Arctic Grayling
(Thymallus arcticus)
Arctic Grayling
Fluvial arctic grayling are
restricted to the Big Hole
River of southwest Montana.
Arctic grayling are also
found in a few natural lakes
and reservoirs in western Montana. Cold
water and gravelly substrate are needed for
breeding purposes. Conservation concerns
include: low fl ows during drought, decreasing
survival due to high water temperatures,
susceptibility to predation, and diminished
habitat volume; displacement by nonnative
trout; degradation
of riparian vegetation and
stream banks by range
or forest management
practices; and dewatering
the river for agricultural uses. Conservation
strategies include: creating riparian
rehabilitation projects for identifi ed degraded
habitats on the Big Hole River; reducing
stocking of non-native fi sh; and supporting
management of grazing to maintain riparian
vegetation and channel stability.
