Science Inventory

ESTIMATING THE SIZE OF HISTORICAL COASTAL OREGON SALMON RUNS

Citation:

Meengs, C. AND R T. Lackey. ESTIMATING THE SIZE OF HISTORICAL COASTAL OREGON SALMON RUNS. Presented at Annual Meeting of the Oregon Chapter, American Fisheries Society, Corvallis, Oregon, February 16-18, 2005.

Description:

Increasing the abundance of salmon in Oregon's rivers and streams is a high priority public policy objective. Salmon runs have been reduced from pre-development conditions (typically defined as prior to the 1850s), but it is unclear by how much. Considerable public and private resources have been devoted to restoring salmon runs, but it is uncertain what the current recovery potential is because much of the freshwater and estuarine habitat for salmon has been altered and there is no expectation that it will be returned to a pre-development condition. The goals of all salmon recovery efforts are based on assumptions, often unstated, about the size of the runs prior to significant habitat alteration, coupled with an estimate of the amount and quality of freshwater and estuarine habitat currently available. Current run sizes in coastal Oregon may approximate the recovery potential of the existing salmon habitat. Conversely, recovery potential may be higher even given the available freshwater and estuarine habitat. We estimated the historical aggregate salmon run size in rivers along the Oregon coast excluding the Columbia River using two methods: (1) converting estimated aboriginal population levels into numbers of salmon; and (2) extrapolating cannery pack into numbers of salmon. Annual aboriginal harvest of all salmon species is estimated to have been approximately 10 million pounds/year or 1.75-5.36 million salmon, a harvest level similar to that occurring during the height of commercial fishing on Oregon's coastal rivers in the late 1800s and early 1900s. Extrapolating cannery pack data, the estimated size of the late 1800s aggregate runs of Coho salmon (Oncorhynchus kisutch) was 1.5-2.5 million. The estimated size of aggregate runs of Chinook salmon (Oncorhynchus tshawytscha) runs was 290,000-517,000. Compared to our estimates of mid-1800s Coho salmon levels, early 2000 runs (during favorable ocean conditions), are 11-19% of the historical level. During poor ocean conditions (1990s), current Coho salmon runs are 3-6% of the historical size.

*The views and opinions are those of the authors and do not necessarily represent those of any organization.

Record Details:

Record Type:DOCUMENT( PRESENTATION/ ABSTRACT)
Product Published Date:02/16/2005
Record Last Revised:06/21/2006
Record ID: 89965