Zebadiah Woiak Richard A. Erickson Jon Amberg Mark P. Gaikowski Aaron R. Cupp 2017 <p id="Par1" class="Para">Resource managers need effective tools to control invasive fish populations. In this study, we tested under-ice carbon dioxide (CO₂) injection as a novel piscicide method for non-native Silver Carp (<i class="EmphasisTypeItalic ">Hypophthalmichthys molitrix</i>), Bighead Carp (<i class="EmphasisTypeItalic ">Hypophthalmichthys nobilis</i>), Grass Carp (<i class="EmphasisTypeItalic ">Ctenopharyngodon idella</i>), Common Carp (<i class="EmphasisTypeItalic ">Cyprinus carpio</i>) and native Bigmouth Buffalo (<i class="EmphasisTypeItalic ">Ictiobus cyprinellus</i>). Fish were held overwinter in nine outdoor ponds (0.04&nbsp;ha surface area; 340,000 L volume) treated with no CO₂ (control), 43.5–44.0&nbsp;kg CO₂ (low treatment), and 87.5–88.5&nbsp;kg CO₂ (high treatment). Ponds were harvested immediately after ice-out to assess survival and condition. Resulting survival in low (mean&nbsp;=&nbsp;32%) and high (mean&nbsp;=&nbsp;5%) CO₂-treated ponds was significantly lower than untreated control ponds (mean&nbsp;=&nbsp;84%). Lethal efficacy varied across species with no Bighead Carp, Silver Carp, or Bigmouth Buffalo surviving the high CO₂ treatment. External infections were observed more frequently after CO₂ treatments (means&nbsp;=&nbsp;49–67%) relative to untreated ponds (mean&nbsp;=&nbsp;2%), suggesting a secondary mechanism for poor survival. This study demonstrates that CO₂ can be used as a lethal control for invasive fishes, but effectiveness may vary by species and CO₂concentration.</p> application/pdf 10.1007/s10530-017-1462-9 en Springer Carbon dioxide as an under-ice lethal control for invasive fishes article