River Otters Disappearance Resolved

by, Skylar Silvera

River Otters have been making a strong comeback into Marin and the Bay area after almost two years of them reportedly gone missing. This reappearance of the river otters is not just beneficial for the species but a beneficial to our environment. I got a chance to interview Megan Isadore who is a naturalist, wildlife rehabilitator and a writer who first became interested in River Otters when she spied them in Lagunitas Creek. She was working on the Lagunitas watershed in service to the critically endangered coho salmon and saw the inquisitive creatures crowding around a bank. She was hooked.

Since then Megan has dedicated her life to the species and works to answer questions about the species. Little is known about the river otters general ecology, diet, status, reproduction or diet but Megan Isadore is determined to find out. Megan is working on finding the answers to these questions by hiding cameras positioned along a 100-mile stretch of coastline and streams at 11 study locations north of the Golden Gate.

These cameras document the occurrence of the species as well as social aspect of the otters life. I learned from her videos  that males can be extremely territorial but not violent towards other male others, and that the female otters tend to be more isolated so that they can properly care for their young. The female otters are excellent mothers and actually carry their eggs inside their womb for up to two months which I found very interesting. They also gather otter droppings and “jelly” which is an intestinal secretion that Megan can use for genetic analysis  that could be used to discover population numbers, sex ratios, family ratios and otter ranges.

After Megan discovered the otters in the Lagunitas Creek, they started appearing in other locations such as in Corte Madera. They could be seen lounging in the Corte Madera Creek or the lagoon. They have also turned up on docks in the San Rafael Canal and along the county's West Marin coast.The otters come up from the bay and spend time in the canal and manage to find peaceful areas around Marin county to breed and hunt for food such as shellfish, crabs, crayfish even the occasional seagull!

During her presentation of the River Otters I was both amazed and stunned by the beautiful creatures and their livelihood.  Megan Isadore started the River Otter Ecology Project in 2012. Her first order of business was to create a website where “Otter Spotters” could chart their sightings on  an interactive map. I asked her what the point of the interactive map was and she said that she has discovered so many new homes to otters all around Marin that she can use to peacefully study and research the animals without disturbing their livelihood. The map is not only a tool used to track sightings of the river otters, but also a way to determine whether the population of river otters is thriving and growing or increasing like it was a couple of years ago.

During her powerpoint presentation of the river otters and how they benefit to the environment by supporting our watersheds, I wondered if the river otters could cause anything not beneficial to the watersheds, such as bringing the population of fish down. She responded that otters tend to not go for the big salmon such as the endangered coho salmon in Lagunitas Creek, they tend to hunt for the smaller fish and often the crabs that are easier to hunt and bring back as food for their babies. There is no reported drop in species for any key fish and yet Megan has come to a conclusion that the river otter population is indeed growing day by day.

I also wanted to know how the river otters were dealing with our current drought, and she replied by saying that the number of otters is still growing but she assumes that its much more difficult for the otters to find homes on the banks of streams so the females tend to travel more inland so they can raise their babies. Other than that she reports that everyone is a victim of the drought including herself, it truly is tragic.

As my final question I asked Megan how she was spreading the word about her work to protect the otter population. She told me that she continues to gather more volunteers every week to help her research the animals and her project is posted on Facebook and Twitter. There she posts her process regularly in hopes that others will be inspired of the work being done by her and the volunteers. You can learn more about the project the Otter Project by going to their website www.riverotterecology.org.