Thesis--University of Wisconsin--Madison. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 215-226).

Food habits of the alewife, Alosa pseudoharenous, were studied in Indiana waters of Lake Michigan at 10 m (32.8 ft.) stations o transects at Burns Ditch and Michigan City from June to October, 1970. Organisms in stomachs were expressed as percent of the total volume, percent frequency of occurrence, and percent composition.Food selectivity of the alewife was studies at the 10 m station on Michigan City transect. Plankton samples were taken concurrently with fish samples and percent composition of various food items in plankton and stomach samples were compared to elucidate selection with an electivity index.The occurrence of copepods and cladocerans in alewife stomachs from Burns Ditch and Michigan City transects was similar; however, Michigan City alewife stomachs had three more cladoceran species than Burns Ditch samples. Oligochaetes were not present in any Michigan City stomach samples, and Pontoporeia affinis was not found in any Burns Ditch samples. When comparing these two sample sites, the alewife food habit differences may be due to difference in substrate, water quality, and the influence of the Burns Ditch river mouth.Based upon frequency of occurrence and percent volume, zooplankton comprised the largest portions of food in adult alewife (140 mm [5.5 in.] and greater) alewife stomach samples taken from June to October in 10 m of water on Michigan City transect. Cladoceran occurrence and percent volume in alewife stomachs increased monthly from June to September and October. Cyclops bicuspidatus, the major food item contributing to copepod percent volume in alewife stomachs, generally declined from July to October.Alewife size, for fish ranging from 140-169 mm (5.5-6.6 inc.) and 170-189 m (6.7-7.4 in.) did not appear to influence percent volume and frequency of occurrence of major food items consumed. Food selectivity of the two size groups was also similar for planktonic food species examined.Alewives ranging from 140-189 mm selected positively for the female Cyclops bicuspidatus while copepodites were always negatively selected. During October, large cladocerans, Leptodora and Daphnia, were positively selected. Although Diaptomus spp. Were similar in size to the female Cyclops, it was always negatively selected. The alewife selection for Bosmina longirostris was strongly negative in June, July, and October, but ws near random in August and September. Since the B. longirostris density in August and September was relatively high, the near random E values may indicate random filter feeding by the alewife. Prey size, mobility, and density appear to be major influences on adult alewife food selection.

Thesis--Wisconsin. / Includes bibliographical references.

Thesis--University of Wisconsin--Madison. / Typescript. Vita. Computer program on microfiche in pocket (leaf 214). Description based on print version record. Includes bibliographical references (leaves 215-225).

Thesis (M.S.) in Marine Biology--University of Maine, 2004. / Includes vita. Includes bibliographical references (leaves 70-79).

Thesis (M.S.) in Marine Biology--University of Maine, 2009. / Includes vita. Includes bibliographical references (leaves 44-48).

No description available.

Alewives in Claytor Lake matured at age I at 160 mm TL. Fecundity of gravid females increased with age and length, ranging from 17,307 eggs at age I to 37,147 eggs at age III. The majority of alewife spawning was concentrated in littoral areas of a large embayment. Spawning period was protracted (13 weeks), beginning in May and lasting until August. Females apparently did not extrude eggs at one time, but spawned repeatedly. Growth rates of young-of-the-year alewives were higher in 1978 than in 1979, possibly due to reduced intraspecific competition for food and space following an alewife die-off in winter 1977-1978. Rapid growth of young-of-the-year alewives allowed the earliest spawned cohorts to become morphologically unavailable as prey to age 0 and age I sportfish by mid-July. However, the extended alewife spawning season mitigated availability of alewives by assuring, through subsequently spawned cohorts, that they remain available as prey through the growing season. Cyclopoid copepods were the principal food item in diets of alewives 6 to 35 mm TL. Bosmina longirostris dominated diets of alewives 36 to 70 mm TL. Size-selective planktivority of larval alewives was equivalent to that of adults at sizes as small as 31 mm TL, and may have significantly contributed to observed changes of zooplankton communities toward smaller forms. Concentrations of young-of-the-year alewives in littoral areas may exert a negative impact on age 0 sportfish which depend on littoral zooplankton populations as a food source. / M.S.

Incorporating molecular genetic data into management decisions would provide fisheries managers with new tools to identify the magnitude of population structure, metapopulation dynamics, at risk populations, and possible genetic interactions between species, so that management strategies could be tailored to better support long-term viability of species and populations. Alewife (Alosa pseudoharengus) and Blueback Herring (Alosa aestivalis) are two closely related anadromous clupeid fishes native to the Atlantic coast of North America. Current management strategies for these two species, collectively known as river herring, take no account of stock structure or even the distinction between the two species. Using 12 neutral microsatellite loci, I examined at multiple spatial scales the patterns of population structure and genetic differentiation for river herring, with particular reference to comparisons of population structure in the U.S., where extensive stocking has occurred, and Canada, where there has been no stocking. Results suggested strong population structure within the Canadian portion of the range and weaker population structure in the U.S. portion. Highly significant genetic isolation by distance (IBD) for parts of the range unaffected by stocking provided evidence of natal homing and limited dispersal. The differing IBD results obtained in three Canadian regions may reflect differences in historical biogeographical factors and contemporary dispersal patterns among regions. Very weak differentiation and an absence of significant IBD for American stocked populations provided evidence that stocking has reduced genetic differentiation between populations in the U.S. portion of the range, except for two divergent stocked populations that appeared to have resisted homogenization. Evidence of recent population bottlenecks were identified in both U.S. and Canadian populations. The genetic structure of Blueback Herring populations appeared to be similar to that seen in Alewife. When sampled in the same river, Alewife and Blueback Herring were strongly differentiated, although hybrids of the two species were detected. Evidence of genetic impacts of stocking, regional variation in patterns of population structure and complex genetic interactions between the species suggest that current management strategies should be re-evaluated.

Thesis (M.A.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / The incorporation of C14 label into the lipids of the spermatozoa of man and fish (the alewife, Alosa pseudoharengus,) was studied. Washed spermatozoa of man and the alewife were incubated in vitro under aerobic conditions with glucose-C14 (r.1.). The sperm cells were extracted with chloroform-methanol, and the crude lipid extracts were purified to remove radioactive contaminants. The lipid extracts were fractionated into the major classes of lipids by column chromatography and further separated by thin-layer chromatography. Glycerides, phosphatides and cholesterol were isolated and identified and their radioactivity was determined. C14 label was found exclusively in the lycerol portion of the glycerolipids of the spermatozoa of both man and the alewife. The rates of incorporation of glucose-C14 into the total lipids were 54.4 ummoles/1010 human spermatozoa/hour and 1.8 ummoles/10^10 alewife spermatozoa/hour. In the sperm lipids of both species the glycerides were the most actively labeled components with the diglycerides having the highest specific activities and the triglycerides being the most abundant components. Whereas in human spermatozoa the glyceride content was 20% of the total lipids, in the alewife spermatozoa the fraction constituted only 4% Cholesterol, 14 - 15% of the total sperm lipids in both species, was not labeled. The polyglycerophosphatide fraction was the most abundant and the most actively C14-labeled component in the phosphatides of alewife spermatozoa. Most of the radioactivity incorporated in the phosphatides of human spermatozoa was found in the lecithin and cephalin fractions. Lecithin was the phosphatide of highest specific activity. By means of infrared spectroscopy, evidence of the presence of plasmalogen was found in the phosphatides of human, but not of alewife spermatozoa. Unlike mammalian spermatozoa, fish spermatozoa have poor glycolytic capacity. Nevertheless, the present work shows that fish spermatozoa can utilize glucose for the synthesis of glyceride glycerol at adequate rates. The demonstration of the biosynthesis of lipids from glucose by the spermatozoa of man and fish suggests that sperm may utilize carbohydrate not only for the maintenance of motility through the energy generated by glycolysis, but also for the replenishment of lipid reserves. / 2999-01-01