Bigheaded carps are non-native invasive fishes that have quickly become the most abundant fishes in many portions of the Midwestern United States. While the spread of bigheaded carps into the Great Lakes is currently impeded by three electrified barriers, these fish have the potential to negatively impact the Great Lakes ecosystem if this barrier is breached, and these barriers may be particularly vulnerable to the passage of small fishes. As such, novel barrier technologies would provide an additional mechanism to prevent bigheaded carps from invading the Great Lakes, and provide much needed redundancy to the current electric barrier. The current study used a combination of molecular and behavioral experiments to determine the effectiveness of carbon dioxide as a chemical deterrent for larval and juvenile fishes, with an emphasis on bigheaded carps. Juvenile silver carp (Hypophthalmichthys molitrix), bighead carp (H. nobilis), bluegill (Lepomis macrochirus) and largemouth bass (Micropterus salmoides) showed avoidance of elevated CO2 environments at approximately 200 mg/L. Additionally, exposure to 120 mg/L CO2 resulted in the induction of hsp70 mRNA in 8 days old silver carp fry, while gill c-fos transcripts increased following hypercarbia exposure in all juvenile species examined. Together, our results show that CO2 has potential to deter the movement of larval and juvenile fishes.
Bibliographical noteFunding Information:
This work was supported by the Illinois Department of Natural Resources, through funds provided by the USEPA’s Great Lakes Restoration Initiative. Partial funding was also provided by the United States Geological Survey and by the United States Fish and Wildlife Service (USFWS) Federal Aid in Sport Fish Restoration Project F-69-R. Steve Kahrs and Pete Kahrs provided valuable help supplying larval bigheaded carps. We would like to thank James Luoma, Mark Gaikowski, along with the other biologists at UMESC, for providing valuable help with fish collection and juvenile bigheaded carps husbandry. David Sutter, Dan Kates, Thomas Kates, Will Cejtin, and Adam Wright provided field and laboratory assistance. All work performed in this study conformed to guidelines established by the Institutional Animal Care and Use Committee (IACUC) of the University of Illinois (Protocol # 13123).
© 2015, Springer International Publishing Switzerland.
- Bigheaded carps