Author Neema Tavakolian, 2021 research associate at IIASA
Lyndsie Wszola, a participant in the Summer Young Scientists Program (YSSP), is investigating how human interactions with warming freshwater systems have influenced the evolution of fish species through the lens of the North American walnut.
The effects of climate change have intensified in recent years, especially in our oceans, so human-based activities that contribute to it are now being taken more seriously. The warming of our oceans is truly worrying, many forget that freshwater systems are also affected and that this affects the growth and evolution of the species that inhabit them.
YSSP 2021 participant Lyndsie Wszola wants to explore changes in freshwater systems using modeling systems of man and nature at IIASA.
Growing up with the father of a conservation officer, Wszola is a second-generation conservative. Knowing that she wanted to enter this field from an early age, she realized that she must first engage in research and academia. Her main interest while studying at the University of Nebraska was the interaction between humans and wildlife.
Exploring the relationships between hunters and ring-necked pheasants, she discovered an affinity for quantitative research. This curiosity went even further after she discovered the literature on harvest-induced evolution and mathematical ecology specifically related to fish populations. Together, this initial desire to explore human-wildlife interactions and her newly discovered interest in mathematical ecology, led Wszola to take a closer look at North American freshwater systems and how we as humans affect its ecology. Her research is particularly concerned with studying the growth and evolutionary changes seen in the North American pitcher (Sander Vitreus) – a popular fish in Canada and the United States. The reason for its fame is its sweet taste as a freshwater fish and its status among anglers, which makes it both a commercial and recreational fishing species.
Walleye was chosen as the subject of Wszola’s research for many reasons. First, the nut is, like many fish, an ectotherm which means that their bodily processes and behavior are directly related to their body temperature, which in turn is directly related to the water temperature. Unlike other fish, however, there is already a lot of research and data on the relationship between growth and temperature. This information greatly facilitates the simulation of the eco-evolutionary dynamics of grain growth in the context of a human-initiated harvest in warm waters. Wszola will also work with very large data sets spanning multiple latitudes, from Ontario in Canada to Nebraska in the US. Data sets include up to six million fish, of which four million are fish.
“My goal is to model the effect of temperature on fish catch based on size. Due to their ectothermic nature, we can see changes in body size in annual harvests. As the water heats up, the walnut grows much faster. We also know that intensively caught fish often develop to mature in smaller sizes. Combined with the rise in temperature, this relationship between harvest and temperature-induced evolution can be fascinating, because we now have two sources working together to change the evolution of the growth of this fish, ”she explains.
Due to high temperatures, many natural resources are at stake, and some of the most sensitive are aquatic in nature. Such research is important because it allows us to look at our relationships with the environment so that we can react accordingly.
“I hope that my research will yield sufficiently fascinating results, so that from a practical point of view future fisheries policy can include climate change dynamics other than fish and human,” Wszola concludes.
Note: This article presents the views of the authors, not the views of the Nexus Blog or the International Institute for Applied Systems Analysis.