Thesis (Ph. D.)--Michigan State University. Dept. of Fisheries and Wildlife, 2006. / Title from PDF t.p. (viewed on Nov. 20, 2008) Includes bibliographical references. Also issued in print.

Thesis (M.S.)--University of Wisconsin--Madison, 1983. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

The present study is, in part, a description of meristic variation in the pygmy whitefish, Prosopium coulteri, of British Columbia fish with those of other areas. The species was shown to be highly variable meristically both within and between populations. There are indications in some characters of a north-south cline of meristic counts. One character (gill raker counts) seems to form a V-shaped curve of variation. The major part of the study is a comparison of the growth and relative growth of fish from four British Columbia lakes. The two "giant" forms from MacLure and McLeese Lakes are more like one another in relative growth than like either of the two dwarf forms inhabiting Cluculz Lake or Tacheeda Lake. The possible relationship between growth, form and environment is discussed. / Science, Faculty of / Zoology, Department of / Graduate

The distribution of Prosopium cylindraceum (Pallas) and Coregonus clupeaformis (Mitchill) in Algonquin Park, Ontario, suggested that there may be some interaction between these species. In large lakes where both species are present the C. clupeaformis population is always dominant; in small lakes only, one species is present. During the summer of 1963 the ecological relationships between these species were studied. Lakes Opeongo and Lavieille each contained both species, while in Lakes Redrock and Happy Isle only P. cylindraceum was present. Gill nets were set at frequent intervals, to determine the depth range occupied by the two species and to provide material for stomach analysis and age and growth data. Temperature and dissolved oxygen levels were recorded regularly using standard limnological techniques. The depth range occupied by both species was not strongly correlated with the thermal structure or oxygen level of the lake. P. cylindraceum in sympatric situations invariably occupied a shallower depth range than did C. clupeaformis. Where the latter species was absent P. cylindraceum were frequently found in a wide range of depths. P. cylindraceum from Lake Opeongo fed heavily on larval insects and to a lesser extent on bottom-dwelling crustacea. C. clupeaformis from the same lake fed mainly on bottom-dwelling crustacea plus some insects and molluscs. P. cylindraceum in Lakes Redrock and Happy Isle fed almost entirely on plankton crustacea. Zooplankton was of importance as a primary food source for whitefish. Age and growth data have shown that there is a direct correlation between the relative importance of plankton in the diet and the rate of growth of the fish. Fish from Lakes Redrock and Happy Isle had a much higher growth rate in both length and weight than the two species in Lake Opeongo. In the latter lake C. clupeaformis grew faster than P. cylindraceum. Large lakes with adequate zooplankton production will support both P. cylindraceum and C. clupeaformis, but the better adaptation of C. clupeaformis to plankton feeding may account for its greater success as indicated by its wide distribution, large numbers, and high rate of growth. / Science, Faculty of / Zoology, Department of / Graduate

Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 90-94).

Thesis (Ph. D.) -- Utah State University, Dept. of Fisheries and Wildlife, 1974. / Includes vita. Includes bibliographical references (leaves 161-171).

Thesis (Ph. D.)--University of Michigan, 1920. / "From Bulletin of the Bureau of fisheries, vol. XLIII, 1927, part II. Document no. 1048." Bibliography: p. 632-643.

Thesis (M.S.)--University of Wisconsin--Stevens Point, 2007. / Submitted in partial fulfillment of the requirements for the degree Master of Science in Natural Resources (Fisheries), College of Natural Resources. Includes bibliographical references (leaves 156-174).

Thesis (Ph. D.)--University of Michigan, 1920. / "From Bulletin of the Bureau of fisheries, vol. XLIII, 1927, part II. Document no. 1048." Bibliography: p. 632-643.

Limnological conditions in lakes of the Skeena drainage, British Columbia, have been examined to ascertain what factors may be restricting the distribution and/or abundance of the Eastern and Rooky Mountain whitefishes. The Eastern whitefish is known to be in only four Skeena lakes, and the Rocky Mountain whitefish in all Skeena lakes which have been investigated. It is probable that the Eastern whitefish has not entered other Skeena lakes because the lake conditions are not suitable for its establishment. Such conditions are mainly warm waters, shallow depths, and small area; and are sometimes the heavy silting of the water, and the resultant poor food supply. It is not numerous in any of the four lakes, probably because of the relative poor abundance of bottom food organisms, particularly in the absence of such organisms as the amphipod Pontoporeia. Conditions are apparently most favourable for Eastern whitefish in oligotrophia lakes. Rocky Mountain whitefish appear to favour eutrophic lakes, and are most abundant in lakes where a good supply of bottom food is assured by the absence of such potential competitors as the Peamouth chub and Squawfish. There is no evidence of any heavy predation on either of the two whitefish. It is improbable that any physical barrier has limited the distribution of these fish. / Science, Faculty of / Zoology, Department of / Graduate