Humboldt State University

Jeff Black, PhD, DSc

707 826 3439

River otter demography study: a citizen science project

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Photos by Talia Rose

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 HSU 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.

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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.

Links to other otter pages

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