Dolly Varden

Western Arctic population

Salvelinus malma malma
NWT SARC Assessment
Not Applicable
NWT List of Species at Risk
Not Applicable
COSEWIC Assessment
Special Concern
Federal Species at Risk Act list
Special Concern
NWT General Status Rank
Sensitive

Dolly Varden are a type of char with large eyes below the top of a round, medium-sized head, The base of their tail is long and wide, and their tail fin is flat and broad. The tail fin is unforked, a trait that helps distinguish Dolly Varden from other fish species. Juveniles are brown coloured with a whitish belly, small round red spots, and 8 to 12 rectangular marks on their sides and back. Adults have small, pale pink or red spots, with surrounding bluish halos. Spawning sea-run males are brightly coloured and develop a hook on the lower jaw, while females, non-spawners and freshwater males are more muted in colour.

This fish’s name comes from a character in a novel by Charles Dickens, Dolly Varden, who wore brightly coloured dresses. A popular fabric pattern with red polka dots was named after her in the 1800s. The fabric in turn inspired the name of the fish, because the Dolly Varden’s pink spots reminded people of the colourful cloth. 

Length: Anadromous forms, over 35 cm (13.8 in); Freshwater adults 30 cm (11.8 in) or less

Report Dolly Varden sightings to WildlifeObs@gov.nt.ca

In North America, the Western Arctic Population of Dolly Varden ranges from Alaska, east along the North Slope of the Yukon Territory, and east to the Mackenzie River. 

Dolly Varden and Bull Trout both occur together in the Gayna River, NWT. Hybridization between these two species has been recorded, but hybrids are generally not as successful as either parent species in the natural environment.

Range map information

Dolly Varden individuals may be anadromous (use both sea water and freshwater during their life) or live in freshwater only. Anadromous Dolly Varden migrate to the sea to feed for the summer, then return to freshwater in September and October to spawn and overwinter.

Anadromous and freshwater forms of Dolly Varden spawn and overwinter in freshwater springs where sufficient oxygen and suitable temperature levels provide high quality habitat for survival and egg incubation. Gwich’in knowledge indicates that spawning habitat requires relatively warm water, a fast current or high gradient, and plenty of shoreline cover and vegetation with abundant insect larvae available for food.

Cross-breeding between different life forms of Dolly Varden is not uncommon. Some freshwater males live alongside anadromous fish in the fall and winter and reproduce by “sneaking” into redds (egg laying sites) to spawn with anadromous females. This strategy is called “sneak-spawning”.

Population size is largely unknown, but Indigenous knowledge suggests declines in some populations.

Drier and warmer conditions due to climate change could lead to lower water levels and reduced groundwater flows, reducing the amount of suitable freshwater habitat, especially for spawning and overwintering.  

Industrial infrastructure projects and resource extraction can degrade habitat in ocean and freshwater environments.

Other threats include diseases and pathogens, introduced and invasive species, and over-harvesting.
 

COSEWIC assessed Dolly Varden (Western Arctic population) as a species of Special Concern in 2010. It was listed as Special Concern under the federal Species at Risk Act in 2017.

Area
Gwich'in Inuvialuit Sahtú