PARENT SESSION
Contributed Oral Session 126: Mammal Ecology: Management, Reproduction, and Food Webs
Thursday, August 11, 8:00 AM - 11:30 AM, Meeting Room 524 C, Level 5, Palais des congrès de Montréal

Potential use of river otter as species indicator for evaluating ecological integrity.

Gallant, Daniel^*,1, Vasseur, Liette^{1, 2}, Berube, Celine ³, Tremblay, Eric⁴, ¹ Universite de Moncton, Moncton, NB, Canada² Laurentian University, Sudbury, ON, Canada³ NSERC, Ottawa, ON, Canada⁴ Kouchibouguac National Park of Canada, Richibuctou, NB, Canada

ABSTRACT- The concept of using indicator species to obtain indirect information on other ecosystem components is increasingly popular. The increasing number of critical works on the subject now allows managers to select indicator species to monitor ecosystem based on justified criteria. Research on potential indicator species is currently needed to validate their use in specific contexts. Our study aimed at evaluating the potential use of river otter (Lontra canadensis) as an indicator of riparian terrestrial habitat integrity at the regional scale. We studied the influence of anthropogenic activities on otter distribution along rivers in a study area encompassing the protected areas of Kouchibouguac National Park of Canada and its vicinity which includes various anthropogenic disturbances. Habitat selection by otters was assessed by conducting riparian transects during the winters of 2003 and 2004, documenting otter activity at 500 m intervals along sampled rivers. We measured ecological, geographical, physical and anthropogenic activity factors known to be of relevance to river otter ecology. Logistic regressions indicated that otter habitat selection was correlated with several ecological characteristics associated to undisturbed habitats and negatively correlated to anthropogenic activities. We conclude that that this species can be used as a positive indicator of riparian terrestrial habitat integrity, or a negative indicator for the level of anthropogenic activity along shores. For proper ecosystem management and conservation, researchers using otter as an indicator in the same context should verify that no overriding influences (i.e., extreme water pollution) are present in the area of interest.

Key words: river otter, monitoring, indicator species, anthropogenic activities