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SALMON ATLAS 3A
Does catch-and-release angling alter the migratory behaviour of Atlantic salmon?
Publication year: 2010
Source: Fisheries Research, In Press, Accepted Manuscript, Available
online 3 September 2010
Jenny L.A., Jensen , Elina, Halttunen , Eva B., Thorstad , Tor F., Nęsje , Audun
H., Rikardsen
Electronic tracking studies have recently focused on the potential negative
effects of catch-and-release (C&R) angling in Atlantic salmon (Salmo salar L.).
Common for these studies is that the fish were tagged between C&R, and the
effects of C&R can thus not be separated from the extra handling effects
associated with the tagging procedure. In addition, reference groups and
information on the behaviour prior to C&R is not available. In this study, 95
homing multi-sea-winter Atlantic salmon were tagged with radio transmitters in
the fjord before entering the River Alta, Northern Norway, and thereafter
manually tracked until the spawning period. Ten of these salmon were caught and
released by anglers in the river. All ten fish survived the angling event, and
nine were observed in known spawning areas in the spawning period. No difference
in migratory behaviour prior to or after C&R was observed between caught and
released fish and the reference group. Individuals both among the C&R fish and
the reference group showed downstream movements and migratory stops associated
with C&R in previous studies. In spite of making studies logistically more
challenging and expensive, the use of reference groups is important when
assessing natural versus non-natural behaviour and to separate C&R effects from
tagging effects.
4th September 2010 04:47