Concordia University
Ph.D. candidate
Supervisor: Dylan Fraser
Start: 2019-09-01
End: 2024-03-31
Personal page

Project

Variation in effects of climate change on salmonid productivity: extent, scale, and underlying mechanisms
In my dissertation, I aim to explore how fine-scale intraspecific variation in phenotypes, demographics and their combined ecological effects on community and ecosystem dynamics will mediate population responses to future climate change in salmonid fishes. In Chapter 1, I conducted a global-scale meta-analysis to examine how observed effects of temperature and precipitation on salmonid productivity from 156 studies of 23 species were related to spatial, temporal, and biological variation among populations. In Chapters 2-4, I focused on local-scale variation in responses to climate change among wild populations of brook trout (Salvelinus fontinalis) in Cape Race (Newfoundland, Canada). Specifically in Chapter 2, I analyzed mark-recapture data from eleven brook trout populations in Cape Race from 2010-2022 in order to quantify asynchrony in abundance, somatic growth rates, and demographic relationships among populations. In Chapter 3, I collected and analyzed stream temperature data from 2012-2021 in order to describe thermal regimes experienced by ten Cape Race brook trout populations, then explored how temperature variation influenced phenology, growth and exposure to warming among populations. Finally, in Chapter 4, I combined my findings from Chapters 2 and 3 with previous results from common garden experiments and transplant studies in Cape Race brook trout in order to build eco-genetic models that simulated the effects of climate warming from 2001-2100 on demography and life history evolution in eight populations.

Keywords

population dynamics, Demographics, Global change biology

Publications

1- Effects of climate on salmonid productivity: A global meta‐analysis across freshwater ecosystems
Gallagher, Brian K., Sarah Geargeoura, Dylan J. Fraser
2022 Global Change Biology

2- Ecological carryover effects associated with partial migration in white perch (Morone americana) within the Hudson River Estuary
Gallagher, Brian K., Philip M. Piccoli, David H. Secor
2018 Estuarine, Coastal and Shelf Science

3- Intensified environmental and density-dependent regulation of white perch recruitment after an ecosystem shift in the Hudson River Estuary
Gallagher, Brian K., David H. Secor
2018 Canadian Journal of Fisheries and Aquatic Sciences

4- Factors Influencing Daily Growth in Young-of-the-Year Winter Flounder along an Urban Gradient Revealed Using Hierarchical Linear Models
Gallagher, Brian K., Lyndie A. Hice, Anne E. McElroy, Robert M. Cerrato, Michael G. Frisk
2015 Marine and Coastal Fisheries

5- Microgeographic variation in demography and thermal regimes stabilize regional abundance of a widespread freshwater fish
Gallagher, Brian K., Dylan J. Fraser
2023 Ecological Applications

6- Stream groundwater inputs generate fine‐scale variation in brook trout phenology and growth across a warming landscape
Gallagher, Brian K., Dylan J. Fraser
2023 Freshwater Biology