In collaboration with researchers at Concordia University, Montreal, we designed a common-garden experiment where the developmental and genetic differences between dwarf and anadromous Atlantic salmon can be studied in controlled environmental conditions. Through fieldwork during the breeding season of the dwarf salmon we gained new insight into their previously unknown reproductive ecology and behavior. Contrary to previous research that indicated a maximum fecundity of ~30 eggs per dwarf salmon female, our field-observations indicate that the number of ripe eggs may vary between 1-28 depending on the female. This suggests that the dwarf salmon females may lay as few as a single egg at a time when spawning. Because breeding may happen with different males each time, these observations indicate that dwarf salmon populations may harbor more genetic diversity that would be expected given their extremely small population sizes. Furthermore, we field-collected gametes from dwarf salmon from two small streams in Cape Race, Newfoundland, using electrofishing and transported the gametes to Concordia University Aquatic Facilities. In addition, we collected gametes from anadromous Atlantic salmon that were captured from the Saint-Mary’s River in Nova Scotia, Canada, and raised at a Canadian governmental hatchery. The gametes were used to establish populations of dwarf and anadromous Atlantic salmon, and their F1 hybrids, at common environmental conditions at Concordia University. These populations, which have been established following a breeding design allowing the study of their genetic characteristics, allows for unique experimental procedures to be performed that will reveal the molecular mechanisms of allometry in salmon reproductive development. We further established cell cultures of a gonad cell line from rainbow trout that will allow for the in vivo validation of the function of the genetic mechanisms discovered in controlling cellular development such as cell size and proliferation.
