Does size matter? A test of size‐specific mortality in Atlantic salmon Salmo salar smolts tagged with acoustic transmitters

Newton, M.; Barry, J.; Dodd, J. A.; Lucas, M. C.; Boylan, P.; Adams, C. E.

Abstract

Mortality rates of wild Atlantic salmon Salmo salar smolts implanted with acoustic transmitters were assessed to determine if mortality was size dependent. The routinely accepted, but widely debated, ‘2% transmitter mass: body mass’ rule in biotelemetry was tested by extending the transmitter burden up to 12·7% of body mass in small [mean fork length (LF) 138·3 mm, range 115–168 mm] downstream migrating S. salar smolts. Over the short timescale of emigration (range 11·9–44·5 days) through the lower river and estuary, mortality was not related to S. salar size, nor was a relationship found between mortality probability and transmitter mass: body mass or transmitter length: LF ratios. This study provides further evidence that smolt migration studies can deviate from the ‘2% rule’ of thumb, to more appropriate study‐specific measures, which enables the use of fishes representative of the body size in natural populations without undue effects.

• Journal Article Type: Article
• Acceptance Date: May 23, 2016
• Online Publication Date: Jun 28, 2016
• Publication Date: 2016-09
• Deposit Date: Oct 17, 2019
• Journal: Journal of Fish Biology
• Print ISSN: 0022-1112
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 89
• Issue: 3
• Pages: 1641-1650
• DOI: https://doi.org/10.1111/jfb.13066
• Public URL: http://researchrepository.napier.ac.uk/Output/1802903