ENVS 202 On-line Access

The apparent decline of the salmon in the Columbia river system is one of the most complex environmental problems we have.

However, this problem has been over-simplified by the media and others to one single root cause, namely the construction of hydroelectric dams on the Columbia river system.

Today we wish to access of this simplification is valid. The homework assignment given will allow you to explore this issue in more depth as well. For today we want to examine some of the broader issues and look at the actual data which is available.

The Salmon controversy is an excellent example of arguments made largely on belief, instead of knowledge that is supported by the actual data .

It is also an excellent example/reflection of another problem that effectively prohibits meaningful discourse; reactive vs proactive positions

Factors Causing Salmon Decline:

Broad Brush Factors:

1. Dam Construction
2. Increased Logging
3. Changing climate patterns
4. Agriculture
5. Increased population growth
6. Over fishing

More Detailed Factors in relation to Above:

• Loss of Streamside Vegetation and Functions (2,4,5)
• Pesticide Exposure (2,4)
• Industrial Pollutants Exposure (5)
• Increased Amount Of Sediment Entering Streams (2,3,4,5)
• Habitat Destruction or reduced area (1,2,4,5)
• Decreased Amount Of Large Logs In Streams And Loss of Deep Pools and Channel Form (2,5)
• Reduced Fresh Water Flow In Rivers and Streams (1,4,5)
• Exposure to Abnormal Temperatures (1,3,4)
• Lack of Screening of Water Diversion Canals to Keep Fish Out (4)
• Reduced Upwelling (3)
• Altered Ocean Currents and Flow (3)
• Decreased Food Abundance (3)
• Reduced Numbers of Adults Reaching Their Spawning Grounds (3,6)
• Reduced Numbers of Young Fish Making It To The Sea (1,2, bird predation)
• Barriers Preventing Salmon From Migrating Upstream or Downstream (1)
• Competition Between Hatchery and Wild Fish
• Forest Fragmentation (2,5)
• Estuary Degradation (2,5)

  From P. Hurley:

  An Estimation of Historic and Current Levels of Salmon Production in the Northeast Pacific Ecosystem:

  Evidence of a Nutrient Deficit in the Freshwater Systems of the Pacific Northwest. A comparison of historic and current levels of salmon abundance was used to determine the current deficit of marine-derived nutrients for Pacific Northwest streams. This nutrient deficit may be one indication of ecosystem failure that has contributed to the downward spiral of salmonid abundance, further diminishign the possibility of salmon population recovery to self-sustaining levels.

Blue line represents growth of non-harvested fish in the Columbia River system. The implication is that competition for food/nutrients is increasing rapidly.

Its getting warmer earlier in the season with time in the Columbia river. Is this cause local (e.g. dams/ag) or global (e.g. Global Warming)

Graph shows harvesting by Tribal communities with protected fishing rights. Some degree of "over harvesting" is apparent.

During class (1998) a student made a fairly perceptive comment on the Ocean catch figure. She pointed out that the increase could be due to an increase in efficiency of catching salmon instead of just more boats on the water catching salmon. This has important implications:

• If the increase in Ocean catch is due to more boats (which is what I *believe* but can't prove) - then the Salmon population could be stable and less salmon simple reach the river systems.

• But, if we have an increase in efficiency in the way we catch Salmon then its possible that the ocean Salmon count is actually declining and the increase in ocean harvest is due to this increase in efficiency. But again, this efficiency increase would have to be large.

  That is, if the true salmon count is down by a factor of say 100, relative to what it was 100 years ago, then our salmon efficiency in harvesting would have to increase by at least a factor of 100 to make up the difference. I think this is unlikely.

This is the raw salmon count data at Boneville Dam that we will inspect more closely below. Evidence of quasi-cylical behavior is apparent.

Some relevant WWW resources for the above:

The Great Salmon Hoax

Comprehensive data source on Northwest Fish

Pacific Interdecadal Climate Change

HydroPower and the Columbia River System

Don't forget about Canada

White Men Luv Fish

Pacific Northwest Index

Canadian Harvest Increases

Some Salmon Links

• Detailed Strategy for Salmon Recovery
• An Example of a data driven process
• Paying for Salmon Recovery
• Automobile pollution and Salmon Immune systems
• Important role of El Nino
• Real time data collection
• Fishing Technology in Alaska
• Notes from a 50 year Alaska Native

The above documents and data strongly suggest that a significant reason for Columbia river salmon decline is due to increased harvests in Alaska and Canada.

This is likely a reflection of where the Salmon are and this is strongly coupled to decadel climate changes in the Alaska-BC-PNW region.

This implies, that at any particular point in this region, over timescales of 50 years, salmon counts/catches will be cyclical in nature.

So, be careful what you are told without being allowed to see the larger picture:

World Salmon Harvest

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