Optimizing strategies to hydraulically plant Atlantic salmon eggs based on fry dispersal patterns
June 2018 - December 2021
The Gulf of Maine Distinct Population Segment of Atlantic salmon has suffered from habitat loss and exploitation over the last century. Hatchery supplementation has unquestionably prevented the extirpation of the species over the last decades. Stocking older life history stages minimizes early life history mortality, but does so at a cost of limiting exposure to a natural freshwater environment. Egg planting is a process by which fertilized eggs from the hatchery are injected into the gravel in the fall replicates the natural spawning process in streams and provides a natural experience which can be important for adaptation. This methodology has been used experimentally within the region, but significant uncertainties exist in developing the effective implementation of this method at a greater scale. Specifically, the habitat dependent distribution of juveniles after emergence from the gravel would provide information necessary to apply the technique to meet conservation hatchery goals with respect to fall parr densities. We propose to characterize the dispersal pattern of egg planted Atlantic salmon as a function of habitat and use these data to construct a GIS based tool to inform stocking. This work, if successful, can help to optimize the application of egg planting at a management level.