Thesis (M.S.)--Humboldt State University, 2009. / Includes bibliographical references (leaves 70-75). Also available via Humboldt Digital Scholar.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1991. / Vita. Abstract. Includes bibliographical references (leaves 73-82). Also available via the Internet.

Generalist predators are typically considered to eat foods in proportion to their availability. I show that striped skunks, archtypal generalists, do not just eat foods as available, do not even just select for foods, but switch selection among prey types. In various experiments I showed that skunks do not change prey preference, but they do change preference for where they look for prey, they learn what types of microhabitats prey are found in, they form olfactory search images of prey (OSI), they form these OSI both in the short term and in the long term, both for many small prey items and for few large ones, they form OSI's in relation to what habitat the skunks are searching in, and they change foraging pattern in response to finding different types of foods. Many other predators use one or other of these mechanisms, but rarely has an animal been shown to use several--I argue that this is because biologists have not looked for many such mechanisms together, and that it is common for generalist predators to switch among prey types. If it is common, then generalist predators should exert density-dependent predation on prey, and should to some extent, regulate prey densities. I discuss various field studies of predator-prey relationships that suggest this. / Graduate

Thesis (Ph. D.)--University of Hawaii at Manoa, 1995. / Includes bibliographical references (leaves 132-140). / Microfiche. / xii, 140 leaves, bound ill. 29 cm

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 98-104). Also available via the Internet.

Thesis (Ph. D.)--Ohio state University, 1922. / Cover title. Autobiography. Published in full as Bulletin of the Ohio Agricultural experiment station no. 388, Nov. 1925 (1 p. l., p. 239-364). Bibliography: [3] p. at end.

Thesis (M.Sc.)--College of William and Mary. / Vita. Includes bibliographical references.

Hybrid striped bass (Sunshine Bass) were raised in an indoor recirculating aquaculture system incorporating concrete culture tanks, sump tanks, rotating biological contactors and liquid oxygen injection and underground U-tubes for aeration. Fish were anesthetized by two methods after harvest to reduce metabolic activity. Hybrid striped bass were either held in cooled water or water with elevated CO₂ levels prior to sacrificing and filleting. Control fish were filleted immediately or three hours after harvest. The objectives of this study were to determine the effects of these treatments on fillet quality and to develop indicators of quality and shelf life. All fillets were stored at 1-4°C and tested over a 14-day period. Analyses included aerobic plate count, pH determination, texture measurements (Instron), color measurements (L* a* b* scale) and sensory panel evaluations of cooked portions for appearance, taste, odor and texture. Fillets of the cooled water treatment group had the highest pH and were significantly less firm (Instron). Log phase growth and the time for spoilage levels of microorganisms to grow were delayed one day in the CO₂ fillets. In addition, the CO₂ treated fillets were generally rated higher in sensory attributes than the other fillets, especially late in the test period. / Master of Science

The comparative performance of striped bass Morone saxatilis (STB) and hybrid striped bass M. saxatilis x M. chrysops (HSB) was evaluated in Claytor Lake, Virginia. This study assessed: 1) habitat use versus habitat availability for STB and HSB; 2) seasonal movement patterns, movement rates, and emigration rates of STB and HSB; and 3) angler catch rates of STB and HSB in Claytor Lake. In general, STB and HSB used similar habitats throughout this study. However, HSB used warmer (2-3'aC) water than STB during spring of 2001 and 2002. During the summer months, fish selected the coolest water temperature available that contained adequate (> 2.0 mg/L) dissolved oxygen. Striped bass habitat was more degraded than HSB habitat during summer stratification of both years. Both moronids exhibited similar seasonal movement patterns. Upstream spawning migrations took place in March at 9-10'aC. Summer habitat was restricted to the lower 1/3 of Claytor Lake, whereas fish used the entire reservoir during other seasons. Minimum daily movement rates were similar between species and seasons (0.2-0.5 km/h). Hourly movement rates were also similar between species (0.2-0.3 km/h). One tagged fish from the reservoir was recovered below the dam, suggesting low rates of emigration. Poor tag return rates by anglers limited confidence in estimation of exploitation rates. However, based on estimated natural and handling mortality rates and tag-reporting rates, estimated annual fishing mortality was 26% for STB and 14% for HSB, lower than rates found in Virginia′s Lake Gaston and Smith Mountain Lake. / Master of Science

Since the introduction of hybrid striped bass M. chrysops x M. saxatilis to Claytor Lake, Virginia in 1993, relative abundance of striped bass Morone saxatilis has dropped disproportionately to stocking density. Potentially deleterious interactions between the two fishes that may limit recruitment to age 1 were considered in terms of trophic relationships, physiological indices of health, overwinter survival, and post-stocking predation. Both fishes preferred habitat types characterized by structure-free sand or gravel substrates, but striped bass and hybrid striped bass did not exhibit significant diet overlap during the growing season. At a total length of approximately 120 mm, the juvenile moronids shifted from a mixed diet of zooplankton and invertebrates to a diet comprised primarily of age-0 fishes. However, after becoming piscivorous striped bass preyed primarily upon age-0 alewife Alosa pseudoharengus, while hybrid striped bass consumed age-0 sunfishes. Striped bass achieved mean total lengths of 229 and 173 mm by the end of the growing season in 2001 and 2002, respectively. Stocked into the reservoir three months later than striped bass, mean hybrid striped bass total lengths reached 133 mm at the end of the 2002 growing season. Condition factor, relative weight, and lipid index values were low, but nearly equivalent for both striped bass and hybrid striped bass throughout this study. Overwinter starvation of smaller (< 150 mm total length) striped bass was observed for the 2001-2002 sampling season. Predation upon stocked fingerlings was not considered significant in limiting juvenile survival; only three fingerling moronids were found in the examination of stomach contents of 200 potential predators captured near stocking sites. It does not appear that resource competition with hybrid striped bass during the growing season resulted in increased overwinter mortality of juvenile striped bass. Delayed stocking of hybrid striped bass lessens the potential for trophic competition between striped bass and hybrid striped bass at this early life-stage. / Master of Science