Results from Experimental Plantings of Legal-Sized Brook Trout (Salvelinus Fontinalis) and Rainbow Trout (Salmo Irideus)
- 1 January 1939
- journal article
- Published by Oxford University Press (OUP) in Transactions of the American Fisheries Society
- Vol. 68 (1) , 196-210
- https://doi.org/10.1577/1548-8659(1938)68[196:rfepol]2.0.co;2
Abstract
An intensive creel census in conjunction with monthly releases, during the fishing season, of legal‐sized trout, approximately one‐half of which were jaw‐tagged or fin‐clipped, furnished data for the evaluation of such plantings in the Pine River, Michigan. Nearly 8,500 hours of fishing yielded 3,171 brook trout and 3,333 rainbow trout for an average catch of 0.77 fish per hour. Forty‐six per cent of the brook trout reported and 21 per cent of the rainbows were from these plantings. Incomplete records of the marked fish showed recovery of 19.8 per cent of 7,513 brook trout and 17.5 per cent of 4,007 rainbows planted. The catch per hour by weekly periods ranged from 0.32 to 1.35. The average catch per hour for the Pine was considerably higher than for the other streams that were covered by a similar census but not planted with large fish. The plantings influenced the catch for a period of from two to three weeks. Apparently few of these fish survive to the next season. Movement of planted fish was mainly upstream regardless of the method of planting. Within two weeks the fish which remained were uniformly distributed over the stream. “Spot” planting resulted in a larger percentage caught than did scattering by boat, but increased “meat fishing.” Every planting during the open season caused a decided rise in the catch of wild fish of the same species. It is concluded that although planting legal fish during the season temporarily and artificially increases the catch, it may deplete a stream of wild adults. This depletion will affect natural production and may result in poorer fishing in succeeding years. A program for planting legal‐sized trout appears justified only in heavily fished waters incapable of supporting a permanent trout population during the summer or where no results from natural reproduction are possible, or where an overpopulation of stunted trout exists.Keywords
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