World Aquacluture Magazine - September 2020

WWW.WA S.ORG • WORLD AQUACULTURE • SEP TEMBER 2020 57 char (141-367 mmTL), compared to the same number of brook trout (122-314 mmTL) and Arctic char (112-433 mmTL, Fig. 10). The average coefficient of condition (K) indicated that the weight of hybrid Arctic char at a given length (K = 1.21) was greater than that of brook trout (K = 1.16) and Arctic char (K = 0.92). Hybrid Growth and Survival Hybrid Arctic char demonstrate hybrid vigor (Sutterlin et al . 1977). The growth rate of hybrid Arctic char was comparable to brook trout in this study, although hybrid Arctic char grew faster than pure strain brook trout in the study conducted by Sutterlin et al. (1977). Hybrid Arctic char grew faster than pure strain Arctic char at the Cobleskill hatchery. Further, survival following spawning and total biomass production was better in Arctic char hybrids than in brook trout raised in cold water (Dumas et al . 1996). Conclusion Hatchery-reared hybrid Arctic char are much more successful reproducing at NewYork’s photoperiods and groundwater temperatures than pure Arctic char. While fertilization, eye-up and hatching success was variable between pairings, there was net improvement between generations. Unfortunately, the hybrid Arctic char do not breed true. Even after ten generations of strong selection against the vermiculations characteristic of brook trout, there was still a significant percentage of hybrid Arctic char with dorsal vermiculations. A similar phenomenon seems to have naturally occurred in northern Quebec, where brook trout and Arctic char introgressed leaving apparent “brook trout” populations carrying Arctic char genes (Bernatchez et al . 1995, Glemet et al . 1998). Arctic char × brook trout hybrids have a greater condition factor than pure strain Arctic char or brook trout. Further, in several places in Europe, the flesh fromArctic char × brook trout hybrids is highly appreciated by consumers (Gross et al . 2004). However, it may be too early to recommend or dismiss Arctic char hybrids as an alternative for coldwater fish farming in the United States. The results from this study encourage further consideration. Perhaps with more sophisticated breeding techniques and DNA analysis, hatch rates and morphological characteristics will be improved so that the culture of Arctic char can be expanded to more southern latitudes. Acknowledgments This researchwas supported by grants from the Appalachian Regional Commission, USDA– Cooperative State Research, SUNYResearch Initiative and the Empire State Development Fund to the senior author. Amultitude of SUNYCobleskill Fisheries andAquaculture students assistedwith this project. References Bernatchez, L., L. Glemet, C.C. Wilson, and R.G. Danzmann. 1995. 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