Species-at-risk

Various threespine stickleback populations in British Columbia are threatened or endangered. The limnetic-benthic species pair in Hadley Lake, Lasqueti Island, is now extinct. The limnetic-benthic species pair in Enos Lake, Vancouver Island, has collapsed to a hybrid swarm (photo of Enos benthic male above, courtesy of Ernie Cooper). Both extinctions were associated with invasive species. Remaining species pairs appear to be healthy but require protection and regular monitoring. A new species pair was discovered in 2007 in Little Quarry Lake, Nelson Island and is becoming listed at SARA.


Status under SARA

Enos Lake species pair: Endangered
Hadley Lake species pair: Extinct
Little Quarry Lake species pair: pending
Paxton Lake species pair: Endangered
Vananda Creek species pair: Endangered

The latest information on status can be found on the stickleback page at the SARA Registry


Population size estimates

Schluter, D., M. Roesti & T. Veen. 2017. Mark-recapture estimates of stickleback population sizes in Paxton and Priest Lakes in 2016. v5.1. Unpublished document.
Preprint | *Supplement
*Includes recalculation of 2005 population estimates in Paxton Lake by M. Nomura.


COSEWIC Summaries

Enos Lake species pair. 2012 assessment: Endangered

Hadley Lake species pair. 2000 assessment: Extinct

Little Quarry Lake species pair: Threatened

Paxton Lake species pair. 2010 assessment: Endangered

Vananda Creek species pair (Spectacle, Priest and Emily Lakes). 2010 assessment: Endangered


COSEWIC Reasons for status

Enos Lake species pair

This pair occurred in a single lake in south coastal British Columbia where it has now formed a hybrid swarm. Although it is possible that a small number of genetically-pure fish still exist in the lake, the ongoing presence of an invasive crayfish, and associated habitat degradation, continue to place this species at a high risk of extinction.

Hadley Lake species pair

This Canadian endemic fish was known only from Hadley Lake, Lasqueti Island, British Columbia. It was lost as a result of nest predation by the introduced brown bullhead.

Paxton Lake species pair

The species are unique Canadian endemics restricted to a single small lake in coastal British Columbia (BC). The wildlife species are highly susceptible to extinction from aquatic invasive species introductions that have been observed to cause rapid extinction of similar species in at least two other lakes. Invasive aquatic species continue to increase in lakes on adjacent Vancouver Island and the lower mainland of BC, and there is, therefore, a reasonable likelihood that invasives could be introduced into the habitat of the species over the next 10 years. The species are also susceptible to habitat loss and degradation from water extraction and land use activities in the surrounding landscape.

Vananda Creek species pair

This pair of small freshwater fish are unique Canadian endemics restricted to three small, interconnected lakes in coastal British Columbia (BC). The wildlife species are highly susceptible to extinction from aquatic invasive species introductions that have been observed to cause rapid extinction of similar species in at least two other lakes. Invasive aquatic species continue to increase in lakes on adjacent Vancouver Island and the lower mainland of BC, and there is, therefore, a reasonable likelihood that invasives could be introduced into the habitat of the species over the next 10 years. This species are also susceptible to habitat loss and degradation from water extraction and land use activities in the surrounding landscape.

Little Quarry Lake species pair

This pair of small freshwater fish are unique Canadian endemics restricted to one small lake in coastal British Columbia. The wildlife species are highly susceptible to extinction from aquatic invasive species that have been observed to cause rapid extinction of similar species in at least two other lakes. Many invasive aquatic species already occur in southwestern British Columbia, and any range expansion or introduction of new invasive species to Little Quarry Lake would likely lead to the extinction of this species pair.

© 2009-2024 Dolph Schluter