Conservation Genomics: Integrating Evolutionary Theory into Fisheries Management

Abstract

Anthropogenic activities have caused the decay of biological diversity and widespread changes in biodiversity’s distribution by altering dispersal pathways and reducing wild population sizes. Genetic variation (i.e., the biodiversity occurring within species) can be analyzed to understand the negative effects of inbreeding and reduced genetic diversity on individual fitness, population adaptive capacity, and species long-term persistence. Therefore, genetic analyses represent a powerful tool to guide proactive management practices. The goal of this thesis is to connect genetic research to conservation practices to reveal insights on the evolutionary trajectory and the establishment and geographical spread of wild populations in novel environments. This dissertation consists of seven chapters divided into two major themes. Chapters two and three focus on identifying opportunities to improve the utilization of genetic information for developing conservation interventions. Specifically, I investigated whether we found support for the existence of a “gap” between conservation genetic research and conservation practices in the literature (chapter 2) and among experts (chapter 3). I found that the literature reflects conservation priorities and both scientists and practitioners view genetic information as useful for conservation, implying that the “gap” concept is not appropriate to describe the space between genetic research and conservation practices. The following three chapters are case studies focused on the genetic consequences of introductions (chapters 4, 5) and range expansion (chapters 5, 6) for invasiveness. I focused on Tench (Tinca tinca), a widespread species in decline in its native range (Eurasia) and considered invasive in many non-native locations (e.g. North America, Oceania). These characteristics make Tench an ideal candidate to study not only the factors influencing the ability of populations to retain genetic diversity following founder events and during range expansions, but also leverage genetic analyses to provide context-specific management recommendations. Using reduced-representation sequencing approaches (e.g. RADseq, GBS) and simulations, I highlight the importance of historical and contemporary processes for the retention of genetic diversity, with implications for the ability of populations to respond to inbreeding and adapt to novel environments. Collectively, these studies highlight that genetic data can reveal information on the demographic history of wild populations, help improve predictions related to their future evolutionary trajectories, and improve management.