Swimming performance and associated ionic disturbance of juvenile pink salmon Oncorhynchus gorbuscha determined using different acceleration profiles
Abstract:Swimming performance was assessed in juvenile pink salmon Oncorhynchus gorbuscha (body mass <5·0 g) using five different protocols: four constant acceleration tests each with a different acceleration profile (rates of 0·005, 0·011, 0·021 and 0·053 cm s−2) and a repeated ramped-critical swimming speed test. Regardless of the swim protocol, the final swimming speeds did not differ significantly (P > 0·05) among swim tests and ranged from 4·54 to 5·20 body lengths s−1. This result supports the hypothesis that at an early life stage, O. gorbuscha display the same fatigue speeds independent of the swimming test utilized. Whole body and plasma [Na+] and [Cl−] measured at the conclusion of these tests were significantly elevated when compared with control values (P < 0·05) and appear to be predominantly associated with dehydration rather than net ion gain. Given this finding for a small salmonid, estimates of swim performance can be accurately measured with acceleration tests lasting <10 min, allowing a more rapid processing than is possible with a longer critical swim speed test.
Document Type: Regular Paper
Affiliations: 1: Department of Zoology, University of British Columbia, 6270 University Blvd., Vancouver, BC V6T 1Z4, Canada 2: The Faculty of Land and Food Systems, University of British Columbia, 2357 Main Mall, Vancouver, BC V6T 1Z4, Canada
Publication date: November 1, 2009