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Ocean
Research & Conservation
Society
presents
Save the Streams:
Southern Vancouver Island Salmon
Salmon
• 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
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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.
Chinook
• Oncorhynchus tshawytscha
• Spring, Salmon, King, Blackmouth, Quinnat,
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Chub, Tyee (14+kg)
Chinooks have a greenish-blue dark back with
long black spots
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 and 14 kg.
Spawning peak, May to June and August to
September.
Chum
• Oncorhynchus 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
Coho
• Oncorhynchus kisutch
• Silver Salmon
• Spawning males are red on their sides, and a
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bright green on the back and head areas, with a
darker colouration on the belly, and spots on
upper tail fin lobe. They also develop a hooked
jaw with sharp teeth.
Females develop a lesser-hooked snout.
reach 1 m and weigh up to 14 kg
average between 3 to 5 kg.
Spawning peak, July to August.
Sockeye
• Oncorhynchus nerka
• Kokanee, Red Salmon, Blueback Salmon
• Varying shades of red resulting in a
brilliant scarlet fish with a green head.
• Grow to 83 cm
• weigh up to 7 kg
• Spawning peak month, August
Pink
• Oncorhynchus gorbuscha
• Humpies
• Pale grey
• males develop a hump
• up to 76 cm and to 5.5 kg
• average 1.5 to 2.5 kg
• Spawning peak month, October
Southern Vancouver Island:
Salmon Spawning Streams and Rivers
Threats
• 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
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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, fish farms, and
global warming
Actions
• 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:
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disease
pollution (including contaminating shellfish)
predation on young wild salmon
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
– choosing wild salmon over farmed
Summary
• Salmon – 5 species
– Chinook
• 48+kg, dorsal spots
– Chum
• 12+kg, male checkerboard
– Coho
• 5+kg, red sides, green back
– Sockeye
• 7+kg, red body, green head and tail
– Pink
• 3+kg, male hump
• Threats – farming, forestry,
oceansociety.blogspot.com
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pollution, urbanization, global
warming.
Actions – stream cleaning,
recycling, using biodegradable,
organic, and choosing wild salmon.