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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.


M. Newton

J. Barry

M. C. Lucas

P. Boylan

C. E. Adams


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
Public URL