Date of Award

12-2018

Document Type

Thesis

College

College of Arts and Sciences

Degree Program

Biology

Degree Name

Master of Science

Thesis Advisor

Janice Chism

Committee Member

Bill Rogers

Committee Member

Kristi Westover

Keywords

River otters, Lontra canadensis, Mustelidae, Social determinants, Behavior, Captivity

Abstract

Field Studies of North American River Otters (Lontra canadensis), documented social behavior atypical among its mustelid relatives. In the wild, river otters are most active during crepuscular hours and males have been shown to be more social than females, as they cooperatively forage within bachelor groups (Blundell et al. 2002). Most social behavior occurs at latrine sites, where feces act as a means of communication between conspecifics (Blundell et al. 2005). While scientists have conducted some behavioral research on wild river otters, detailed studies of interactions are difficult for a species that ranges widely. A full understanding of river otter social patterns requires captive studies, however, as yet few such studies have been done. To help fill this gap we carried out a study of the social behavior of a group of captive river otters. We tested three hypotheses: first, that male otters would engage in more social behavior than females; second, that most social behavior among conspecifics would occur during the early evening; and third, that most social behavior would occur in the terrestrial portion of the exhibit (analogous to latrine sites). Data were collected at the Tennessee Aquarium in Chattanooga, TN, over 8 weeks in June-July 2017. An ANOVA revealed that our first hypothesis was rejected, and that there was no difference in sociality based on the sex of the animal (F=0.746, df=1,4, p=0.437). Our second hypothesis, that most social behavior among otters would occur during the early evening, was supported (ANOVA, F=5.79, df=3,20, p=0.005). Based on a Wilcoxon Signed Rank Test, our third hypothesis, that iii river otter social behavior would occur more often in terrestrial areas, was rejected (x̅ =0.418, sd=0.077). Our data suggest, in a captive setting, that river otter sociality is not dependent upon the sex of the animal. River otter sociality occurred more frequently during the early evening hours, and was exhibited more often in the aquatic portion of the exhibit.

Included in

Biology Commons

COinS