FISH OF RICHMOND
by
Habitat Biologist, Fisheries and Oceans Canada
Introduction
About 15,000 years ago, no fish would have been present in the area now known as British Columbia as the area was covered with ice. Between 15,000 and 11,000 years ago, the ice gradually melted. Depressions left in the land surface as the ice melted formed lakes drained by rivers. Fish moved into these lakes and rivers from areas that were not covered with ice. Fish likely entered the Fraser River from unglaciated areas of the Fraser River and Columbia River systems to the south or from the sea. (Carl et. al., 1967).
Aquatic habitats in or about the City of Richmond mainly include those associated with a) the Fraser River estuary and b) the many drainage waterways within the dike surrounding the City of Richmond.
The Fraser River Estuary
The Fraser River forms the largest estuary along the Pacific Coast of North America. The mixing of fresh river water with saline marine water in estuaries creates an environment that supports a rich and diverse aquatic community. The variation in salinity from the marine waters at its mouth (for example, Sturgeon Bank) to freshwater farther upstream is a main contributor to the diversity of fish species found in the Fraser River estuary in the City of Richmond area.
Drainage Waterways in the City of Richmond
Historically, naturally created watercourses in the City of Richmond would have been directly connected to the Fraser River. Over the years, many of these watercourses have been realigned or straightened and, as a result of construction of the dike surrounding the City of Richmond, many of the watercourses are now separated from the Fraser River by water control structures. However, the water control structures connecting drainage waterways in the City of Richmond and the Fraser River may allow fish to move between the drainage waterways and the Fraser River depending on each structure's design and operation. On this basis, any fish species recorded as being present in the Fraser River estuary has the potential to be present in any of the drainage waterways assuming the environmental conditions in the drainage waterway are suitable for the respective fish species. For example, due to the presence of mainly freshwater in most of the drainage waterways, it is unlikely that marine species present in the Estuary would be present in any of the drainage waterways.
Fish Species at Risk
The following fish species in the City of Richmond have been designated by COSEWIC (Committee On the Status of Endangered Species In Canada) as Endangered or of Special Concern or by the British Columbia Data Conservation Centre (BCDCC) as Red-Listed or Blue-Listed.
COSEWIC defines Endangered as a species facing imminent extirpation or extinction and defines Special Concern as a species of special concern because of characteristics that make it is particularly sensitive to human activities or natural events.
BCDCC defines a Red-Listed species as any species that have or are candidates for Extirpated, Endangered, or Threatened status in British Columbia. Extirpated taxa no longer exist in the wild in British Columbia, but do occur elsewhere. Endangered taxa are facing imminent extirpation or extinction. Threatened taxa are likely to become endangered if limiting factors are not reversed. A Blue-Listed species includes any species considered to be of Special Concern (formerly Vulnerable) in British Columbia. Taxa of Special Concern have characteristics that make them particularly sensitive or vulnerable to human activities or natural events. Blue-listed taxa are at risk, but are not Extirpated, Endangered or Threatened.
None of the fish species in the City of Richmond are on Schedule 1 of the federal Species At Risk Act (SARA). Schedule 1 is the official list of wildlife species at risk in Canada. It includes species that are extirpated (extinct in Canada), endangered, threatened, and of special concern. Once a species is listed on Schedule 1, protection and recovery measures are developed and implemented. Species on Schedule 2 or 3 of SARA have been designated at risk by COSEWIC but need to be assessed before possible inclusion onto Schedule 1.
Fish Species at Risk in Richmond, BC
White Sturgeon (Acipenser transmontanus): Endangered (COSEWIC), Red-Listed (BCDCC) & SARA Schedule 3
Green Sturgeon (Acipenser medirostris): Special Concern (COSEWIC), Red-Listed (BCDCC) & SARA Schedule 3
Eulachon (Thaleichthys pacificus): Blue-Listed (BCDCC)
Coho Salmon (Oncorhynchus kisutch) – Interior Fraser Population: Endangered (COSEWIC)
Cutthroat Trout (Oncorhynchus clarki): Blue-Listed (BCDCC)
Dolly Varden (Salvelinus malma): Blue-Listed (BCDCC)
Sockeye Salmon (Oncorhynchus nerka) – Cultus Population: Endangered (COSEWIC)
Brassy Minnow (Hybognathus hankinsoni): Candidate for assessment by COSEWIC
View the checklist of Fish of Richmond, by Brian Naito