Fish standard length of Gobius incognitus individuals used for the mutual transplant between an ambient (∼380 μatm) and high (∼850 μatm) CO2 site off a volcanic CO2 vent in Vulcano island, Italy

Fish standard length (cm) of Gobius incognitus individuals used for a mutual transplant experiment (Ambient-Ambient, High CO2-Ambient, High CO2-High CO2, Ambient-High CO2). Standard length was measured from digital photographs, using a ruler as a reference with the ImageJ software.