A new report from the US Geological Survey (USGS) revealed that the populations of California sea otters have reached the highest level since 1982.

The USGS report, released on Sept. 19, showed that the number of sea otters living along the California coast have grown to 3, 272 this year, an 11 percent increase since 2013. For the first time, the number of California sea otters has exceeded 3,090. If the population remains more than 3,090 for two more years, California sea otters will be removed from the endangered species list and will be reclassified as "threatened."

"The population is slowly but steadily recovering," said Tim Tinker, a research biologist in Santa Cruz who leads the USGS' otter program, in a report from Mercury Times. "And that's good news because sea otters bring ecological benefits."

The California sea otters' range spans the coast of Monterey to Cambria. A significant increase in the population was observed in the central part of the range. Scientists believe that one of the contributing factors in the increase of California sea otters is the abundance of sea urchins throughout northern and central California.

However, localized population of sea otters in the northern and southern edge of the range are declining, raising concern among resource management officials. Experts believe that the decline of sea otter population in these areas, especially in the northern part, are due to shark attacks.

California sea otters, or southern sea otters, are considered to be keystone species, which means that their role in their environment has a greater effect than other species.

With a historic population of about 16,000, the California sea otters were hunted close to extinction for their pelts. Sea otters have the densest fur in the animal kingdom that ranges from 250,000 to a million hairs per square inch to make their bodies warm.