Anadromy and the dispersal of an invasive fish species (Oncorhynchus mykiss) in Eastern Quebec, as revealed by otolith microchemistry
Resource
Ecology of Freshwater Fish, 19(3), 348-360
Journal
Ecology of Freshwater Fish
Journal Volume
19
Journal Issue
3
Pages
348-360
Date Issued
2010-09
Date
2010-09
Author(s)
Thibault, I.
Hedger, R.D.
Dodson, J.J.
Shiao, J.-C.
Iizuka, Y.
Tzeng, W.-N.
Abstract
Rainbow trout (Oncorhynchus mykiss) is invading rivers bordering the St. Lawrence Estuary (Quebec, Canada). Some rivers in Eastern Quebec support self-sustaining populations while adult vagrants are frequently captured in rivers where no reproduction has been confirmed. We hypothesised that the development of anadromy has promoted the species dispersal. Otolith Sr:Ca analyses revealed that although all fish captured in the upstream stocking region were freshwater residents, both anadromous and freshwater resident phenotypes were found downstream in Eastern Quebec. The proportion of fish exhibiting the anadromous life cycle increased with the distance from the stocking zone. Eastern Quebec steelhead migrated to sea at the same age but at a larger size than steelhead within their native range. Age at first reproduction was similar to that observed in native populations. The development of the anadromous life cycle enables this species to colonise new rivers following long-distance migrations along the St. Lawrence Estuary corridor.
Subjects
exotic fish invader
hierarchical filter
dispersion capacity
anadromy
freshwater residency
otolith microchemistry
File(s)![Thumbnail Image]()
Loading...
Name
24.pdf
Size
735.19 KB
Format
Adobe PDF
Checksum
(MD5):acf084f2f8e9f67c175c84fc9e1120ac