Written by: Dr. Eric Taylor, Director of the Fish Collection, Beaty Biodiversity Museum
The introduction of exotic species and their potential to become invasive is one of the leading causes of the declining status of native biodiversity. In addition, costs to the economy from the prevention, control, elimination, and the mitigation of effects of exotic/invasive species, and costs from lost opportunities are estimated to be in the hundreds of billions of dollars per year worldwide. For Canadian freshwater fishes, exotic/invasive species are the second most important cause of extinction or extirpation (after habitat loss and degradation).
The Goldfish, Carassius auratus, is native to freshwater areas of central Asia, China and perhaps Japan. The Goldfish has been domesticated for over 1000 years, usually for ornamental reasons, which has contributed to its being one of the top five most commonly introduced freshwater fishes in the world. Interestingly, Goldfish are one of the very few vertebrates with a unique metabolic pathway involving the production of ethanol in the blood which contributes to it being capable of persisting under conditions of very low oxygen levels (such at the bottom of lakes during wintertime).
Recently, several Goldfish were spotted in the Biodiversity Research Centre’s (BRC) water feature that runs between the BRC and the Fisheries Centre. While these fish (see photo) were undeniably beautiful, attracted some interest from viewers, and are relatively benign exotics (they are not major predators of other fishes) it was decided to remove them from the water feature. First, we should not knowingly promote the introduction or existence of exotic species especially on BRC grounds. Second, the ultimate location of discharge of the water feature is unclear and it is possible (although unlikely) that some fish could make their way into nearby natural water courses such as Musqueam (“TinCan”) Creek. Finally, even if the Goldfish did not leave the water feature on their own, there is always the possibility that someone could remove them from the water feature and introduce them somewhere else where they may do more harm.
Ultimately, twelve Goldfish were removed from the BRC water feature. They will be donated to the public education group of the Beaty Biodiversity Museum to assist in programs introducing people to the issue of exotic/invasive species in BC and Canada.
Photo: Some of the twelve Goldfish removed from the Biodiversity Research Centre water feature. Photo credit: Lesha Koop, Beaty Biodiversity Museum