Thermoadaptation Characteristics of European River Lamprey Lampetra fluviatilis Smolts

Thermoadaptation characteristics of smolts of European river lamprey Lampetra fluviatilis are studied in experimental conditions for the first time. The final preferred temperature in the smolts preliminary acclimated to water temperature of 9 is 15.3 degrees C. The value of sublethal temperature determined by the method of critical thermal maximum at a 9 degrees C/h temperature increase rate is 29.0 degrees C, while that of the upper lethal temperature is 30.8 degrees C. The values of the final selected and upper lethal temperatures in river lamprey smolts are close to those in salmonids and coregonids.