When hatchery-reared and wild landlocked Atlantic salmon (Salmo salar) parr of the same age and size were permitted to compete for social dominance and for food in aquaria, twice as many hatchery salmon attained dominance as wild salmon. Dominant hatchery salmon also showed a higher intensity of aggressiveness than dominant wild salmon, displaying a higher and more variable mean nipping rate. Socially dominant salmon ate more food per fish than subordinates, but there were no statistically significant differences in feeding rate between dominant hatchery and dominant wild salmon, or between subordinate hatchery and subordinate wild salmon.Hatchery salmon displayed lower feeding rates than wild salmon when they were held in separate compartments of an aquarium and compared at three temperatures. This difference in feeding rate probably was not a reflection of differences in adaptation to temperature or food preference, but, rather, was the result of interference with feeding caused by the more intense social interaction among hatchery fish.It is suggested that high levels of aggressiveness may contribute to mortalities of hatchery-reared salmon planted in streams because of loss of feeding time, excessive use of energy, and increased exposure to predators.

An unusually small, mature whitefish which appeared to be identical to the lake whitefish, Coregonus clupeaformis, was found in 22 lakes in northwestern Maine in 1957‐62. In most lakes the “dwarfed” form was found sympatric with “normal” lake whitefish, but populations that are completely dwarfed were found in three lakes. Distinct differences have been found in the size and age at which the two forms of whitefish become sexually mature, in their rate of growth, in their morphology, and in their erythrocyte antigens. Information on spawning habits provides further evidence of two separate breeding populations. All evidence leads to the conclusion that the two forms of lake whitefish are discrete, and that at least a partial barrier to gene flow exists between them. The differences between the two forms are highly variable from lake to lake, making any conclusions as to their systematic relationship tenuous. It is suggested that this variation may be due in part to varying degrees of convergence of two whitefish forms that once diverged from a common progenitor.

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We studied angler opinions regarding management options to apportion open-water and ice fishing effort in Maine. We found resident anglers favored policies seeking an even distribution of opportunity and harvest between open-water and ice fishing. Nonresidents, over 90% of whom fish only open water in Maine, clearly preferred management options favoring open-water fishing. These results suggest that fisheries managers may want to enhance open-water fishing opportunities, at the expense of ice fishing, on bodies of water that attract the largest number of nonresident anglers in order to bring tourism dollars into the state. Such actions, however, should not be undertaken at the expense of resident anglers, who make up the largest proportion of the angling public and who are the anglers with the greatest opportunities to influence management policies.