Since the beginning of the summer season here in Victoria, we have had many sightings of one of our cute and mischievous neighbors in the harbour: River Otters!
River Otters are small aquatic mammals. They eat fish, shellfish, birds and other small mammals. River Otters can stay underwater for up to 4 minutes. Their dense, oiled fur keeps them warm by keeping water out. While they have been hunted out of certain areas of North America historically, they thrive in the greater Victoria area! River Otters have less dense fur than their cousins, the Sea Otter. River Otter fur was less valued in the fur trade helping them survive the last century better than Sea Otters.
River Otters have delayed implantation, meaning after breeding season, actual gestation or “pregnancy” doesn’t occur for another 10-12 months. Once pups are born, they are helpless and blind for three weeks. They spend around six months with their mothers learning to forage and swim before becoming independent! Since most pups are born in March or April, they will be leaving their mothers around now! Check out this video of a sea otter mom and pup taken by our Naturalist Emma.
Like many animals River Otters play an important role in the ecosystem and require conservation. They are the top of the food chain and eat lots of smaller animals. Eating many small animals allows toxins to bioaccumulate in the River Otter’s body. (Think of how you’ve heard of bioaccumulation of mercury in tuna- why you shouldn’t eat it too often). Healthy River Otters can indicate a relatively clean environment. In this way River Otters are useful as biological indicators of pollution and contamination because of their place at the top of the food chain. For the Victoria Harbour pollution and contamination is a concern given the industrial history of the area. River Otters also play an important role in regulating the populations of small animals like crabs and mussels. By regulating the number of the small invertebrates, overabundance is avoided and a stable ecosystem is achieved.
Keep an eye out when you are on our docks before and after your whale watching tour, you may spot a River Otter!
Sources:
https://www.crd.bc.ca/education/our-environment/wildlife-plants/marine-species/otters
http://www.discovervancouverisland.com/wildlife-on-vancouver-island/river-otters/
http://www.env.gov.bc.ca/fw/wildlife/trapping/docs/river_otter.pdf