Premium
First‐Year Survival and Growth of Steelhead Stocked as Fry in Lewis Creek, Vermont
Author(s) -
Wentworth Roderick S.,
Labar George W.
Publication year - 1984
Publication title -
north american journal of fisheries management
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.587
H-Index - 72
eISSN - 1548-8675
pISSN - 0275-5947
DOI - 10.1577/1548-8659(1984)4<103:fsagos>2.0.co;2
Subject(s) - stocking , salmo , growing season , zoology , biomass (ecology) , fishery , biology , fish <actinopterygii> , ecology
The survival and growth of juvenile steelhead (Salmo gairdneri) stocked in Lewis Creek, Vermont were investigated in 1980 and 1981. Steelhead stocked in May 1980 as fry at rates of 84 per 100‐m 2 unit, and 176 per unit occurred in October at densities of 9‐18 and 19 per unit, respectively. The mean density 1 year after stocking was 4 per unit, or 4% of the number of fry originally stocked. The high losses between October and the following May might have resulted from unusual weather conditions and some downstream movement in the spring. At the lower stocking density, mortality was high during the first month following release, low during the rest of the growing season, and high over the winter. Numbers declined more slowly during the growing season in the section stocked at 176 per unit. However, the resulting density and biomass in October and the following May were similar to that observed within the area stocked at 84 per unit. By the end of the growing season, the average length, weight, and biomass of young‐of‐year fish was 99 mm, 8.5 g, and 151 g/unit, respectively. One year after stocking, these values were 117 mm, 15.4 g, and 64 g/unit, respectively. Survival observed in Lewis Creek in the first growing season during 1980 and in previous years for different stocking densities suggested that stocking more than 100 fry per unit is unnecessary.