From
lampreys to sturgeon, the fish of British Columbia are as
diverse as their body forms and life histories.
Native Fish
British Columbia contains a diverse and dynamic, sometimes rapidly
evolving fish community. The province was almost completely
covered by a layer of ice only about 10,000 years ago, during
the Pleistocene Ice Ages. As the glacial ice melted and retreated,
it provided opportunities for fish surviving in ice-free
areas to move into new habitat. Some early colonizers became
isolated from other populations by waterfall barriers as
the land rose upward after the weight of the ice was removed.
Since much of B.C. has been colonized for such a short period,
it is often not clear what is a species, a subspecies or
a distinct population. However, since relatively few freshwater
species were able to move into our area before dispersal
routes were cut off, much of our natural diversity occurs
at the population level rather than the species level. (For
example: coastal rainbow trout, Kamloops trout, Gerrard trout
and steelhead are all considered the same species even though
they appear very different.) We currently recognize 81 distinct
Native Freshwater Fishes including
species and subspecies; some have not been
scientifically described and named. Four
species are now extinct.
Native
species are populations that are known to have existed at
a site prior to the influence of humans.
See
the B.C. Fish Facts factsheets
for
pictures and information on 20 of our native freshwater fishes.
Introduced Fish
 In
British Columbia we are the stewards of a unique natural
biological heritage. In the past, high value was placed on
a limited number of species of special commercial or recreational
use. There has been a growing concern with conservation and
the maintenance of biodiversity over the last two decades.
Current fisheries managers recognize the need for healthy
natural aquatic ecosystems to support a variety of recreational
opportunities and to maintain options for future generations
of our citizens.
The release of species into ecosystems where they do not occur
naturally is a risky activity. The outcome can be unpredictable
and undesirable. This is because we do not understand all
the interactions between species. We do know that in order
to coexist the species within a community have adapted to
live together and the introduction of a new species can cause
the system to collapse. Undesirable results have occurred
from the release of new species to British Columbia’s
waters. Examples include: 1) the unlawful introduction of
a catfish (Ameriurus nebulosus) in Hadley Lake brought
about the extinction of a unique pair of sticklebacks; and
2) the introduction of opossum shrimp (Mysis relicta)
to Kootenay Lake (in an attempt to improve growth in small
rainbow trout) contributed to the collapse of the kokanee
stock (reducing the food supply and survival of larger rainbow).
There are Introduced Freshwater
Fishes in all regions of the province.
PLEASE
DON’T MOVE LIVE FISH OR OTHER AQUATIC LIFE
from one place to another.
To find out more about fish in B.C. visit the British
Columbia Fishwizard and for fish from around the world, Fishbase is
a global information system that has some great fish photos!
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