Tolerance of lake trout, Salvelinus namaycush (Walbaum), sac fry to dissolved gas supersaturation |
| |
| Authors: | W F KRISE R L HERMAN |
| |
| Institution: | National Fishery Research and Development Laboratory, U.S. Fish and Wildlife Service, Wellsboro, Pennsylvania, USA;National Fish Health Research Laboratory, U.S. Fish and Wildlife Service, Kearneysville, WV, USA |
| |
| Abstract: | Abstract. The tolerance of sac fry of lake trout, Salvelinus namaycush (Walbaum), to the acute effects of gas supersaturation, from hatching to swim-up, was tested using six gas levels, ranging from ΔP 8 to 148. Although many fish were moribund by the time the yolk was nearly absorbed, mortality during the 40-day study was negligible; survival to swim-up was 96–99%, including 99% survival at ΔP 148. Of fish examined at ΔP 42, 40% showed bubble formation around the rim of the eye. Signs of trauma were greatest at ΔP 119 and 148, and included intestinal bubbles, a distended abdomen, and bubbles around the eye, in the mouth and in jaw tissues. |
| |
| Keywords: | |
|
|
