River Otter Latrine Site Selection in Arid Habitats of Western Colorado, USA

Abstract

River otters (Lontra canadensis) select specific habitat features when establishing latrines, but no studies have described latrine features in arid and semiarid environments. We developed a model describing those habitat features that influence otter latrine site selection on rivers in arid and semiarid watersheds of western Colorado, USA. River otters selected latrine sites with the presence of beaver (Castor canadensis) activity, large prominent rocks, adjacent to deeper water, with shading over the site, and rock or cliff overstory. Our model provides a robust predictive tool for identifying river otter latrine sites in arid environments of southwestern North America.

Density of river otters (Lontra canadensis) in relation to energy development in the Green River Basin, Wyoming

“…First, our observed site-specific habitat measurements have shown that when establishing a latrine in all river reaches, river otters selected for similar features, namely high overstory and grass cover, moderately sloping banks, and relatively deep pools. These features have been previously described as suitable for river otters in western streams and lakes (Crait and Ben-David, 2007;DePue and Ben-David, 2010). As indicated by our habitat modeling, the NF had the highest availability of overstory and grass cover at the landscape level compared with the other two reaches.…”

“…Errors using the TEV method were generally higher, but showed similar trends (Table B1). These error rates are higher than other studies in this region (Hayes et al, 2014), but adequate for quantification of habitat features important for river otters (i.e., overstory cover; Crait and Ben-David, 2007;DePue and Ben-David, 2010).…”

“…Because these crustaceans are active only during the summer months (Hubert, 2010), they are available to river otters only seasonally. River otters exhibit high fidelity to latrine sites (Bowyer et al, 2003;DePue and Ben-David, 2010), which are used over decades. When river otters are present, such long-term use is usually easy to detect.…”

Summer Diet Characteristics of North American River Otters (Lontra canadensis) in Central Illinois

“…River otters have the ability to adapt to a wide variety of habitats and their associated prey species (Melquist and Hornocker, 1983;Dubuc, 1987;Newman and Griffin, 1994;Reid et al, 1994;LeBlanc et al, 2007;Cote et al, 2008;DePue and Ben-David, 2010;Stearns and Serfass, 2011). At Emiquon, fish were the dominant prey type as they often are throughout the range of otters, but crayfish were significantly more important than was expected.…”

“…River otters are commensal with North American beavers (Castor canadensis) which provide a variety of important habitats for otters, through their environmental modification, including abundant aquatic food sources from the pooled water, stable water source, plant cover, den, and resting sites (Newman and Griffin, 1994;Dubuc, 1987;LeBlanc et al, 2007;DePue and Ben-David, 2010). The most important of these habitat features is food availability, but shelter availability limits how long an area is used (Melquist and Hornocker, 1983).…”