Date on Honors Thesis

Winter 12-10-2022


Fishers and Aquatic Biology


Bigheaded carp have spread rampantly throughout the Mississippi watershed and continue to spread by navigating through rivers, locks, and dams. The long-term effects these species will have on our ecosystems and natural resources is unknown. Their movements, behavior, and general seasonal patterns are well studied within rivers. However, their movements and behavior within reservoirs is poorly understood due to their initial numbers within reservoirs being lower than in rivers. To address this gap, I investigated the distribution and movement rates of Silver Carp within two reservoirs, Kentucky Reservoir and Barkley Reservoir, and possible correlative variables, including wind, temperature, residency, sex, and relative exposure index. I hypothesized that wind would have the greatest influence on Silver Carp movement rates and location, thru its effect on the distribution and abundance of food resources. Over 13 months, I collected movement rates on 30 individual Silver Carp; twenty-two of these Silver Carp were tracked for 24-hours. To my knowledge, these 24-hour tracking data are the first to be collected for this species within a reservoir. I determined that Silver Carp movement rates increased in waters of warmer temperatures (F1,28 = 6.8, p = 0.01, N = 30). Within Barkley Reservoir, swim rates did increase with mean wind speed (F1,4 = 12.5, p = 0.02, R2 = 0.76). However, this result will need further conformation, due to my low sample size (n = 6) within Barkley Reservoir, and no significant differences detected within Kentucky Reservoir. Data collected from the Hancock Biological Station confirms seasonal variation of phytoplankton but is distributed evenly among macrohabitats. It is possible Silver Carp are swimming at random considering their food source is abundant and evenly distributed.