River Otters

Observations of River Otters in the Columbia Valley have been increasing. The one pictured here was seen swimming in open water of the Columbia River

Otters rely upon the presence of clean, unpolluted water for their food, primarily fish. The ones in the Columbia Valley feed mainly on Northern Pikeminnows (Squawfish) and in the fall eat spawning Kokanee Salmon. South of Toby Creek you can often see the shell remains from where otters have eaten freshwater mollusks.

Because otters are high in the food chain, they are particularly susceptible to the accumulation of organic compounds and heavy metals. This makes them good indicators of contaminant levels in the aquatic environments. So it is a good sign that River Otter numbers are increasing in the upper Columbia Valley.

由使用者 larryhalverson 在 2020年01月16日 05:58 所貼文