During 1980 and 1981 respectively, 2425 and 4028 yellow perch 150-359 mm were Floy-tagged from June through August at four sites in Indiana waters of Lake Michigan. Most of the 6453 perch were tagged from mid-June to early August and almost 90% were less than 210 mm.An overall recapture rate of 3.2% (204 fish) was obtained by April 1, 1982. Site recapture rates were positively related to the numbers of fish tagged. Slightly over 92% of all fish were tagged at sites M and K and 94.5% of all recaptures originated from these two sites. Second season recaptures accounted for 25.5% of all recaptures. Peak recapture rates occurred in July. Sources of recaptures were 67.6% from sport fishermen, 25.5% from commercial fishermen, and 6.9% from Indiana Department of Natural Resources, Ball State University trawl catches and other sources.Most recaptured perch were in the 150-229 mm length interval, but an apparent size selection by both commercial and sport gear existed towards 180-229 mm perch. The recapture of large numbers of 150-159 mm fish indicated survival of small perch was not an important factor influencing size selection. Information on sizes of fish recaptured by sex and age was insufficient for evaluation.Although straight line movements of up to 166 km occurred, most fish remained near the original tagging sites. Distances traveled were similar for fish from all tagging sites in 1980, 1981 and for second season recaptures. Over 76% of all fish were recaptured in Indiana waters and about 86% traveled less than 32.0 km from the original tagging sites. The majority (64%) of fish leaving Indiana waters were captured nearby at New Buffalo and Union Pier, Michigan. About 68% of all recaptures were received within 60 days of release. Even though considerable variability was evident in the distances traveled with time, no seasonal trends were observed for perch of various sizes.Simple regression analysis of data for combined years revealed only 27% of all variation in distance traveled by perch was accounted for by the time at large (days) prior to recapture. Multiple regression analysis revealed the time at large was more important than fish length in relation to distance traveled, accounting for 27.3% and 0.2% of the explained variability, respectively. Data including second season recaptures more accurately represented these relationships and indicated these variables were poorly related to distance traveled. Examination of residuals showed a dramatic and statistically undesirable increase in unexplained variability was associated with far ranging fish. Other factors should be considered in future multiple regression analyses.Indiana yellow perch stocks appear to be fairly discrete entities. The majority of fish tended to remain periods of at least one year.

The lake sturgeon, Acipenser fulvescens, was once abundant throughout Canada and the United States, however, high commercial harvests and habitat alterations have dramatically reduced most populations. The species was extirpated from many rivers that it once inhabited, and has been designated as threatened or endangered throughout its range. Currently, few healthy lake sturgeon populations remain and the species is receiving considerable attention with respect to its protection and recovery. Although considerable effort is underway to conserve the species, several factors, including over-harvest and habitat alteration, pollution and a general lack of understanding about lake sturgeon ecology and behavior continue to hamper recovery efforts. This thesis examined the ecology and behavior of juvenile lake sturgeon within a 41 km long impounded section of the Winnipeg River, a large river in the Canadian Shield, over a three-year period (2006 – 2008). Habitat preferences, species associations, diet, and movement were described on a seasonal basis. Biological characteristics were also described for juvenile lake sturgeon within the study area. Studies presented in this thesis are among the first conducted for juveniles of this species in the Hudson Bay drainage basin, and from large riverine environments in general. Results are important, not only for improving our understanding of lake sturgeon at the juvenile life history stage, but for facilitating further research. In particular, future research studies identified in the final chapter have the potential to enhance our understanding of factors influencing mortality during the early life history stages of the lake sturgeon, and therefore, greatly enhance recovery efforts.

Lake size is a strong control on lake function and on how lakes interact with the environment. For example, lake size is related to carbon burial rates in lake sediments. Lake size distribution (the number of small, medium, and large lakes per unit area) can be used to extrapolate lake function to landscapes at local, regional and global scales. This research examined the utility of using radar satellite imagery (ALOS PALSAR) and existing spatial data (CanVec) for the construction of a new Canadian lake database, which was then used to estimate carbon accumulation in Canadian boreal lake sediments. The capability of ALOS PALSAR images for classifying lakes from eight pilot regions across Canada was assessed by direct comparison to existing CanVec data. The PALSAR lake classification differed between -1.8% to 18.0% for overall lake area and -56.0% to 196.0% for overall lake count compared to CanVec. The wide range in difference can be explained by limitations in resolution, classification method, and how a lake was defined. While the temporal resolution of PALSAR was superior, it did not provide better spatial resolution and accuracy than existing datasets. PALSAR’s utility therefore is in short term change determination. Consequently, CanVec was used to construct the final database describing lake distribution in Canada, resulting in over 13.2 million features with a total area of almost 1.2 million km2. Lake database results suggest that the scaling rules used in previous studies to estimate the number of very small lakes regionally and globally have limits. The use of real lake data allowed for a better understanding of regional differences in lake distribution across Canada that was not possible with scaling rule approaches. Estimates of carbon accumulation in boreal Canada lake sediments based on the new CanVec lake distribution and literature-based accumulation rates ranged from 1.65 and 2.34 Mt C yr-1, or roughly equal to the carbon emissions of 300,000-450,000 cars per year. Similarly, it would require only 36 years for Canada’s total annual emissions to account for all the carbon accumulation in Canadian boreal lakes over the Holocene (last 10,000 years). Thematic products derived from the lake database suggest that number of lakes is more important than the distribution of small, medium and large lakes when estimating carbon accumulation in the lake sediments of boreal Canada. / Graduate

The East Kirkton Limestone outcrops in the Bathgate Hills area of central Scotland. The deposit is Visean (Lower Carboniferous) in age and is the site of a tropical freshwater lake set within a richly vegetated volcanic terrain. The succession consists of an unusual sequence of laminated, spherulitic and massive limestone beds, interbedded with thin mudstones, siltstones and abundant volcaniclastic horizons. This study investigates the palaeoenvironment of the East Kirkton lake, and for the first time presents convincing evidence for the presence of hot springs at East Kirkton. Two distinct mounds of massive limestone are located at the north end of the East Kirkton quarry and are interpreted as hot spring vent deposits. Calcite samples from the Lower Mound have light δ¹⁸O_PDB values consistent with precipitation at elevated temperatures ranging from 45°C to ˜80°C, whereas samples from the laminated lake sediments have heavier δ¹⁸O_PDB values, consistent with precipitation at lower temperatures. The East Kirkton Limestone is unique because it contains a variety of unusual radial fibrous calcite (RFC) precipitates, including mm-sized spherules, oncoids, and laminated botryoidal accretions. These are found within the laminated limestone and also within the Lower Mound of massive limestone, and many of them contained filamentous and cellular microbial remains and are within the definition of microbial carbonates. This study provides good evidence for a microbial involvement in the formation of the East Kirkton laminated accretions. A study of modern stromatolites from Lake Tasek Dayang Bunting, Malaysia highlights close similarities with the East Kirkton accretions in terms of morphology and microstructure. Both have a nodular growth morphology and laminated interior consisting of layers of radial fibrous carbonate botryoids interspersed with organic-rich micritic laminae. The modern stromatolites are covered by a microbial community comprising filamentous bacteria and cyanophytes, plus diatoms and associated mucilage, and microbes are thought to have played an essential role in the morphogenesis of both the modern and ancient examples.

Thesis (Ph. D.)--Oregon State University, 1969. / Typescript. Includes bibliographical references (leaves 146-149). Also available on the World Wide Web.

Thesis (M.S.) in Ecology and Environmental Science--University of Maine, 2006. / Includes vita. Includes bibliographical references (leaves 67-71).

Thesis (M.S.)--Eastern Illinois University, 2008. / Includes bibliographical references (leaves 50-52).

Thesis(M.S.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references.

Thesis (M.S.)--University of Chicago, 1972. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 179-182).

Thesis (M.S.)--University of Chicago, 1972. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 179-182).