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papers>oil in marine ecosystems>
A Coming Salmon Apocalypse?
Ultimately, the biggest threat oil may pose to salmon comes from burning the oil and from the oil's contribution to global warming. Many global climate models predict a doubling of CO2, and a 3° C temperature increase during next 50 years. For B.C.'s salmon, warmer temperatures are bad news spawning, incubation, and emergence are all influenced by stream temperature.
Dr. Kees Groot, a retired salmon scientist, predicts that a 3° C increase would shorten total incubation time (egg to emergence) in B.C. salmon by 55 to 131 days. Earlier emergence and emigration of salmon may, in turn, lead to:
- Juvenile fish being out of phase with food production;
- A greater proportion returning as jacks;
- Smaller fish and lower survival.
In terms of a "life history strategy," it is better to be a bigger salmon than a smaller one. Provincial biologists have clearly shown that body size in juvenile steelhead is directly correlated with their chances of surviving to spawn. Size confers an advantage when competing for food, avoiding predators, and mating.
Salmon also exhibit well-defined temperatures preferences in the high Pacific.
Salmon temperature preferences in North Pacific waters
Winter < 7° C
Spring < 10° C
Summer < 15° C
A 3° C rise will decrease preferred habitat, and increase competition for both food and space. Ultimately, this means fewer salmon in our future. It might thus be time to consider using energy sources that are cleaner and less risky than B.C.'s offshore oil.
Impact Summary
While inustry and others suggest that the risk is low, the Heiltsuk are concerned that oil exploration might still pose a threat to B.C.'s costal ecysystems from:
- Physical impacts (coating) of oil
- Mutagenic, carcinogenic, and toxic impacts of even minute amounts of Polycyclic Aromatic Hydrocarbons
- Condoning and continuing the contribution of fossil fuels to global warming, and the anticipated warming impacts on salmon and humans.
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