Selective action of gillnets on sockeye (Oncorhynchus nerka) and pink salmon (O. gorbuscha) stocks of the Skeena River system, British Columbia ...
Exploitation of Skeena River sockeye salmon (Oncorhynchus nerka) has been conducted almost solely by drift gillnets since inception of the commercial fishery in 1877. Selective action of gillnets is a factor which may have contributed to a long term decline in sockeye production and to other feature...
| Main Author: | |
|---|---|
| Format: | Text |
| Language: | English |
| Published: |
University of British Columbia
2011
|
| Subjects: | |
| Online Access: | https://dx.doi.org/10.14288/1.0104120 https://doi.library.ubc.ca/10.14288/1.0104120 |
| Summary: | Exploitation of Skeena River sockeye salmon (Oncorhynchus nerka) has been conducted almost solely by drift gillnets since inception of the commercial fishery in 1877. Selective action of gillnets is a factor which may have contributed to a long term decline in sockeye production and to other features of the population biology. This study was designed to determine the selective properties of nylon gillnets presently in use; to compare these with properties of linen nets used prior to 1955; to adjust age composition estimates of escapement levels prior to 1946; and to re-examine brood year production. In addition, the selective action was examined of the fishery as a whole on sockeye and pink salmon (O. gorbuscha) in 1968. The selective properties of six nylon gillnets ranging in mesh size between 4-5/8 inches and 5-5/8 inches, which corresponded with sizes normally used in the commercial fishery, were to be determined through a simultaneous fishing experiment, and selectivity curves were computed by Holt's ... |
|---|