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Type: Journal Article

Title: Sea lice (Lepeophtheirus salmonis) infection rates on juvenile pink (oncorhynchus gorbuscha) and chum (Oncorhynchus keta) salmon in the nearshore marine environment of British Columbia, Canada.

Date: March 2 2004

Author(s): Alexandra Morton; Richard Routledge; Corey Peet; Aleria Ladwig

Journal Name: Canadian Journal of Fisheries and Aquatic Science

Volume: 61

Pages: 147-157

Description: This study compared sea lice (Lepeophtheirus salmonis) infestation rates on juvenile pink (oncorhynchus gorbuscha) and chum (Oncorhynchus keta) salmon in five nearshore areas of the British Columbia coast selected on the basis of proximity to salmon farms. A 10-week study in the Broughton Archipelago found sea lice were 8.8 times more abundant on wild fish near farms holding adult samon and 5.0 times more abundant on wild fish near farms holding smolts than in areas distant from salmon farms. We found that 90% of juvenile pink and chum salmon sampled near salmon farms in the Broughton Archipelago were infected with more than 1.6 lice-(g host mass), a proposed lethal limit when the lice reach mobeile stages. Sea lice abundance was near zero in all areas without salmon farms. Salinity and temperature differences could not account for the higher infestation rates near the fish farms. The most immature life stages dominated the lice population throughout the study, suggesting the source of lice was a stationary, local salmonid population. No such wild population could be identified. The evidence from this control-impact study points to a relationship between salmon farms and sea lice on adjacent, wild, juvenile, salmon.

Physical Description: 11-page report

Office: Clayoquot Biosphere Trust

Document Location: CBT Library - Filing Cabinet

Document Identifier: FISr/MOR

Use Constraints: Office Use Only

Geographic-specific: Broughton Archipelago, Bella Bella, Prince Rupert, Smith Inlet, Rivers Inlet

Geographic-general: Other, Pacific Northwest

Format: Print

Language: English