Background
The Oregon Salmon Plan was established by the Oregon Legislature to deal with declining numbers of salmon in Oregon rivers in the last 20 years. Several species, notable Coho salmon, have declined to such an extent that they may be listed among Threatened and Endangered Species. The Salmon Plan includes restoration of habitat, assessment of the effects of dams on salmon populations, and ongoing monitoring.
Recent research has indicated that salmon returns correlate
strongly with climatic and ocean conditions in the Northwest.
There is strong evidence for multi-decadal periods of generally
cool and wet conditions alternating with warm and dry periods.
The former are associated with high return rates of salmon to
the Columbia and other rivers in the Northwest, while the warm
and dry periods correspond to much lower salmon return rates.
If it is assumed that climate, stream and ocean conditions affect
salmon populations, then any salmon enhancement strategies or
evaluation of the success of those strategies should include those
conditions.
In its original form, the Oregon Salmon Plan made no mention of variations in climate and ocean conditions as part of the evaluation tasks. In the spring of 1997, however, this oversight was detected, and an effort was made to establish a technical group to provide ongoing information on these "background" conditions. The Climate, Hydrology and Ocean Studies (CHaOS) Team began meeting in the fall of 1997, with several major tasks defined:
1. Determine month-to-month and seasonal variations in physical parameters affecting salmon populations:
2. Submit monthly reports to the Governor, Legislature, Agencies, and others affiliated with the Salmon Plan.
3. Make summary reports available on the Web.
4. Submit an annual report to the Governor.