The early development of hybrids between brook charr (Salvelinus fontinalis) and Arctic charr (Salvelinus alpinus)

Reciprocal hybrids between brook charr and Arctic charr were compared to parental species from fertilization to 10 weeks after the beginning of feeding. At the end of the experiment, higher survival rates (58.6% ± 1.5) were observed for brook charr (FF) than for Arctic charr (AA: 48.1% ± 2.2), while both hybrids were intermediate (Arctic charr dam × brook charr sire (AF): 57.5% ± 0.9; brook charr dam × Arctic charr sire (FA): 53.8% ± 1.4). All during the studied period, survival rates of hybrids were intermediate to parental species. Effects of parental species on the length of the incubation period (LIP) were significant but differed according to dam and sire species. LIP was 431.8 ± 0.9 degree-days for AF, 454.4 ± 2.2 for AA, 503.4 ± 0.9 for FF, and 518.6 ± 1.6 for FA. Individual sire effects on early survival and on the length of incubation period showed significant sire effects only on the length of the incubation period and only among brook trout sires in pure species.