The Cultus Lake Sculpin
The Cultus Sculpin, Dwarf Coast Range Sculpin and Cultus Pygmy Sculpin are all common names for a species of fish found only in Cultus lake. Cottus aleuticus "cultus population" or Cottus sp. is currently thought to be a variant of the larger and more common Coast Range Sculpin, Cottus aleuticus, and while differing in several regards, is not currently thought to be a separate species. COSEWIC considers Cottus sp. to be a "threatened" species. Because so little is known about the Pygmy Sculpin, a more formal designation has yet to be made.
While direct research is being done on a biological and genetic level, what is known about the behavior and habitat of the Cultus Sculpin is largely derived from collected samples, inference and laboratory studies. In situ observation of the fish in it's natural environment has been very limited.
A comparison between Cottus aleuticus and Cottus sp.
The Cultus Sculpin, Dwarf Coast Range Sculpin and Cultus Pygmy Sculpin are all common names for a species of fish found only in Cultus lake. Cottus aleuticus "cultus population" or Cottus sp. is currently thought to be a variant of the larger and more common Coast Range Sculpin, Cottus aleuticus, and while differing in several regards, is not currently thought to be a separate species. COSEWIC considers Cottus sp. to be a "threatened" species. Because so little is known about the Pygmy Sculpin, a more formal designation has yet to be made.
While direct research is being done on a biological and genetic level, what is known about the behavior and habitat of the Cultus Sculpin is largely derived from collected samples, inference and laboratory studies. In situ observation of the fish in it's natural environment has been very limited.
A comparison between Cottus aleuticus and Cottus sp.
Although the current population of Cultus Sculpin appears to be within healthy limits it is considered to be a species at risk primarily due to the fact that it exists in only one location (Cultus lake). For this reason, any factor(s) that might negatively effect the populations continued viability could result in it's extinction. A similar, but genetically separate, occurring species of pygmy sculpin also exists in Lake Washington, Washington State USA. Along with the Cultus and Coast Range Sculpin, another sculpin species also resides in Cultus lake. Cottus aspers or the "Prickly Sculpin" is much larger than it's smaller relative and may in fact, be one of it's predators (along with deeper dwelling salmon and trout species). Research is being done to determine whether the Prickly Sculpin plays a causal role in the Pygmy Sculpins unusual limnetic existence [Woodruff]. The Cultus Sculpin varies from other sculpins in several ways:
- Physically, it is smaller than the Coast Range Sculpin and, as an adult, does not have markings on its fins (as the Coast Range Sculpin does) It also may appear less steam lined than it's larger relative.
- In regards to habitat, the Cultus Sculpin is thought to occupy the limnetic zone (open water) instead of the usual benthic existence of most other sculpin species. Fatty deposits under the skin and a lighter bone structure may assist in this behavior. It is not known if the Cultus Sculpin resides for any length of time benthically and this is one of the questions the CLS Project seeks to answer.
- Cultus Sculpin feeding behavior varies somewhat from the Coast Range Sculpin. Both appear to feed on bottom invertebrates when available but the Cultus Sculpin is also thought to feed on zooplankton by migrating to the lake surface at night.
- Unfortunately, little is known of the spawning activities of the Cultus Sculpin and this is another area of research for the CLS Project.
Sources:
BC Fish facts; Coastrange Sculpin and Dwarf Pygmy Sculpin
http://www.env.gov.bc.ca/wld/documents/fishfacts/sculpin.pdf
UBC Graduate Thesis
"A genetic and behavioral analysis of the distictiveness of the cultus pygmy sculpin (Cottus aleuticus) and implications for its conservation". 2010. Patricia Woodruff MSc.
BC Fish facts; Coastrange Sculpin and Dwarf Pygmy Sculpin
http://www.env.gov.bc.ca/wld/documents/fishfacts/sculpin.pdf
UBC Graduate Thesis
"A genetic and behavioral analysis of the distictiveness of the cultus pygmy sculpin (Cottus aleuticus) and implications for its conservation". 2010. Patricia Woodruff MSc.