An unusual number of dying otters were found in Southwest Alaska. The U.S. Fish and Wildlife Service launched an investigation into what was killing these seemingly healthy animals.
In late January, dead and dying sea otters washed ashore near Port Moller and Nelson Lagoon. At the time, it wasn’t clear why these otters were dying says Michelle St. Martin, the U.S. Fish & Wildlife Service biologist who investigated the event.
40 otters have been confirmed dead, but some locals have reported a number closer to two-hundred. Some of the otters were sent to Madison Wisconsin for analysis. The cause of death was determined to be an infection caused by the bacteria Streptococcus, which is also known as strep says St. Martin.
“It tends to be sort of a quick death and so all the carcasses that we received, all the animals were in good body condition.”
Strep occurs naturally and has caused otter deaths in the past, but St. Martin says not a lot is known about strep.
“We don’t really know why this bacteria or how this bacteria goes about in the ecosystem.”
Joel Garlich-Miller is also a biologist for the U.S. Fish & Wildlife Service who focuses on sea otters. He studied similar mortality events in the past at Kachemak Bay. He says one thing scientists do know is otters get strep from something in their diet, but researchers aren’t sure from what.
“The otters are eating these prey items and are getting access to it that way rather than just swimming through the water and catching this.”
Researchers aren’t sure if it’s possible for humans to get a strep infection from a dead otter. Garlich-Miller says there hasn’t been any evidence showing otters have passed the bacteria on to any other animal.
“In Katemack bay it’s been very interesting. There’s a whole bunch of marine mammals in that area. We got minke whales, humpback whales, harbor seals, sea lions. There’s all sorts of birds that have been scavenging on the otter carcasses. We haven’t really seen any sort of strep-related mortality in any other species.”
The U.S, Fish & Wildlife Service doesn’t know how the recent die-off affected the otter population near Nelson Lagoon and Port Moller. Sea otters in Southwest Alaska are considered a threatened species. Their numbers have decreased around 50 percent since the 1980s.
Currently, the U.S. Fish & Wildlife Service is preparing a survey on the area’s otter population, which will be released later this year.
Editors Note: An earlier version of this article stated it was possible for otters to transfer streptococcus to humans. This information came from a researcher who was mistaken. Officials are unsure if streptococcus can be passed on to a person. If a dead otter is found it should be reported to the U.S. Fish & Wildlife Service.