive results," said Christine Angelini, Ph.D., one of the study's authors and director of the Center for Coastal Solutions at the University of Florida. "In this instance, restoring the otter population was achievable without significant effort, and as a result, we are now unlocking several decades of benefits from that one act of conservation."
Findings show that the erosion of creekbanks and marsh edges in areas with large otter populations has slowed, mainly because of the sea otters' insatiable appetite for plant-eating marsh crabs and at a time when rising sea levels, elevated nutrients, and stronger tidal currents should be causing the opposite effect.
"It would cost tens of millions of dollars for humans to rebuild these creekbanks and restore these marshes. The sea otters are stabilizing them for free in exchange for an all-you-can-eat crab feast," said senior author Brian Silliman, Ph.D., Rachel Carson Distinguished Professor of Marine Conservation Biology at Duke University's Nicholas School of the Environment.
