Aquatic Species at Risk - Speckled Dace

Speckled Dace

Speckled Dace

SARA Status: Endangered
COSEWIC Status: Endangered

Region: British Columbia

Region: British Columbia

Did You Know?

Speckled Dace are thought to be an important link in aquatic and terrestrial food chains.

Description

The Speckled Dace is a small (51 - 94mm long) river-dwelling minnow. Their elongated body is mainly grey to brownish-grey, with dark speckles, while the belly is yellowish to white. The lips, snout, and lower fin bases may be orange to red. Speckled Dace have a sucker-like mouth at the end of a prominent snout. Higher scale counts and the lack of barbels near the mouth differentiate Canadian Speckled Dace from populations in the United States.

Speckled Dace feed on filamentous algae and bottom-dwelling aquatic insects. Adults start to breed after reaching ~40mm in length, generally in their second or third year. Spawning likely occurs in July, with the number of eggs per female ranging between 400 and 2,000. It is thought that once fertilized, eggs develop into free-swimming larvae after about two weeks, with fry appearing in early August; however, little is known of the species' reproduction. Speckled Dace potentially live to the age of four years.

Habitat

Speckled Dace are only found in the western United States (where they are widely distributed) and Canada. In Canada, the Speckled Dace reaches the northern limit of its distribution, occurring in the Kettle River system (Kettle, West Kettle, and Granby Rivers) in the British Columbia Southern Interior. In British Columbia, Speckled Dace are generally found in slow flowing, shallow habitats. Immature fish are associated with small gravel or cobble substrates and slower flowing water near river margins, runs, riffles and pools. Mature fish prefer boulders or cobbles, and faster flowing, deeper water; however, little is known about deep pool habitat use. The species appears to be adaptable to a wide range of water temperatures and flow velocities.

Threats

Threats to the Speckled Dace include: water use from reduced flows in the summer and autumn due to irrigation and other consumptive uses, and inundation and loss of habitat through potential hydro development; industrial land use such as agricultural and forestry activities that increase siltation, and mining activities that can also release harmful substances; invasive piscivorous fish that can increase predation on Speckled Dace, and possibly climate change.

Further Information

Since the 2006 Committee on the Status of Endangered Wildlife in Canada assessment, multiple recovery initiatives have been carried out for Speckled Dace. A research document in support of critical habitat identification was published by the Canadian Science Advisory Secretariat, and a Simon Fraser University Master of Science thesis was published on population, distribution and diet of Speckled Dace. In addition, the Kettle River Watershed Management Plan, in development by the Province of British Columbia, will inform decisions around flow and riparian habitat management that are expected to benefit Speckled Dace.

Fisheries and Oceans Canada is currently developing a Recovery Strategy for the Speckled Dace, in cooperation with the Province of British Columbia.

The Speckled Dace is protected under the federal Species at Risk Act (SARA). More information about SARA, including how it protects individual species, is available on the SARA Registry.

To know if this species is protected by provincial or territorial laws, consult the provinces' and territories' websites.

Text Sources:

  • Fisheries and Oceans Canada. 2014. Recovery Strategy for the Speckled Dace (Rhinichthys osculus) in Canada [Draft]. Species at Risk Act Recovery Strategy Series. Fisheries and Oceans Canada, Ottawa. v + 30 pp.
     
  • COSEWIC 2006. COSEWIC assessment and update status report on the speckled dace (Rhinichthys osculus) in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. vi + 27 pp. (www.registrelep-sararegistry.gc.ca/sar/assessment/status_e.cfm).

Scientific Information

Scientific Name: Rhinichthys osculus
SARA Status: Endangered (March 2009)
COSEWIC Status: Endangered (April 2006)