Differential Movement Response of Silver Carp to Individual and Environmental Conditions in the Illinois and Wabash Rivers

Author

Taylor Mogavero, Southern Illinois University CarbondaleFollow

Date of Award

8-1-2023

Degree Name

Master of Science

Department

Zoology

First Advisor

Garvey, James

Abstract

Knowledge about the spatial dynamics of invasive species is essential to predict, restrict, and prevent their spread to new areas. Invasive Silver Carp (Hypophthalmichthys molitrix) populations are expanding on all fronts and are threatening to establish in the Laurentian Great Lakes. Understanding their movement patterns is vital to prevent their populations from spreading further and to improve management efficiency. This study looked at multiple factors to understand which have an influence on the movement of invasive Silver Carp in two different river systems. Chapter 1 examined the relationship between individual and environmental factors—including length, body condition, temperature, and discharge—and movement in invasive Silver Carp in the Illinois River. Several different movement metrics were examined—including range, upstream and downstream distance per detection, upstream and downstream movement rate, and total movement—to see if they were affected by any of these factors. Chapter 2 examined multiple morphological metrics—including geometric morphometrics, total length, caudal peduncle depth, and caudal fin aspect ratio—related to the movement of Silver Carp in the Wabash River to see if Silver Carp with similar movement have similar morphology. For both chapters, acoustic telemetry was used to track the movement of Silver Carp. For analysis, multiple generalized linear models were used. For Chapter 1, temperature and discharge were the most commonly included predictors across movement metrics. For Chapter 2, no morphological metrics were identified as predictors of movement. Quantifying the effects of individual and environmental factors can aid in the control and containment of this invasive species and may help to manage populations in at-risk environments. This study demonstrated that factors, like temperature and discharge, can be used to determine when individuals are more likely to expand the invasion front of Silver Carp in the Illinois and Wabash rivers. Which specific individuals are the largest threat to the invasion front can be predicted by individual factors like length, but not body shape.