Challenges to Trout Conservation
Sorry, folks. I'm copping out this week. I'm on the heels of another conference, and the there's a tornado of activity as I try to wrap up loose ends at the office before embarking on an eight-state, 12-day tour of the mid-west. Badlands, Rushmore, Bozeman...quick conference in Yellowstone....Jackson Hole, Salt Lake. I live the silver spoon grad school life.
In all seriousness, my advisor is more than generous with his allocation of resources and supports me making these trips. Not all advisors give their students the freedom to attend expensive conferences. But, I also help my cause and do some of my own fundraising. A few days ago I was honored to be named a recipient of the 2017 Marty Seldon Scholarship to offset some travel costs to the Wild Trout Symposium in Yellowstone. The application was fairly straightforward- an essay describing my research, involvement in professional fisheries organizations, and what I feel are the most pressing issues in trout conservation.
Below is my submission. For many of you seasoned readers, you already know the spiel. For some of you newer readers- sit back, learn a little about me, my research, and what I'm fighting for.
Conservation of wild trout populations is met with a myriad of challenges with none more pervasive than climate change. Look no further than the northern-receding margins of the eastern brook trout’s range, collapse of cutthroat trout populations in the Rockies, and declines of European brown trout to find evidence that climate change is threatening salmonids worldwide.
Managing coldwater fisheries under climate change is a complex problem of scale. Large-scale changes to stream temperature, flow regimes, and habitat availability transcend watershed and political boundaries, often making management logistically and financially unfeasible. Yet, there are also small-scale changes to species interactions, population vital rates, and individual fish physiologies that are not only difficult to manage, but also remain poorly understood. Together, the effect that climate change has on trout populations within and across scales produces unanticipated, nonlinear patterns and dynamics that reduce our ability to predict future outcomes of habitat loss and effectively manage trout populations.
The efficacy of present-day management objectives, which largely focus on increasing population sizes and habitat availability, will only continue to decline as climate change outpaces restoration efforts. Accordingly, management must become more forward thinking and include conservation of the fine-scale properties that naturally increase population resistance and resilience to habitat loss. To accomplish this goal, a better understanding of individual variation is needed to answer questions such as: why are some populations and individuals more fit than others, are there specific genes that lead to higher thermal tolerance, why do fish behave differently from one another, and is individual variation important for population survival?
These are just some of the questions I am addressing in my dissertation research at Pennsylvania State University in the lab of Dr. Tyler Wagner. Specifically, I am merging the fields of genetics, behavior, and population ecology in a series of field and laboratory studies to investigate the adaptive significance of intraspecific variation in native brook trout populations in Pennsylvania.
At a molecular level, I am studying population genetic structure to identify spatial patterns in genetic diversity. While previous studies suggest that brook trout populations readily isolate at small spatial scales, my research suggests that genetic connectivity and diversity remain high near mainstem river corridors as compared to headwater populations. This suggests that the processes that maintain metapopulation dynamics differ across the species’ range. Further, because genetic diversity is correlated to adaptive capacity and resiliency, the location of a population within a stream network could predict evolutionary potential and extinction risk.
I am also completing one of the first studies of gene expression in wild trout populations to quantify expression patterns of heat shock protein 47 (HSP47), a common indicator of thermal stress in fishes. In total, I evaluated gene expression for nearly 700 fish using non-lethal gill and blood samples collected every 1-3 months for over a year. Preliminary results suggest that HSP47 expression is highest in early spring, and nearly absent in summer when stream temperature is warmest. This suggests that brook trout begin expressing heat shock proteins in response to mild increases in stream temperature, and that there is a limit to how much HSP47 can be produced before gene expression stops. Ultimately, these results could indicate a limited scope for adaptation and plasticity in stress protein production.
To determine how intraspecific genetic and behavioral variation influence population structure and survival, I completed a multi-season telemetry study on 180 wild brook trout distributed across four tributaries to Loyalsock Creek, Pennsylvania. From this work, I documented significant individual variation in behavior, including some fish that completed large-scale, post-spawn movements to overwinter in mainstem Loyalsock Creek; a system largely considered unsuitable for brook trout prior to my study. Taken together, the observed zero-centered leptokurtic distribution in movement and patterns in population genetics describe above suggest there may be multiple life history strategies in some brook trout populations, including some highly migratory individuals that disproportionately increase genetic connectivity among populations. In the future, I will complete a genome-wide association study to identify specific genes that correlate to different movement patterns.
In the lab, I am completing several studies to determine whether inter-individual differences in behavior can be explained by fish personality. While it is understood that personality can modulate growth, reproduction, and mortality, the ecological and evolutionary significance of personality has not been rigorously explored in any taxa. I determined that boldness, the most studied personality trait in fish, reduces spatial learning ability. This finding suggests that phenotype influences learning and memory processes, and could explain differences in habitat use and movement among individual trout. I am currently conducting another lab study to determine how boldness influences the ability of fish to compete for resources at different stream temperatures. I hypothesize that the higher metabolic demand of bold fish will decrease their success at defending resources at higher temperatures.
Though I hope to increase the efficacy of trout management with novel research objectives, I am equally passionate about improving conservation through communication. I am the first author of seven peer-reviewed manuscripts ranging in topics from long-term stream habitat management to social learning in trout. I have also given over 20 presentations at state and national conferences, many of which receiving best paper awards.
In addition to professional communication, I continually seek opportunities to interact with the public through outreach and education. I am particularly passionate about introducing prospective biologists to stream ecology within the framework of professional service. For example, my election to President (Virginia Tech Chapter), Membership Chair (Virginia Chapter), and Social Media Coordinator (National Chapter) of AFS has afforded me the opportunity to lead educational programs and workshops for students and professionals and increase AFS participation at all levels. I also served as the Southern Division AFS Newsletter Editor that represents 15 states and am currently a member of the Virginia AFS Outreach Committee. My leadership in AFS has been recognized with several state and national awards.
Having realized my passion for science communication, I extended my outreach efforts beyond AFS programs and founded www.thetroutlook.com, a website specifically devoted to improving public access and understanding to information related to coldwater stream and trout ecology. Through weekly updates, I provide information about my research and introduce the readership to topical issues in fisheries conservation. This website has been viewed over 70,000 (side note- this number is getting closer to 100,000 now) times by an international audience, is regularly used as a teaching tool in K-12 schools, and has attracted attention from community groups and universities. Because of this media presence, within the last year I was invited to give nearly 20 seminars to several universities and to the Pennsylvania Council and local chapters of Trout Unlimited.
My passions for research, outreach, and education underlie my desire to pursue a career in academia. I believe that the persistence of natural resources will depend on inspired, well-trained scientists who can think creatively and critically to solve some of the world’s most pressing problems. I want to enable the next generation of problem solvers by fostering in them a life-long curiosity for ecological research. This is a goal I have already started realizing as the lead advisor for seven undergraduate students at Penn State and Susquehanna universities completing independent research projects or internships.
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