River otter demography study: a citizen science project

Otter Data Entry »

RIVER OTTER NETWORK: We are interested in describing the distribution and demography of otters on the coasts, wetlands and watersheds in Humboldt, Del Norte and adjacent counties. The river otter (Lontra canadensis) is a key bio-indicator of the health of our environment as they sit at the top of this water-based food chain. Unlike most otter habitats around the world, it is thought that the Pacific north coast still supports a thriving otter population. The initial goals of the study are:

• Establish a network of otter observers among wildlife agencies, and enthusiasts
• Assess spatial and temporal variation in otter distribution
• Assess spatial and temporal variation in pup production
• Conduct observational studies on otter foraging
• Conduct diet assessments
• Assess home range and site faithfulness of individuals

With a bit of persistence keen Humboldt student observers may enjoy hours of first hand experience watching otters and detecting signs of their activities. You can join the River Otter Network of observers. There are at least six otter groups living in habitats just a short drive from campus. You may even observe our river otters in lagoons, bays and harbors; true sea otters do not occur in this region. Wildlife Techniques (WLDF 311) students are encouraged to search for otters and to enter sightings via the Otter Records page.

River Otters: Keeping Up with Mom

Highlights  

• Flyer 1   
• Flyer 2   
• Flyer 3

Rose T, Vickers WE, Cardenas SA, Black JM 2023. North American River Otter diet includes invasive Sacramento Pikeminnow and herpetofauna on South Fork Eel River, Northern California. Northwestern Naturalist 104:229-241.

Chin A & Black JM 2020. Behavior of the Northern River Otters in relation to social group size and pup presence: results from 15 years of Citizen Science. Northwestern Naturalist 101:158–167.

Black JM, Wampole E & Mayer J 2016. Fifteen years of river otter monitoring by citizen science volunteers in northern California: Litter size. Northwestern Naturalist 97:226-236.

Brzeski K, Szykman Gunther M & Black JM 2013. Evaluating river otter demography using non-invasive genetic methods. Journal of Wildlife Management 77, 1523-1531.

Black JM 2009. River otter monitoring by citizen science volunteers in northern California: social groups and litter size. Northwestern Naturalist 90, 130-135.

Oldham AR & Black JM 2009. Experimental tests of latrine use and communication by river otters. Northwestern Naturalist 90, 207-211.

Penland T & Black JM 2009. Seasonal variation in river otter diet in coastal northern California. Northwestern Naturalist 90, 233-237.

Additional Otter Pages

• Otters.net - Check out Scott Shannon’s pages about river otters at Trinidad Harbor.
• Otter Track and Scat Website