Carbon dioxide-induced mortality of four species of North American fishes

There is growing interest in the use of carbon dioxide (CO2) as a management tool for controlling invasive fishes. However, there is limited published data on susceptibility of many commonly encountered species to elevated CO2 concentrations. Our objective was to estimate the 24-h LC50 and LC95 of four fishes (Rainbow Trout Oncorhynchus mykiss, Common Carp Cyprinus Carpio, Channel Catfish Ictalurus punctatus, and Westslope Cutthroat Trout Oncorhynchus clarkii lewisi). In the laboratory, we exposed fingerlings to a range of levels of CO2 for 24-h in unpressurized, flow-through tanks. A Bayesian hierarchical model was developed to estimate the dose response relationship for each species of fish with associated uncertainty, and posterior draws were obtained for the 24-h LC50 and LC95 values for each species. The 24-h LC50 (95% posterior interval) values were estimated as 150.7 (138.2 to 166.0) mg CO2/L for Rainbow Trout, 193.5 (177.6 to 212.0) mg CO2/L for Westslope Cutthroat Trout, 340.4 (308.7 to 375.4) mg CO2/L for Common Carp, and 352.2 (313.9 to 391.1) mg CO2/L for Channel Catfish. The 24-h LC95 (95% posterior interval) values were estimated as 190.6 (177.2 to 207.8) mg CO2/L for Rainbow Trout, 245.0 (222.2 to 272.2) mg CO2/L for Westslope Cutthroat Trout, 422.5 (374.7 to 474.5) mg CO2/L for Common Carp, and 434.2 (377.2 to 492.2) mg CO2/L for Channel Catfish. We observed complete mortality at 275 mg CO2/L (38,671.67 µatm), 225 mg CO2/L (30,710.74 µatm), and 495 mg CO2/L (65,707.70 µatm (CC); 77,212.55 µatm (CF)) for Westslope Cutthroat Trout, Rainbow Trout, and both Common Carp and Channel Catfish, respectively. Although the experimental findings show strong relationships between increased CO2 concentration and higher mortality, additional work is needed to assess the efficacy and feasibility of a CO2 application in a field setting.

[
  "010:12"
]

[
  "geospatial"
]