Although sea otters are an unofficial mascot of the Monterey Bay area and popular among tourists and locals alike, they are also described by scientists as voracious predators that help keep problematic invaders out of coastal waters. A recent study was published in the scientific journal Biological Invasions, detailing that otters at the Elkhorn Slough are keeping populations of globally invasive green crab at bay. … Green crabs were first found at the slough in 1994 and the population peaked in the early 2000s. Since then, the population has declined and hasn’t reached the peak numbers again. Meanwhile, the population of sea otters has risen. Sea otters were recovering from near extinction in California in the early 2000s. The new study is first-time evidence that the recovery of the otters is benefitting the overpopulation of invasive species.