1000 resultados para Fish--Michigan


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Each no. has also a distinctive title.

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Bird damage to commercial fruits has long been a problem in many coun- tries, but the true magnitude of the damage incurred is difficult to determine objectively. Often the opinions of fruit growers provide the only measure of importance. In 1972, the U.S. Fish and Wildlife Service, the Michigan Department of Agriculture, and the Statistical Reporting Service of the U.S. Department of Agriculture obtained quantitative information on bird damage to tart cherries (Prunus mahalob) in Michigan. The results of the survey are presented in this paper.

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Heavy metal-rich copper mine tailings, called stamp sands, were dumped by mining companies directly into streams and along the Lake Superior shoreline, degrading Keweenaw Peninsula waterways. One of the largest disposal sites is near Gay, Michigan, where tailings have been moved along the shoreline by currents since mining ceased. As a result, the smallest sand particles have been washed into deeper water and are filling the interstitial spaces of Buffalo Reef, a critical lake trout spawning site. This research is the first to investigate if stamp sand is detrimental to survival and early development of eggs and larvae of lake sturgeon, lake trout, and Northern leopard frogs, and also examines if the presence of stamp sands influences substrate selection of earthworms. This study found that stamp sand had significantly larger mean particle sizes and irregular shapes compared to natural sand, and earthworms show a strong preference for natural substrate over any combination that included stamp sand. Additionally, copper analysis (Cu2+) of surface water over stamp sand and natural sand showed concentrations were significantly higher in stamp sand surface water (100 μg/L) compared to natural sand surface water (10 μg/L). Frog embryos had similar hatch success over both types of sand, but tadpoles reared over natural sand grew faster and had higher survival rates. Eggs of lake sturgeon showed similar hatch success and development over natural vs. stamp sand over 17 days, while lake trout eggs hatched earlier and developed faster when incubated over stamp sand, yet showed similar development over a 163 day period. Copper from stamp sand appears to impact amphibians more than fish species in this study. These results will help determine what impact stamp sand has on organisms found throughout the Keweenaw Peninsula which encounter the material at some point in their life history.

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This research project measured the effects of real-world content in a science classroom by determining change (deep knowledge of life science content, including ecosystems from MDE – Grade Level Content Expectations) in a subset of students (6th Grade Science) that may result from the addition of curriculum (real-world content of rearing trout in the classroom). Data showed large gains from the pre-test to post-test in students from both the experimental and control groups. The ecology unit with the implementation of real-world content [trout] was even more successful, and improved students’ deep knowledge of ecosystem content from Michigan’s Department of Education Grade Level Content Expectations. The gains by the experimental group on the constructed response section of the test, which included higher cognitive level items, were significant. Clinical interviews after the post-test confirmed increases in deep knowledge of ecosystem concepts in the experimental group, by revealing that a sample of experimental group students had a better grasp of important ecology concepts as compared to a sample of control group students.

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It has been well documented that many tribal populations and minority groups across the nation have been identified as being at high risk of the adverse health effects created by consuming fish that have been contaminated with mercury, PCBs, DDT, dioxins, and other chemicals. Although fish consumption advisories are intended to inform fish consumers of risks associated with specific species and water bodies, advisories have been the subject of both environmental injustices and treaty rights’ injustices. This means that understanding fish contaminants, through community perspectives is essential to good environmental policy. This study examined the fish contaminant knowledge, impacts on fishing and fish consumption, and the factors that contribute to harvesting decisions and behaviors in one tribal nation in the Upper Peninsula of Michigan, the Keweenaw Bay Indian Community. Using ethnographic methods, participant observation and semi-structured interviewing, fieldnotes were kept and all interviews were fully transcribed for data analysis. Among seventeen fishermen and women, contaminants are poorly understood, have had a limited impact on subsistence fishing but have had a substantial impact on commercial fishing activity. But ultimately, all decisions and behaviors are based on their own criteria and within a larger context of knowledge and understanding: the historical and cultural context. The historical context revealed that advisories are viewed as another attack on tribal fishing. The cultural context revealed that it is the fundamental guidance and essential framework associated with all harvesting beliefs, values, and traditional lifeways. These results have implications for advisories. ‘Fish’ and ‘contaminants’ appear differently based on the perceptions and priorities of those who encounter them.

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Strontium and neodymium radiogenic isotope ratios in early to middle Eocene fossil fish debris (ichthyoliths) from Lomonosov Ridge (Integrated Ocean Drilling Program Expedition 302) help constrain water mass compositions in the Eocene Arctic Ocean between 55 and 45 Ma. The inferred paleodepositional setting was a shallow, offshore marine to marginal marine environment with limited connections to surrounding ocean basins. The new data demonstrate that sources of Nd and Sr in fish debris were distinct from each other, consistent with a salinity-stratified water column above Lomonosov Ridge in the Eocene. The 87Sr/86Sr values of ichthyoliths (0.7079 - 0.7087) are more radiogenic than Eocene seawater, requiring brackish to fresh water conditions in the environment where fish metabolized Sr. The 87Sr/86Sr variations probably record changes in the overall balance of river Sr flux to the Eocene Arctic Ocean between 55 and 45 Ma and are used here to reconstruct surface water salinity values. The eNd values of ichthyoliths vary between -5.7 and -7.8, compatible with periodic (or intermittent) supply of Nd to Eocene Arctic intermediate water (AIW) from adjacent seas. Although the Norwegian-Greenland Sea and North Atlantic Ocean were the most likely sources of Eocene AIW Nd, input from the Tethys Sea (via the Turgay Strait in early Eocene time) and the North Pacific Ocean (via a proto-Bering Strait) also contributed.

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In October 1980 the U.S. Army Corps of Engineers conducted a beach nourishment project at the Lexington (Michigan) Harbor on the southwest shore of Lake Huron, a project designed to mitigate beach erosion attributable to the installation of the harbor. In response to a request from the Coastal Engineering Research Center (CERC), the U.S. Fish and Wildlife Service's Great Lakes Fishery Laboratory conducted a Corps-funded study from June 1980 to October 1981 along a 8.4-kilometer segment of shoreline adjacent to the harbor to determine the effect of the Corps' beach nourishment project on the nearshore aquatic environment. The study performed by the service included aerial photographic surveys of the study area; measurement of dissolved oxygen, turbidity, and suspended particulate matter levels; and collection of lake bottom sediments, macrozoobenthos and fish. Analysis of the aerial photographs showed that the beach face profile changed markedly during the study as a result of beach nourishment. Dredging of about 19,000 cubic meters of beach sediment from an accretion area adjacent to the harbor's north breakwater caused the beach face to recede, while deposition of this sediment on a feeder beach south of the harbor caused the beach face there to extend lakeward.

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Pottery, Islamic, Ilkhanid; 5 in.x 11 17/64 in.; stonepaste; molded and glazed

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Includes bibliographical references (page 3).

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Mode of access: Internet.