Premium
Life History of the Utah Sculpin, Cottus Bairdi Semiscaber (Cope), in Logan River, Utah
Author(s) -
Zarbock William M.
Publication year - 1952
Publication title -
transactions of the american fisheries society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.696
H-Index - 86
eISSN - 1548-8659
pISSN - 0002-8487
DOI - 10.1577/1548-8659(1951)81[249:lhotus]2.0.co;2
Subject(s) - sculpin , cottus , fishery , predation , biology , trout , fish <actinopterygii> , rainbow trout , zoology , ecology
The study of the Utah sculpin in Logan River was based on 801 specimens collected from 1949 to March 1951. Fish were collected by use of an electric shocking machine generating 600 watts and 220 volts. Numbers of fish taken were as high as 150 per 0.1 mile of stream. Preferred habitats were areas of coarse gravel and small rocks. Age determination was made from vertebrae and length‐frequency distributions indicated that the age determinations were accurate. Determinations of sex were by external observation and were difficult except during the breeding season. Relationship between standard length (millimeters) and weight (grams) is described by the following formula:W = 4.236 × 10 −4 L 2.900 The coefficient of condition (K) increased with length of fish up to 60 millimeters of standard length and then decreased in fish of larger size. The greatest variation in K occurred in fish less than 50 millimeters long. The food consisted almost entirely of aquatic insects, principally Diptera. Ephemeroptera, Plecoptera, and Trichoptera were consumed in almost equal numbers. Food availability and preference were determined from bottom samples of the river. Competition with trout for food is minimized by the fact that the sculpin is a bottom feeder and rainbow and brown trout are primarily surface feeders. Predation of trout eggs by the sculpin was very slight.