Non-Avoidance of Lethal Temperatures of the Introduced Round Goby, Neogobius melanostomus

The Round Goby Neogobius melanostomus, has been introduced and dispersed in North American waters, where it has adversely impacted native fishes. We must identify physical/chemical/biological parameters that will target the Round Goby but not have an adverse impact on native fishes if we are to control its further dispersal. Temperature is a quantifiable parameter influencing both the behavior and survival of fishes and may provide insights to predict their dispersal and survival. The temperature preference of the Round Goby was investigated in a horizontal thermal gradient. Fish were collected from LeBoeuf in Erie County, Pennsylvania, in August 2024. Round Gobies were acclimated to 5, 10, 15, 20, and 25 °C. The relationship between preference temperature and acclimation temperature was best explained by p = (0.91a) + 4.2. (R2 = 0.83), where p = preferred temperature and a = acclimation temperature. When acclimated to 25 °C, three fish swam into water at 30 °C and immediately lost equilibrium. The final preferred temperature was estimated to be 26.5 °C. The difference between preferred temperature and acclimation temperature for most temperate fishes decreases as acclimation temperature increases. This trend was not observed for the Round Goby.