Bighead Carp effects on the growth, abundance, and survival of larval Bluegill

Asian Carp;Bluegill;Competition;Larval;Growth;Recruitment

Fletcher, Cameron Morris ; Chick, John H., ; ,Casper, Andrew F., ; ,Yannarell, Anthony C. ; Wahl ; Dave H

关键词: Asian Carp;    Bluegill;    Competition;    Larval;    Growth;    Recruitment;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/97435/FLETCHER-THESIS-2017.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Bighead Carp (Hypophthalmichthys nobilis) are an invasive planktivore, native to Asia, that have established successful populations in the Mississippi and Illinois River systems after their unintentional introduction in the 1980’s.Their ability to efficiently consume zooplankton, has generated enormous concern for the native fishes in these ecosystems and those in connected water bodies yet to be invaded.Current research on their competitive interactions with native fishes, especially facultative planktivores, is not well documented and inconsistent.Furthermore, inquiries into their effect on the larval stages of native fishes have yet to be made.The objective of my thesis was to test for competitive interactions between Bighead Carp and a facultative planktivore as they relate to larval growth, abundance, and survival.Moreover, I aimed to compare the competitive effects of Bighead Carp to those of a native planktivore.I conducted two experiments at different spatial scales involving Bighead Carp, Golden Shiners (Notemigonus crysoleucas), and larval Bluegill (Lepomis macrochirus).My first experiment involved investigating the growth of larval Bluegill at varying densities of either Bighead Carp or Golden Shiners in a controlled mesocosm setting.The results of this experiment inconsistently suggested that Bighead Carp reduce the growth of larval Bluegill to a greater extent than Golden Shiners.My second experiment was at a larger scale in 0.4 hectare ponds and aimed to examine the recruitment success of Bluegill when either Bighead Carp or Golden Shiners were present.This experiment consistently showed that Bighead Carp reduce the daily growth rate, and ultimately recruitment efficiency, of larval Bluegill to a greater extent than Golden Shiners.Effects observed in both studies correlated with greater decreases in zooplankton by Bighead Carp compared to Golden Shiners.These results begin to indicate that an invasive planktivore may negatively affect the growth of larval Bluegill, and other native fishes with similar life-histories, to a greater extent than a native planktivore.My results help to further understand the effects Asian Carp are having on the Illinois and Mississippi River systems and provide insight into their potential impacts on aquatic systems yet to be invaded.