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Fish and Wildlife Branch
Provincial Fish Stocking
Program
The provincial
fish stocking program is now delivered by the Freshwater
Fisheries Society of B.C.(FFSBC) in partnership with the
Ministry of Environment. They stock
approximately 9 million fish into about 1,000 lakes and
streams throughout the province annually. For more information
on the Society go to their web site at http://www.gofishbc.com
Freshwater fishing is
an important recreational and economic activity. Approximately
400,000 licenced anglers spend $400-500 million on freshwater
fishing in B.C. each year. Recent surveys show that about
one-half of the angler effort in fresh water takes place
on lakes stocked by provincial hatcheries.
MARKED FISH FIN IDENTIFICATION
Attention Anglers
Check sport-caught fish for a missing pelvic or adipose
fin, a clipped maxillary jaw-bone or attached tags. Report
any observed markings to the nearest provincial Fisheries
office or hatchery.
The Freshwater Fisheries
Society of B.C. operates five hatcheries: Vancouver Island
Trout Hatchery at Duncan, Fraser Valley Trout Hatchery
at Abbotsford, Summerland Hatchery near Penticton, Clearwater
Hatchery at Clearwater and Kootenay Hatchery near Cranbrook.
In addition, a seasonal holding facility in Prince George
receives fish transferred from the production hatcheries
for distribution to the northern part of the province.
Species stocked include
rainbow, cutthroat and steelhead trout, brook char and
kokanee. Most of the eggs taken to produce these fish
are collected from wild native stocks, making B.C.'s fish
culture program unique in North America.
Fish are stocked during
the spring and fall. Spring stocking takes place after
the ice goes from the lakes and before the water gets
too warm. Fall stocking takes place when warm summer water
temperatures start to abate. The spring stocked fish are
typically 10-20 cm. in length; fish released in the fall
are much smaller (5 cm.).
Fish are transported in
tanks of various sizes filled with water and supplied
with a continuous flow of oxygen. Trucks transporting
these tanks range in size from pickups to five-ton trucks
to semi-trailers. Helicopters, float planes, ATVs and
even backpacks are used to get fish to lakes not easily
accessible by truck.
Of the 200,000 lakes and streams in the province, about
2,500 are stocked. Stocked lakes must have public access
and be productive enough to support a reasonable fishery.
Broodstock Capture
and Egg Collection
CAPTURE: Methods
of capturing wild brood fish for egg collection purposes
include trap-netting, angling, seining and tooth-entanglement
in nets, however, the most common method of capture involves
placing a temporary fence across a spawning stream. As
the fish swim upstream to spawn, they are guided through
funnel-shaped entrances into trap pens. Fish culturists
transfer the trapped fish to on-site holding pens where
they are kept until they are sexually mature and can be
artificially spawned.
Fish culturists from the coastal hatcheries take
anadromous, or river run, wild fish from some of their
egg collection sites directly to the hatchery where
the fish are held in isolation containers for several
months before spawning.
EGG COLLECTION: A variety of
artificial spawning methods are used to collect eggs.
Most commonly the anethesized fishes' abdomen is gently
pressed to release eggs or sperm into a basin. Eggs
and sperm are mixed thoroughly to ensure fertilization
and then disinfected with an iodine based solution to
remove external bacteria.
After spawning trout and char are returned to their
native streams so that they may spawn in following years.
Kokanee are also returned to their spawning streams
but, like other salmon, die after spawning.
FISH HEALTH: Fish stocks used for brood
purposes are checked regularly by the Ministry's fish
health laboratory to ensure that viruses, bacteria and
parasites do not enter the hatchery system or stocked
waters.
Rearing
At the hatchery, eggs are placed in vertically stacked
trays or upwelling “jar” incubators. Fresh
water runs continuously through the incubators supplying
the eggs with oxygen.
EYED EGGS: About three weeks after fertilization,
eyes of the developing embryo appear as two black
spots within the tiny egg.
ALEVINS: Four to six weeks after fertilization,
the embryonic trout (alevin) struggles out of the
egg case.
FRY: Approximately eight to ten
weeks after fertilization, the nourishment in the alevin's
yolk-sac is depleted and the young fish (fry) swim-up
and begin to feed.
Fry are placed
in stainless steel rearing troughs where they are fed
several times per hour from automatic feeders. Since
disease can spread quickly, the rearing containers and
hatchery environment is kept scrupulously clean. Fish
are monitored constantly for signs of ill health which
are reported immediately to the fish health lab for
diagnosis.
Later, fry are moved to raceways or
rearing ponds at the hatchery or to net enclosures in
freshwater lakes and reservoirs.
Stocking
When regional fisheries biologists have determined
that a lake or stream requires additional fish, they
make a stocking request to the fish culture program.
The request indicates the size, age, species and strain
of fish desired and if the system should be stocked
annually. The biologist has considered the current
angling pressure, availability of food and number
of predators in the system. When the release site
has good road access, fish are moved from the hatchery
in a fish transport truck. Fixed-wing aircraft and
helicopters are used to transport fish to remote high-elevation
or hard-to-access lakes and streams.
FIXED-WING AIRCRAFT: Fish are placed in portable
containers for travel and supplied with oxygen. As
the plane approaches the lake, fish are transferred
to a hopper and released through a trap door while
the plane flies approximately 60 metres over the lake
at 130 km/hr. Tests have shown that mortality is negligible
for small fish stocked in this manner.
HELICOPTER:
Helicopters can hover directly over a lake or stream
while fish are being released. A specially designed
container, divided into compartments and suspended beneath
the helicopter, has been developed to release fish into
coastal river systems.
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