First summer growth predetermined in anadromous and resident brook charr
Abstract:Early growth of wild, anadromous and non-anadromous (resident) brook charr Salvelinus fontinalis was compared under controlled laboratory conditions. Offspring were collected as they emerged from natural redds in the Miramichi River, New Brunswick, Canada. Anadromous offspring were initially longer and heavier than residents. Anadromous offspring had lower specific growth rates during their first 2 months post-emergence, but surpassed residents by the third month. Consequently, anadromous offspring remained larger at the end of 3 months and it is concluded that they had a predetermined, maternal and genetic advantage related to body size, rather than an environmentally determined advantage during their first summer of growth. Other studies hypothesize that juvenile development affects life-history strategy adopted as adults, which suggests anadromy in this population may be, at least in part, predetermined by maternal and genetic effects.
Document Type: Regular Paper
Affiliations: Canadian Rivers Institute, New Brunswick Cooperative Fish and Wildlife Research Unit, Department of Biology, University of New Brunswick, Bag Service 45111, Fredericton, New Brunswick, E3B 6E1, Canada
Publication date: February 1, 2007