Communication stations: cameras reveal river otter (Lontra canadensis) behavior and activity patterns at latrines

Abstract

Little is known about the behaviors river otters (Lontra canadensis) commonly exhibit when visiting latrine sites. By use of video data we constructed an ethogram to describe and quantify latrine behaviors. The most common behaviors were standing (20.5 %) and sniffing (18.6 %), lending support to the hypothesis that latrines are used for olfactory communication. Surprisingly, defecation was rarely observed (1.4 %); body rubbing occurred more than defecation (10.5 %). It is possible that, in addition to feces, urine, and anal jelly, river otters use body rubbing to scent mark. To monitor site use, we determined seasonal, monthly, and daily visitation rates and calculated visit duration. River otters most frequently visited the latrine in the winter (December and January) but the longest visits occurred in the fall. Very few visits were recorded during the summer. Latrines were most often visited at night, but nocturnal and diurnal visit durations were not different. River otters were more likely to visit the latrine and engage in a specific behavior rather than travel straight through the site. Our data supported the idea that river otters are primarily solitary mammals, with most latrine visits by single otters. However, we documented groups of up to 4 individuals using the area, and group visits lasted longer than solitary visits. Therefore, whether visits are solitary or social, latrine sites are likely to act as communication stations to transmit information between individuals.