Friday, August 17, 2007

Save the Streams


There are five species of Pacific salmon that die
after spawning; Chinook, Chum, Coho, Sockeye,
and Pink. Salmon return to their natal streams and
rivers each year. Salmon travel thousands
of miles and spend one to five years feeding in the
ocean before returning to their birth streams.
Spawning females dig out a gravel nests, called a
redd. The males then fertilizes the eggs and the
female protects the redd for one to two weeks.
Alveins hatch and mature into fry, developing
vertical bars for camouflage, called parr marks.
After a period of feeding fry migrate downstream
towards the ocean and grow into smolts adapting
to their marine environment.

On top of natural dangers from predators dangers
to salmon from human activities include poor
farming and forest practices, pollution, destruction
of coastal wetlands and estuaries. The territory of
British Columbia salmon has been decimated for
decades by industrial clearcut logging. Roots of
trees anchor steep slopes. Logging increases the
chances of landslides filling vital spawning
grounds with mud, debris, and boulders. Shade
from trees is lost increasing water temperatures.
Other threats include overfishing, urbanization,
hydroelectric dams, and fish farms.

Salmon play an important role sustaining
forest ecology. Spawners bring vital nutrients
from the ocean into the forest. Carcasses are dispersed
by bears and eagles providing the trees with fertilizer;
nitrogen, phosphorus, and carbon. Salmon feed the
rivers helping the survival of young salmon. Farmed
salmon does not replicate this vital role and is
detrimental to wild stocks. Dangers from fish farms
include disease, pollution (including contaminating
shellfish), predation on young wild salmon, and
escapement (Atlantic salmon compete for food and
habitat with wild stocks). Conservation actions include
cleaning up salmon streams (ensuring clean and safe
flowing environments), recycling, using biodegradable
and organic products, and choosing wild salmon over

Oncorhynchus tshawytscha
Spring, Salmon, King, Blackmouth,
Quinnat, Chub, Tyee (14+kg)
Chinooks have a greenish-blue dark back with
long black spots, a red hue develops around
the fins and belly, male teeth are enlarged and
they have a hooked snout. Tyee reach 1.5 m
and 58 kg, average 90 cm and14 kg. Spawning
peak May to June and August to September.

O. keta
Dog Salmon
Females are a metallic
blue, males have a
checkerboard colouration,
a dark horizontal stripe, and
canine-like teeth. Average
from 4.5 to 12 kg. Spawning
peak month October.

O. kisutch
Silver Salmon
Spawning males are red on
their sides, and a bright green
on the back and head areas, with a
darker colouration on the belly, spots
on upper tail fin lobe. They also develop
a hooked jaw with sharp teeth. Females
develop a lesser-hooked snout. Coho
reach 1 m and weigh up to 14 kg, they
average between 3 to kg. Spawning
peak July to August.

O. nerka
Kokanee, Red Salmon,
Blueback Salmon
Varying shades of red resulting
in a brilliant scarlet fish with a
green head. Grow to 83 cm
and weigh up to 7 kg. Spawning
peak month August.

O. gorbuscha
Pale grey, males
develop a hump.
Get up to 76 cm
and to 5.5 kg,
average 1.5 to 2.5 kg.
Spawning peak month


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