Study of Atlantic salmon post-smolt movement in the Gulf of St. Lawrence using an individual-based model
Authored by Kyoko Ohashi, Jinyu Sheng
Date Published: 2018
DOI: 10.1016/j.rsma.2018.08.012
Sponsors:
National Science and Engineering Research Council of Canada (NSERC)
Platforms:
No platforms listed
Model Documentation:
Other Narrative
Model Code URLs:
Model code not found
Abstract
This study examines the effect of environmental conditions and swimming
behaviors on the movement of Atlantic salmon (Salmo salar) post-smolts
(juveniles) in the Gulf of St. Lawrence (GSL) using an individual-based
model (IBM). The IBM uses time-varying and three-dimensional currents
and hydrography produced by an ocean circulation model combined with a
numerical particle-tracking scheme where swimming behaviors can be
specified. Various experiments are run using this IBM with the aim of
gaining insight into the observed movements of post-smolts documented in
a past field study. In that study, a post-smolt released from the
Saint-Jean River on the north shore of the GSL in June 2010 was found to
exit the GSL through the Strait of Belle Isle (SBI) to the northeast of
the release area. Two other post-smolts, released later in June 2010,
were detected near Anticosti Island (AI) to the southwest of the release
area. The numerical results suggest that, for both the post-smolt(s)
that moved to the SBI and towards AI, the ambient near-surface
circulation patterns favored their movements. In the case of movement
towards AI, the travel times simulated using the simulated circulation
pattern and a variety of swimming behaviors agree well with
observations. For movement towards the SBI, an efficient swimming
strategy is necessary in addition to a favorable circulation pattern in
order for simulated travel times to be similar to observations. This
study suggests two successful strategies for movement towards the SBI:
(a) swimming with currents in favorable directions and against currents
in unfavorable directions, and (b) swimming towards a series of target
locations that define a migration route. The possibility that Atlantic
salmon post-smolts originating from rivers on the north shore of the GSL
may sometimes be confined to the GSL instead of migrating to the open
ocean is consistent with past observational studies. (C) 2018 Elsevier
B.V. All rights reserved.
Tags
Migration
River
Canada
Individual-based
model
Seaward migration
Pacific salmon
Salar l.
Scotian shelf
Migratory behavior
Atlantic salmon (salmo salar)
Post-smolt
Gulf of st. lawrence
Subtidal circulation
Marine migration
Belle-isle
Postsmolts