Research

RIVER Mosaic Lab

We conduct applied ecology that integrates field-based investigations, laboratory analyses, and quantitative modeling to test ecological theory in human-altered ecosystems. Ecological theories guide our understanding of nature, shape hypothesis testing, and inform management, yet many are based on biased datasets from well-studied species or pristine environments. In human-altered or understudied systems, covering ~ 95% of Earth, their applicability is uncertain. Our work tests theories and addresses fundamental questions in connectivity, food web dynamics, and species interactions, with direct applications for conservation and management across spatial and temporal scales

Past and Ongoing Research

Ecosystem-based fisheries management of Lake Erie

Lake Erie is a highly managed and disturbed system with productive percid fisheries. Using structural equation modeling and machine learning, we identified causal pathways among food web components and abiotic drivers that lead to recruitment of fisheries species, and how these linkages changed over time. This project built on a stakeholder-developed qualitative conceptual model.

River theory and resource use of fish in the Upper Mississippi River System

Quantifying ecological patterns in large rivers is difficult for a variety of reasons, leading to little empirical evidence on how rivers function and how organisms interact with their environments. I am quantifying life-long, seasonal, and daily resource use of twelve native fishes in the Upper Mississippi River system (Mississippi River north of Cairo, IL and the Illinois River) using otolith microchemistry, stable isotopes, and diets. Combined with concurrent studies on vital rates (growth, mortality, and recruitment) and genetics, we aim to determine stock delineation, management needs, and the level of ecosystem functioning in this highly managed but ecologically poorly understood large river.

Streamlining natal origin assignment

Hard part microchemistry analyses are used to assign organisms like fish to a natal origin (birth place). These analyses rely on analyzing the chemical composition of metabolically inert aging structures such as fish otoliths using a mass spectrometer and laser (LA-ICPMS). Resulting data files are clunky and hard to work with, so I have created repeatable R scripts to streamline the data wrangling process. After data processing, organisms are assigned to a natal origin based on the aging structure's chemistry compared to water chemistry. In many instances, origin classifications rely on a lot of collected data that may not be available and are assigned through a long and not easily reproducible process. With the help of collaborators, including Dr. Jimena Golcher-Benavides, we are working to streamline the process of assigning organisms to natal origin by co-opting established tools in other areas of ecology.

Intra and inter individual variation in resource use

Organisms choose their resources based on availability and individual preferences, which leads to phenotypic plasticity or simply put that organisms choose different resource from one another. However, identifying the resources select across their lives is difficult because we cannot reliably recapture individual organisms. Using chronologically and integrated tissues like otoliths and eye lenses of fish, we can compare resource use among individuals and within an individual's lifetime. My former undergraduate mentee, Azareah Carson, used the eye lenses of bowfin and largemouth bass to compare their life-long resource use between and among individuals. The analyses and write-up of this research is ongoing. Highlight: she won an award for best poster presentation on this research at SIUC's student research symposium.

Vertebrate extinction risk

Earth is in the sixth mass extinction, which is the only extinction event caused by humans. Extinctions are generally not random, and it was believed that predatory animals had the highest extinction risk, but no empirical evidence existed for this claim. We quantified the extinction risk of all mammals, birds, and reptiles and found that herbivores from each group consistently had highest extinction risk and extinctions at both global and regional scales.

Lake sturgeon conservation and aquaculture

Lake sturgeon are a long-lived and culturally important species in the Midwest United States. They have much lower population sizes due to overharvest, pollution, and habitat degradation, so conservation efforts have attempted to rebuild their populations as well as understand their ecology to improve management. I was part of the great lakes sturgeon long-term research project through Michigan State University and the Michigan DNR. I conducted a few research projects that involved quantifying growth of reared larvae fed different diets, gut microbiota composition during diet shifts, and predator-prey experiments to understand how predators respond to lake sturgeon and other prey.

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