Date of Award
1-1-2025
Document Type
Dissertation
Degree Name
Ph.D. in Biological Science
First Advisor
Glenn R. Parsons
Second Advisor
Richard Buccholz
Third Advisor
Jan Hoover
School
University of Mississippi
Relational Format
dissertation/thesis
Abstract
The introduction of invasive bighead carp (Hypophthalmichthys nobilis) into the Pearl and Pascagoula River systems via the Bonnet Carré Spillway during flood control operations poses a significant threat to these unique ecosystems. This dissertation's experiments investigated the role of salinity in limiting bighead carp dispersal, demonstrating that brackish waters do not necessarily restrict their range as previously assumed. While bighead carp exhibited no significant impairment in swimming performance in salinities at or below 5 ppt, acute and chronic exposure to salinities at 15 ppt proved lethal within 50 hours, representing a critical salinity threshold. Despite mortality at elevated salinities, the potential for dispersal remains at lower salinities, as tidal fluctuations and river currents can facilitate movement regardless of swimming ability. Physiological response to salinity stress included increased gill beat frequency without changes in oxygen consumption, suggesting a compensatory shift towards anaerobic metabolism. The findings demonstrate that bighead carp can readily disperse throughout the Lake Pontchartrain basin and Mississippi Sound during flood events, enabling colonization of the Pearl River- approximately 80 km from the spillway outfall. These results underscore the complex relationship between salinity, flood events, and bighead carp dispersal, highlighting the need for refined range suitability maps and the exploration of salinity management strategies to mitigate the spread of this invasive species.
Recommended Citation
Katzenmeyer, Alan, "Salinity Tolerance of Bighead Carp and its Implications for Dispersal in the Lake Pontchartrain Ecosystem" (2025). Electronic Theses and Dissertations. 3309.
https://egrove.olemiss.edu/etd/3309