Publications

Experimental sea lamprey control by the Bureau of Commercial Fisheries on Lake Superior streams provided many new distributional records of the fish fauna. Seventy-one species were recorded from 175 streams. Specimens were collected at the electromechanical barriers, with electric shockers, with fyke nets, and during chemical treatment of streams. Maps showing stream records of each...

Samples were collected at 40 stations in western Lake Erie in 1961 to determine the species composition, distribution, and abundance of macrobenthonic organisms and to document changes since 1930, when a similar survey was made. The fauna in 1961 was composed principally of Oligochaeta, Tendipedidae (7 genera), Sphaeriidac (15 species), and Gastropoda (at least 8 species). Stations with...

No abstract available.

Colorimetric methods are described for the detection of residues of the selective lampricide, 3-trifluoromethyl-4-nitrophenol (TFM), in natural waters and fish tissues. Solvent extraction and anion exchange were used to separate and concentrate the lampricide, and to reduce high background colors which often interfere with the determinations. Data from the Pentwater and Muskegon Rivers...

Humper lake trout are one of the several races or subpopulations of lake trout in Lake Superior. This study is based on 3,705 fish collected on a reef south of Isle Royale near the eastern end. The mean lengths of humper trout from commercial gill nets were smaller than those of lean lake trout. Members of age-groups VII, VIII, and IX represented 81.5 per cent of the commercial humper...

Samples of flesh were excised from the middorsal region of 67 siscowets (Salvelinus namaycush siscowet) and 46 lake trout (Salvelinus n. namaycush) collected from Lake Superior. Chemical analysis of the samples revealed a range in fat content (dry weight) of 32.5 to 88.8 per cent in siscowets and 6.6 to 52.3 per cent in lake trout. Percentage fat increased progressively with increase in...

Lakes Huron, Michigan, and Superior are classified as oligotrophic lakes on the basis of their biological, chemical, and physical characteristics. Lake Ontario, although rich in nutrients, is morphometrically oligotrophic or mesotrophic because of its large area of deep water. Lake Erie, the most productive of the lakes and the shallowest, is eutrophic. Several changes commonly...

The northern pike is one of Ohio's largest game fish but is well known to comparatively few anglers. Large numbers of the big fish spawn in the Ohio marshes adjacent to Lake Erie. Movements related to spawning reach a peak in late March or early April. Later the spawning population disperses and is seldom represented in catches by experimental gear or by anglers. The short period of...

The successful stocking of the hatchery-reared lake trout (Salvelinus namaycush) in Lake Superior has imporved the outlook for rehabilitating stocks reduced to an extremely low level by predation from the sea lamprey (Petromyzon marinus). Marking the fish by fin-clipping to determine growth and survival benefits from holding young-of-the-year lake trout in the hatchery overwinter was...

No abstract available.

This report presents without interpretation methods used in and the results of chemical analyses, and supplemental observations of temperatures at depth, transparency, and meteorological conditions for Lake Michigan in 1954, 1955, 1960, and 1961.

No abstract available.