JDJCSET | Watershed Studies Institute Research Symposium
Important Factors Affecting Larval Fish Phenology in Kentucky Lake
Academic Level at Time of Presentation
Senior
Major
Fisheries/Aquatic Biology
Minor
None
List all Project Mentors & Advisor(s)
Michael B Flinn, PhD
Presentation Format
Oral Presentation
Abstract/Description
A working knowledge of larval fish phenology in dynamic systems like large-river reservoirs is useful for understanding community dynamics and responses to perturbations such as invasive species. The timing of interactions between environmental factors and resources can affect the success and recruitment of sensitive larval stages. The goal of this study is to determine the effects of environmental and biological factors on the phenology of larval fish in Kentucky Lake. We sampled the southern 30 km of Kentucky Lake from April-May of 2014, 2015, and 2016 to quantify the ichthyoplankton community. Samples were collected using larval pushnets (net=0.5m^2, mesh=1mm), and fish were enumerated and identified to family. Results suggest that assemblages were highly variable with few similarities among years. However, Clupeidae was consistently the dominant taxa every year. Additionally, the time of first detection for the majority of taxa observed occurred during the same period (April 17–April 25) in 2014, 2015, and 2016. Some environmental variables (water temperature and elevation) were consistent across years, while others differ. We believe this consistency in temperature and surface water elevation likely explains why the time of first detection for the majority of the sampled taxa fall within the same 9-day period. While detection for most taxa is consistent across years, peak densities vary. The addition of larval fish phenology data to the long-term environmental dataset from Kentucky Lake provides an important indicator of reservoir dynamics and can potentially act as an early detection system for changes in community structure due to disturbance.
Affiliations
Watershed Research Institute
Important Factors Affecting Larval Fish Phenology in Kentucky Lake
A working knowledge of larval fish phenology in dynamic systems like large-river reservoirs is useful for understanding community dynamics and responses to perturbations such as invasive species. The timing of interactions between environmental factors and resources can affect the success and recruitment of sensitive larval stages. The goal of this study is to determine the effects of environmental and biological factors on the phenology of larval fish in Kentucky Lake. We sampled the southern 30 km of Kentucky Lake from April-May of 2014, 2015, and 2016 to quantify the ichthyoplankton community. Samples were collected using larval pushnets (net=0.5m^2, mesh=1mm), and fish were enumerated and identified to family. Results suggest that assemblages were highly variable with few similarities among years. However, Clupeidae was consistently the dominant taxa every year. Additionally, the time of first detection for the majority of taxa observed occurred during the same period (April 17–April 25) in 2014, 2015, and 2016. Some environmental variables (water temperature and elevation) were consistent across years, while others differ. We believe this consistency in temperature and surface water elevation likely explains why the time of first detection for the majority of the sampled taxa fall within the same 9-day period. While detection for most taxa is consistent across years, peak densities vary. The addition of larval fish phenology data to the long-term environmental dataset from Kentucky Lake provides an important indicator of reservoir dynamics and can potentially act as an early detection system for changes in community structure due to disturbance.