By J.S. Alabaster
Water Research, Volume 1, Issue 10, October 1967, Pages 717-730, ISSN 0043-1354, DOI: 10.1016/0043-1354(67)90074-7.

The survival of salmon and seatrout smolts, on sudden exposure to increased temperature, has been measured under field and laboratory conditions in both fresh and salt water. Smolts are more sensitive than parr when tested in fresh water, particularly if no special care is taken to acclimate the fish to the test conditions beforehand. Salmon smolts are most sensitive to an increase in temperature when exposed simultaneously to change from fresh to sea water, though the effect is much less even after only 7 hr prior acclimation to sea water; they are most resistant when tested in 30 per cent sea water.

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