Performance of Spawner Survey Techniques at Low Abundance Levels
| Autor: | Sean P. Gallagher, Peter B. Adams, Barry W. Collins, David W. Wright |
|---|---|
| Rok vydání: | 2010 |
| Předmět: |
education.field_of_study
Chinook wind Ecology biology Range (biology) Population Endangered species Management Monitoring Policy and Law Aquatic Science biology.organism_classification Fishery Survey methodology Abundance (ecology) Oncorhynchus Environmental science education Ecology Evolution Behavior and Systematics Escapement |
| Zdroj: | North American Journal of Fisheries Management. 30:1086-1097 |
| ISSN: | 1548-8675 0275-5947 |
| DOI: | 10.1577/m09-204.1 |
| Popis: | Population monitoring is essential to know whether coastal California's Endangered Species Act–listed Chinook salmon Oncorhynchus tshawytscha, coho salmon O. kisutch, and steelhead O. mykiss stocks are progressing toward recovery. In coastal California, salmonids are at the southern edge of their range, and this one of many reasons they are not abundant. This provides unique challenges for monitoring, as different survey methods will result in estimates with different levels of accuracy and precision, which are important for evaluating population trends. For this study we intensively monitored three Mendocino County watersheds to evaluate the reliability of two-stage data for monitoring regional escapement. Under this scheme, regional spawning surveys (stage 1) were calibrated with data from intensively monitored watersheds (stage 2), where escapement was estimated using capture–recapture methods, redd counts, and fish counts. The objective of the study was to evaluate the quality of the stage 2 ... |
| Databáze: | OpenAIRE |
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