Determination of Tidal Influence on Lontra Canadensis through Remote Monitoring

Presentation Abstract

Lontra canadensis, more commonly known as the North American river otter, is a resident in many riparian and coastal ecosystems across the continent. The behaviors of mainland populations – the inhabitants of freshwater lakes and rivers – have been well documented and studied over the years. The impact of tides on coastal and estuarine populations, however, is still largely unknown. Therefore in 2012, members of the Ocean Research College Academy, a dual enrollment program run through Everett Community College, began analyzing scats collected from latrine sites in Possession Sound. Preliminary diet analysis revealed target prey consisting of mostly saltwater species. Given otters’ high metabolic rates and prey availability in estuaries being driven by tidal cycles, it was then hypothesized that otters follow their marine food sources into the estuary with the high tides, when the water’s salinity would be high enough to sustain their prey species. To test this, game cameras were installed at latrine sites on Jetty Island and the Hat Island ferry dock in Everett, Washington. Visits by otters were documented and time stamped, with corresponding tide stages and heights recorded. The majority of visitations occurred at tide heights between 4 and 10 feet (72.1% of visits) with considerably fewer camera captures during extreme highs and lows.

Session Title

Session S-04D: Marine Birds and Mammals of the Salish Sea: Identifying Patterns and Causes of Change - I

Conference Track

Species and Food Webs

Conference Name

Salish Sea Ecosystem Conference (2014 : Seattle, Wash.)

Document Type

Event

Start Date

1-5-2014 5:00 PM

End Date

1-5-2014 6:30 PM

Location

Room 6C

Genre/Form

conference proceedings; presentations (communicative events)

Contributing Repository

Digital content made available by University Archives, Heritage Resources, Western Libraries, Western Washington University.

Subjects – Topical (LCSH)

North American river otter--Monitoring--Washington (State)--Possession Sound; Tides--Washington (State)--Possession Sound

Geographic Coverage

Salish Sea (B.C. and Wash.); Possession Sound (Wash.)

Rights

This resource is displayed for educational purposes only and may be subject to U.S. and international copyright laws. For more information about rights or obtaining copies of this resource, please contact University Archives, Heritage Resources, Western Libraries, Western Washington University, Bellingham, WA 98225-9103, USA (360-650-7534; heritage.resources@wwu.edu) and refer to the collection name and identifier. Any materials cited must be attributed to the Salish Sea Ecosystem Conference Records, University Archives, Heritage Resources, Western Libraries, Western Washington University.

Type

Text

Language

English

Format

application/pdf

This document is currently not available here.

Share

COinS
 
May 1st, 5:00 PM May 1st, 6:30 PM

Determination of Tidal Influence on Lontra Canadensis through Remote Monitoring

Room 6C

Lontra canadensis, more commonly known as the North American river otter, is a resident in many riparian and coastal ecosystems across the continent. The behaviors of mainland populations – the inhabitants of freshwater lakes and rivers – have been well documented and studied over the years. The impact of tides on coastal and estuarine populations, however, is still largely unknown. Therefore in 2012, members of the Ocean Research College Academy, a dual enrollment program run through Everett Community College, began analyzing scats collected from latrine sites in Possession Sound. Preliminary diet analysis revealed target prey consisting of mostly saltwater species. Given otters’ high metabolic rates and prey availability in estuaries being driven by tidal cycles, it was then hypothesized that otters follow their marine food sources into the estuary with the high tides, when the water’s salinity would be high enough to sustain their prey species. To test this, game cameras were installed at latrine sites on Jetty Island and the Hat Island ferry dock in Everett, Washington. Visits by otters were documented and time stamped, with corresponding tide stages and heights recorded. The majority of visitations occurred at tide heights between 4 and 10 feet (72.1% of visits) with considerably fewer camera captures during extreme highs and lows.