Publications

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...

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 history of stocking of lake trout (Salvelinus namaycush) in the Great Lakes is reviewed. The study of movements is based on capture of 24,275 fin-clipped lake trout taken in experimental gill nets and trawls and commercial gill nets. Yearling lake trout planted from shore dispersed to 15-fath (27-m) depths in 3A? hr. Most fish remained within 2 miles (3.2 km) of the planting site 2...

The sex, length, and weight were determined of nearly all recently transformed sea lampreys migrating downstream in the Carp Lake River, Michigan, in the fall, winter, and spring of 1960-61. Similar data were collected from samples of an earlier run in the Carp Lake River and of runs in three other tributaries of Lakes Huron and Michigan. The sex ratio of the 1960-61 migrants in the Carp...

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...

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...

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...

No abstract available.

The species and size composition and the abundance of the cisco (Leucichthys spp.) population of Lake Michigan have undergone drastic changes since the sea lamprey became established in the 1940's. The changes were measured by the catches of gill nets of identical specifications fished at the same seasons, depths, and locations in 1930-32, 1954-55, and 1960-61. The two largest ciscoes...

The round whitefish, though rarely abundant, is widely distributed in northern waters. It is one of the least studied of the coregonines; the present report is but the second for Great Lakes waters. Commercial production in Lake Michigan has been tightly confined to the northern portion. The period 1924-30 showed the best production: 200,000 to 359,000 pounds. Since 1956, production has...

The need to obtain adequate water samples immediately above a lake bottom or at a precisely defined depth is not new. The problem is of particular concern in a large section of central Lake Erie, where dissolved oxygen concentration may be reduced to 1 ppm or less in the hypolimnion and where the metalimnion frequently extends to or within 30 or 60 cm of the bottom (Becton 1963; Cam 1962...

No abstract available.