Listing
Dec 30, 1982
Dec 30, 1982 Listing
Review of Vertebrate Wildlife for Listing as End. or Thr. Species
- Publication type: CNOR
Item 1
FWS Focus
Overview
Characteristics
Overview
The Arctic grayling is also considered to be a salmonoid, or a member of the salmon family. They are the only salmonoid with a distinguishing sail-like dorsal and the only grayling species found in North America.
These fish inhabit open water in clear, cold, medium to large rivers and lakes. Adult Arctic grayling spawn in mountain streams in shallow water with a rock and gravel bottom and have a strong current
Fluvial, or river dwelling, Arctic grayling are still present in southwestern Montana. Unfortunately, there has been a significant decline in the range and abundance of fluvial grayling which were once widespread in the Upper Missouri River Basin above Great Falls, Montana. Currently there are only two fluvial grayling populations in Montana.
Scientific Name
Thymallus arcticus
Common Name
Arctic grayling
FWS Category
Fishes
Identification Numbers
Characteristics
Characteristic category
Physical Characteristics
Characteristics
Physical Characteristics
Migration Behavior
The Arctic grayling is a migratory fish. During the winter, these fish are found in the deep pools of river systems where the water never freezes during the winter. In late spring to early summer these fish will migrate upstream to their traditional spawning areas. Arctic grayling in Montana have been recorded swimming 60 miles in between habitats in the Big Hole River, Montana.
Weight
The heaviest published weight for Arctic grayling was 8.4 pounds.
Size & Shape
Common length for Arctic grayling is 13.5 inches with the longest reported specimen being 30 inches.
Characteristic category
Habitat
Characteristics
Habitat
Arctic grayling inhabit open water in clear, cold, medium to large rivers and lakes. Adult Arctic grayling spawn in mountain streams in shallow water with a rock and gravel bottom and have a strong current.
Characteristic category
Food
Characteristics
Food
Young grayling feed on zooplankton, with a gradual shift to immature insects as they grow older. Adult grayling feed on surface insects but also on fish, fish eggs, lemmings and planktonic crustaceans.
Characteristic category
Life Cycle
Characteristics
Reproduction
Arctic grayling begin to spawn between the ages of 3 and 4 years. In the spring, adult Arctic grayling move into tributaries and male Arctic grayling begin to establish territories before the females arrive. Adult grayling then begin to school and will eventually begin to reproduce by broadcast spawning.
In early fall, Arctic grayling will begin to slowly migrate back to overwintering areas that are normally downstream of their feeding areas.
Characteristic category
Behavior
Characteristics
Behavior
Migration Behavior
The Arctic grayling is a migratory fish. During the winter, these fish are found in the deep pools of river systems where the water never freezes during the colder months. In late spring to early summer, these fish will migrate upstream to their traditional spawning areas. Arctic grayling in Montana have been recorded swimming 60 miles in between habitats in the Big Hole River, Montana.
Geography
Characteristics
Range
Arctic grayling are native to drainages of the Arctic Ocean, Hudson Bay, Upper Mississippi and Northern Pacific Ocean in North America. Two distinct populations historically inhabited waters in Michigan and Montana. The distinct population of Arctic grayling in Michigan is now extinct although reintroduction efforts are ongoing. Fluvial, or river dwelling, Arctic grayling are still present in southwestern Montana. Unfortunately, there has been a significant decline in the range and abundance of fluvial grayling which were once widespread in the Upper Missouri River Basin above Great Falls, Montana. Currently there are only two fluvial grayling populations in Montana, in the Big Hole River, upstream from Divide, Montana and the Upper Ruby River near Alder, Montana.
Timeline
Explore the information available for this taxon's timeline. You can select an event on the timeline to view more information, or cycle through the content available in the carousel below.
32 Items