Thesis (Ph.D. Earth Sciences)--University of Waikato, 2005. / Includes bibliographical references (p. 232-246) Also available via the World Wide Web.

Thesis (Ph.D.)--Baylor University, 2009. / Includes bibliographical references (p. 104-117).

There are today many areas and types of water storage. The uses to which these are put are many, and the prospect for the future can only be that there will be an increase in the number of these reservoirs. These areas are usually operated with regard only for power production, irrigation, or storage, but there is a growing concern about the effects on wildlife which this type of operation may have. Fluctuating water levels, and falling water levels are not restricted to man-made impoundments tut are characteristic of many of then. Biologists have observed that these variations in water levels are often harmful to some forms of wildlife. Fluctuating water levels generally were found to cause damage to waterfowl nests. The amount of damage, the amount of water rise and the time involved are values which have generally remained unknown, largely perhaps because some other aspects was of greater importance in the nesting studies. There is a descending scale of values which have been placed on natural resources, and it is generally agreed that the waterfowl concerned would rank below the value derived from the impounded waters. Where it is practical, the management of these impoundments should take wildlife into consideration. To have intentions of good management is not sufficient to effect conservation; these intentions must be implemented with the proper tools. This study was designed to discover magnitudes of cause and effect, and perhaps it will point the way to a more efficient utilization of associated resources. It was possible that the results of this study would show that there was little damage to waterfowl. On the other hand, if significant damage were to be discovered, contributing causes could be more closely delimited and so point the way toward corrective measures.

No description available.

Muskellunge (Esox masquinongy) and Northern Pike (E. lucius) are ecologically and economically important fish species that rely on coastal habitats in Georgian Bay, especially coastal marshes. These habitats have adapted to the high natural water-level fluctuations of Lake Huron but are threatened by changing water-level conditions associated with global climate change. The overall goals of this thesis were to identify important esocid habitats and understand how their suitability will be affected by changing water levels. First, I used tracking information from radio telemetry studies of esocid populations in spatially distinct regions of Georgian Bay to identify important habitats during breeding and non-breeding seasons. I documented the strong affinity of Muskellunge to re-use specific spawning grounds close to known nursery habitat in coastal marshes. Both Muskellunge and Northern Pike used coastal marshes during the non-breeding season, and physical habitat structure was a more important driver of habitat use in the summer months than water temperature. Next, I created a GIS model using only hydrogeomorphic features (depth, slope, and wave exposure) to map the extent of coastal marshes throughout eastern and northern Georgian Bay to assess how habitat would shift under a range of possible lake elevations scenarios (175.5 – 177.5 m). The geomorphology at low lake levels favoured large areas of shallow (< 0.5 m) habitat at the expense of deeper habitats (0.5 – 1.5 m) that can support an aquatic vegetation community more suitable for young esocids. I used a similar approach to develop a Resilience Index to rank coastal marshes according to their resilience/vulnerability to stable low water levels, for use as a regional screening tool to identify critical esocid habitat. This research advances the understanding of the effects of water levels on coastal marshes and provides applicable tools to assist in conservation and management of these important recreational fisheries. / Thesis / Doctor of Philosophy (PhD) / This Ph.D. thesis describes how changes in water levels may affect habitats used by Muskellunge and Northern Pike, two important species of sport fish, in Georgian Bay (Lake Huron). Coastal wetlands were identified as critical habitats, especially for early-life stages, and are directly influenced by water levels of the Great Lakes. I developed several tools to assist in identification, evaluation, and management of coastal wetlands in Georgian Bay, a relatively undisturbed coastal region in Ontario. These tools use physical features of the landscape to predict how wetlands will respond to different lake-level conditions and influence habitat suitability for Muskellunge and Northern Pike, as well as Great Lakes fish communities in general. My thesis provides tools for environmental agencies to adaptively manage important fish habitat in a period of unpredictable water levels associated with global climate change.

Thesis (M.S.)--University of Tennessee, Knoxville, 2008. / Title from title page screen (viewed on Sept. 14, 2009). Thesis advisor: Matthew J. Gray. Vita. Includes bibliographical references.

Thesis (M.S.)--University of Tennessee, Knoxville, 2009. / Title from title page screen (viewed on Oct. 28, 2009). Thesis advisor: Matthew J. Gray. Vita. Includes bibliographical references.

<p> The Ontario shoreline of Lake Huron is one of the most populated areas, with reference to recreational purposes, in Ontario. However, with the rising water levels of the Great Lakes during 1972 and again in 1973, serious problems of beach erosion have resulted, particularly in the area of Grand Bend and Port Franks. This loss of sand has threatened cottages built on the dunes in addition to destroying breakwalls, steps, and boat launching ramps along the beach. It was with the idea of learning more about the beach, and possibly suggesting some methods of beach protection, that the research for this thesis was initiated. During the course of study, the author also became interested in the Ausable River and the associated flooding and erosion problems, with reference to past, present, and future attempts to solve or at least alleviate these difficulties. Thus, one section of the thesis is concerned with the Ausable River alone. </p> <p> The beach studied is actually the culmination of a series of raised beaches, formed during higher post-glacial lake stages. These raised beaches formed a bar separating the now non-existent Ausable Bay from Lake Huron, forming a lagoon eastward of the beach. This bar extends from Grand Bend, in a southwest direction, and culminates at Kettle Point. However, for the purposes of this thesis, that section between Grand Bend and Port Franks received the greatest amount of concentrated study. Over the years, the lagoon, formed by the growth of the bar has silted up, and is now drained for agricultural purposes. </p> <p> The modern beach was observed during the summer of 1972. This involved, profiling of a portion of the shore and offshore topography, procuring beach samples for later analysis, the use of sequential air photographs for observing changes over time, and the analysis of wind and wave data, along with many conversations with local residents and personal observations. </p> <p> The subsequent study of the above factors revealed several major conclusions regarding the beach. First, that it has good natural protection against erosion due to the abundance of sand s tored by the dunes. Second, the beach appears to be in an equilibrium state, however as lake levels fluctuate, so must the beach level, thus destroying the equilibrium for a period of time. With the lowering of the water level, the beach will become wider, exposing sand to the onshore winds, which will in turn rebuild the dunes with the blowing sand. Finally, because of the prximity of man-made structures to the beach, on the unstable dunes, some method of stabilizing the beach is necessary. That suggested is a groin system, designed and constructed by the local authorities. This would help prevent erosion and would eliminate the often vain and possibly dangerous, (to the natural environment), attempts by individuals to halt erosion. </p> <p> This is by no means a complete study of the area and its problems. Further consideration should be given to proposals which have been presented to the local conservation authority, and which were designed to alleviate some of these problems, particularly at Port Franks. The suggestions made here should also be given further thought. In addition to these practical problems, the actual growth of the original bar would provide an interesting subject for study. </p> / Thesis / Bachelor of Arts (BA)

Typescript. / Digitized by Kansas State University Libraries

The growing demand for water in the arid regions of the West increases the need for optimal allocation of water among competing uses. An efficient allocation of water between instream and out-of-stream uses has been impeded by institutional constraints and the scarcity of information regarding instream flow benefits. The objectives of this thesis were to provide preliminary economic data on the value of instream water in "producing" recreational fishing and to examine the effect of forestry, agriculture, and livestock practices on temporal streamflow patterns and anadromous fish production. The steelhead trout (Salmo gairdneri) sport fishery within the John Day River basin in north-central Oregon provided the setting for this research. The interdisciplinary methodology employed in estimating the marginal value of water with respect to steelhead production consisted of two tasks. The first task involved valuing a marginal change in the quality of the steelhead recreational fishery. The contingent valuation method (CVM) was selected for this purpose. Both open- and closed-ended willingness-to-pay (WTP) questions were included in a questionnaire administered to John Day River steelhead anglers during the 1986/87 steelhead fishing season. Survey data were analyzed to arrive at individual and aggregate bid functions relating WTP to expected angling success rates. Results indicate that, under current conditions, the average angler is willing to pay approximately $7.20 to catch an additional steelhead. The second task of the instream water valuation methodology was directed at deriving a streamflow/steelhead production relationship. By including variables influencing steelhead production in a Ricker stock-recruitment model, it was possible to develop a model which could be estimated using linear regression techniques. Some difficulty arose, however, with interpretation of the model due to the unavailability of cohort escapement data and the subsequent use of standing crop data. While possibly masking the true magnitude of streamflow's effect on fish production, this drawback was not deemed limiting within the general context of the interdisciplinary methodology. Results of the biological model conformed to a priori expectations. Increases in summer and winter streamflows led to increased steelhead survival, whereas higher spring flows increased mortality levels. Other results indicate that the John Day Dam was responsible for a 31.5 percent decline in the population index for the 1969-1983 period. Combining the economic and biological results into one equation yielded an estimate of the marginal value of summer instream water in "producing" recreational steelhead angling. Similar equations were developed for winter and spring flows. The marginal value of water in producing recreational steelhead fishing within the John Day basin was estimated at $0.56 per acre-foot for summer flows, $0.046 for winter flows, and -$0.075 for spring flows. By including out-of-basin benefits, these values increased to $2.26, $0.19, and -$0.30, respectively. In comparison, water's value in irrigation within the John Day basin has been estimated at between $10 to $24 per acre-foot. However, nonuse values of steelhead, as well as the increased production of other fish species (such as spring chinook salmon) were not included in the instream water values. In addition, no attempt was made at valuing instream water's contribution to boating, camping, or other benefit-producing activities. A secondary objective of this thesis was to briefly examine the possible benefits accruing to other instream and out-of-stream users due to an alteration in streamflow patterns. In addition, the impact of activities by other resource users -- namely forestry, agriculture, and livestock production --on anadromous fish production was reviewed. Improper management practices by these activities can negatively impact the aquatic and riparian ecosystems. While no firm conclusions were drawn, it appears the quality of these ecosystems, as opposed to the amount of streamflow, has the largest marginal impact on anadromous fish populations. / Graduation date: 1988