Physiological disturbances and overwinter mortality of largemouth bass from different latitudes.
Thermal conditions associated with winter can influence the distribution of a species. Because winter severity varies along latitudes, populations of temperate fish located along a latitudinal gradient may display variation in both sublethal and lethal responses to cold stressors. Sublethal physiological disturbances were quantified in age 1 largemouth bass (Micropterus salmoides) from populations originating from Alabama and Illinois but raised in a common environment. Fish were exposed to 6 h of rapid cold shock from 20° to 8°C (controls were held at 20°C) and then sampled for white muscle, whole blood, and plasma. After cold shock, glucose concentrations were elevated in Alabama but not Illinois fish. Sodium was lower and chloride was higher in Alabama largemouth bass, but fish from Illinois had a greater propensity for potassium loss during cold shock. In Illinois ponds, Alabama largemouth bass exhibited lower overwinter survival (adult: 10%; age 0: 22%) than did those from Illinois (adult: 80%; age 0: 82%). Latitudinal variation in physiological responses to cold stressors may therefore influence overwinter survival of largemouth bass and the ability of a fish species to exist over large geographic areas.
Kaskaskia Biological Station, Illinois Natural History Survey, University of Illinois at Urbana-Champaign, 1235 CR 1000N, Sullivan, Illinois 61951; 2Department of Natural Resources and Environmental Sciences, University of Illinois at Urbana-Champaign, W401-C Turner Hall, 1102 South Goodwin Avenue, Urbana, Illinois 61801.
Matthew M
MM
VanLandeghem
Curtis P
CP
Wagner
David H
DH
Wahl
Cory D
CD
Suski
D000222:Adaptation, Physiological / Q000502:physiology*; D000407:Alabama; D000818:Animals; D001492:Bass / Q000097:blood / Q000502:physiology*; D001786:Blood Glucose / Q000032:analysis; D016009:Chi-Square Distribution; D002712:Chlorides / Q000097:blood; D003080:Cold Temperature / Q000009:adverse effects*; D006400:Hematocrit; D006454:Hemoglobins / Q000032:analysis; D007087:Illinois; D018482:Muscle, Skeletal / Q000502:physiology; D011188:Potassium / Q000097:blood; D012621:Seasons; D012964:Sodium / Q000097:blood
D001786:Blood Glucose; D002712:Chlorides; D006454:Hemoglobins; D012964:Sodium; D011188:Potassium