A molecular-telemetric approach to Atlantic salmon reintroductions: how human intervention can promote the establishment of new populations

• Main Author: Harbicht, Andrew B.
• Format: Thesis
• Language: English
• Published: 2017
• Subjects: Atlantic salmon
• Online Access: https://spectrum.library.concordia.ca/id/eprint/983392/; https://spectrum.library.concordia.ca/id/eprint/983392/2/Harbicht_PhD_S2018.pdf

With increases to the number of species and populations impacted by human activities, the need for human involvement in their maintenance and/or conservation has grown in turn. This involvement increasingly takes the form of re-introductions, relocations, or supplementation of populations in decline or that have been lost. As a result, reintroduction biology has become a quickly growing field of research that attempts to answer the many questions related to reintroductions and translocations. When and how to release individuals into the wild, at what age should they be released, and in what situations is the introduction of new individuals sufficient to establish new populations. To advance our understanding of species reintroductions and address some of these questions in situ, adaptive management experiments and new techniques were developed for the Atlantic salmon reintroduction program in the Lake Champlain basin. These experiments assessed the suitability of commonly used methods in salmonid reintroduction and supplementation for re-establishing or strengthening self-sustaining populations and meta-population structure through direct comparisons of long-term survival, spawning returns, and dispersal rates. Concurrently, to address how changes in the species composition of Lake Champlain have affected the ability of reintroduced salmon to establish themselves, radio telemetry was employed to monitor spawning migrations through a challenging, high velocity section of the Boquet River, a tributary to Lake Champlain. In doing so, new, transferrable radio telemetric techniques for continuous fine scale monitoring were developed. In comparing alternative rearing/release techniques to the standard method of producing large 1+ parr through the use of elevated rearing temperatures, several significant trends were apparent. First, while fry (age 0+) are commonly held to exhibit reduced survival to adulthood relative to 1+ parr, once natural mortality during the first year was accounted for, fry returns exceeded those ...