BC List Status:
Red (Candidates for- Extirpated, Endangered, or Threatened status)
As a subspecies of Longnose Dace, close scrutiny
is required to distinguish the two. Nooksack Dace
has approximately 54 scales along the lateral
line and 24 around the caudal peduncle (muscle area just before the tailfin),
compared to 67 and 31, respectively, for Longnose Dace. Juveniles of the two
forms are harder to distinguish with both having a dark line extending from
nose to tail. However adult Longnose Dace are generally an olive-green colour
interspersed with brassy or gold scales, especially on the head and ventral area.
Habitat loss and degradation from floodplain dyking, stream dredging, channelization and infilling.
Seasonal low flows in late summer often exacerbated by reduced recharge capability or disruption of groundwater from development reduce useable wetted habitat and increase temperature stress.
Degradation of habitat and infill’s riffle areas due to sediment deposition from agricultural or development runoff.
Beaver dams impound flows eliminating riffle habitat.
Restricted access to usable habitats and isolation of individual populations due to artificial barriers (culverts, diversions) that prevent or inhibit fish from traversing stream reaches. This increasing population vulnerability to extirpation.
Exposure to contaminants and pollution events from point or non-point sources.
Direct mortality or reduced fitness from episodes of extreme low oxygen (hypoxia) caused by low flows or contaminated runoff.
Enhancement of or introduction/colonization of competitive, invasive or predacious fish species (e.g. Salmon, Bass, Sunfishes, Brown Bullhead species).
Apply conservation and management objectives as set out in the “Recovery Strategy for the Nooksack Dace (Rhinichthys cataractae spp.) in Canada” and “An Assessment of Potential Critical Habitat for Nooksack Dace (Rhinichthys cataractae ssp.) and Salish Sucker (Catostomus sp.).” Assess and inventory
using methodology setout in “Guidelines for the Collection of Nooksack Dace (Rhinichthys cataractae spp.).”
This species is listed under the Federal Species at Risk Act (SARA) and is subject to protections and prohibitions under the BC Wildlife Act. Habitat for this species is also governed under other provincial and federal regulations including the Fish Protection Act and Federal Fisheries Act and potentially Regional and local municipal bylaws.