Cottus sp.

Identification Tips:

• Large head and mouth relative to body size
• Very small adult body size (< 5 cm) • Smaller pelvic fin size compared to body size than Coast Range Sculpins

Conservation Status:

British ColumbiaCanadaNatureserve
COSEWICSpecies at Risk Act
Red ListThreatenedThreatenedG1G2, S1S2

Information Source: BC Conservation Data Centre: http://a100.gov.bc.ca/pub/eswp/

Life History:

• Feed on zooplankton (primarily Daphnia), which are very abundant in Cultus Lake relative to other lakes in British Columbia
• Preyed upon by Prickly Sculpin, Bull Trout, and likely other Salmonid species and Northern Pikeminnow
• Appear to migrate vertically in the lake, following Daphnia into mid water areas at night and into deeper water during the day.

Habitat:

• Found in mid and deep waters of Cultus Lake (area 6.3 sq. km; max. depth 42 m)
• Spawning habitat us assumed to be rocky areas in deep water as none has been observed in tributary streams to the Lake or • shallow inshore areas.

Range:

British Columbia
• Restricted to Cultus Lake in the Fraser Valley

Global
• A similar, but independently evolved, form of sculpin is found in Lake Washington.

Comments:

• Cultus Pygmy Sculpins are derived from Coastrange Sculpins (Cottus aleuticus), but are smaller and retain larval characteristics including lower bone density and higher fat content.
• These characteristics allow them to occupy mid-water habitats despite not having the gas filled swim bladder that most other (non-sculpin) species use to regulate their buoyancy.

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Primary Information Source:
McPhail, J.D. 2007. The Freshwater Fishes of British Columbia. University of Alberta Press. Edmonton, Alberta.