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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

A multi-scale approach to reconstructing landscape history in the Great Swamp National Wildlife Refuge, Morris County, New Jersey

Momsen, Jennifer L. January 2007 (has links)
Thesis (Ph. D.)--Rutgers University, 2007. / "Graduate Program in Ecology and Evolution." Includes bibliographical references (p. 137-157).
12

Can Patterns of Energetic Condition Explain Differences in the Productivity of Arctic and Common Terns at Petit Manan Island, Maine?

Agius, Stephen M. January 2008 (has links) (PDF)
No description available.
13

Assessing the Impacts to Society Associated with the Use of Alternative Ammunition for Hunting on National Wildlife Refuges

Cahill, Christopher 02 April 2021 (has links)
Attempts to eliminate lead ammunition use for hunting through regulatory approaches can be controversial and contentious, despite extensive scientific evidence of the detrimental effect of lead on wildlife species. In the United States, voluntary approaches to non-lead use that have used outreach and education in place of regulatory approaches have achieved sustained behavioral change in hunter ammunition choice. However, voluntary approaches to alternative ammunition use can be confronted with both practical and social barriers. In collaboration with U.S. Fish and Wildlife Service and U.S. Geological Survey Cooperative Research Units Program, this study assessed the practical and social barriers associated with a voluntary approach to transitioning to non-lead ammunition for hunting white-tailed deer (Odocoileus virginianus) on targeted National Wildlife Refuges in the Northeast United States. This thesis is presented in two sections. Section one examines the continued use of lead ammunition in the context of the North American Model of Wildlife Conservation (the Model). The Model presents a unique approach to wildlife conservation grounded in the sustainable use of wildlife resources maintained in a public trust. In accordance with the Model, wildlife resources in the trust are managed by the government at a population level to maintain trust resources in perpetuity for the benefit of current and future generations of the American public. Continued lead ammunition use for hunting that facilitates pathways to exposure for non-target species presents a unique challenge to a core principle of the Model – known as legitimate purpose -- and questions whether lead ammunition use can align with the Model even in the absence of population level impacts. In addition, chapter one explores whether continued lead ammunition use can be considered ethical hunting behavior under the current definition of a “clean kill”. Chapter two presents the results of a both a quantitative mail-back survey and qualitative focus group discussions conducted at three refuges in the Northeast Region: Rachel Carson in Maine, Edwin B. Forsythe in New Jersey and Rappahannock River Valley in Virginia. The mail-back survey assessed how current lead users view the practical barriers associated with the voluntary use of non-lead ammunition for the purpose of harvesting white-tailed deer and what factors would influence hunters to switch. Focus group discussions assessed hunter understanding of the mechanism of exposure for non-target species and how hunters contextualize the continued use of lead ammunition for the purpose of harvesting white-tailed deer.
14

Speciation in the genus sceloporus Sceloporus (Sauria, Iguanidae) as determined by cranial osteology and other characters

Larsen, Kenneth Rex 31 May 1973 (has links)
Numerical statistical methods were used to analyse the species in the genus Sceloporus using cranial osteology, external meristic and numeric characters, karyology, display behavior and geographic distribution. A new phylogeny for the genus is proposed with three main branches or Groups: Group I, a primitive group, evolved from Uta, Urosaurus and Sator in Miocene times. This Group speciated from gadoviae in the south to merriami in the north and contains 7 species in 3 species groups. Group II arose from Group I and evolved from centrally located pictus in all directions throughout Mexico. It contains approximately 19 species in 5 species groups. Group III also arose from the primitive stock of Group I and speciated from several desert refugia created by Pleistocene glaciation. Evolution of this Group in Mexico was generally from north to south with malachiticus extending as far south as Panama. This Group contains approximately 32 species in 5 species groups. It is suggested that the three main divisions of Sceloporus should be given taxonomic recognition.
15

REPORT OF AN INTERNSHIP WITH THE U.S. FISH AND WILDLIFE SERVICE AT THE PEA ISLAND NATIONAL WILDLIFE REFUGE, HATTERAS ISLAND, NORTH CAROLINA

Fegel, Sara Marie 17 February 2004 (has links)
No description available.
16

An Internship at the Kanuti National Wildlife Refuge with the U.S. Fish and Wildlife Service

Julianus, Erin L. 17 December 2010 (has links)
No description available.
17

Attentiveness and Time Budget of a Pair of Nesting Wood Storks

Clark, E. Scott 01 July 1980 (has links) (PDF)
An instantaneous sampling system was used to quantify nest attentiveness and time budget of a pair of Wood Storks (Mycteria americana) nesting at the Moore Creek colony on Merritt Island National Wildlife Refuge in 1977. The amount of time devoted to various activities during each stage of the 4-month reproductive cycle was examined and differences between stages evaluated. During the incubation period an adult was constantly at the nest site and the birds shared equally in the incubation duties. During the first four weeks of the 8-week pre-flight nestling stage, an adult was with the chicks continuously, although the adults discontinued brooding after the first week. In the latter four weeks of the pre-flight stage and 4-week post-flight stage, the amount of time spent in the colony by the adults diminished until the parents only returned to the colony for several minutes per day to feed the young. The time devoted to incubation, brooding, nest maintenance, and sexual displays declined during the breeding season, while the time spent "loafing" and away from the colony increased. Next defense, chick maintenance, and standing at the nest were maximal during the first half of the pre-flight stage.
18

Cerulean warbler breeding biology / Title from signature page: Cerulean warbler breeding biology in Big Oaks National Wildlife Refuge, Madison, Indiana

Roth, Kirk L. January 2004 (has links)
The Cerulean Warbler (Dendroica cerulea) is a Neotropical migrant bird species which is experiencing severe population declines. This study fills in gaps in the information available concerning Cerulean Warbler territoriality and breeding in a site in southeastern Indiana. During the summers of 2002 and 2003, 51 territories were mapped, with an average territory size of 0.21 hectares. Differences existed between territories and random sites for canopy cover, slope, canopy height, number of trees, diameter at breast height (DBH), the number of trees between 3 - 7.9 cm DBH, the number of trees between 8 - 14.9 cm DBH, the number of trees between 15 - 22.9 cm DBH, and the number of trees > 38 cm DBH. Nest productivity was very low in the study area, suggesting that Big Oaks National Wildlife Refuge was a sink population of Cerulean Warblers during the two years of the study. / Department of Biology
19

Is All Open Space Created Equal? A Hedonic Application within a Data-Rich GIS Environment

Neumann, Bradley C. January 2005 (has links) (PDF)
No description available.
20

Small mammal and bird abundance in relation to post-fire habitat succession in mountain big sagebrush (Artemisia tridentata ssp. vaseyana) communities

Holmes, Aaron L. 28 December 2010 (has links)
Fire is an important disturbance mechanism in big sagebrush (Artemisia tridentata) communities, yet little is known about wildlife population dynamics during post-fire habitat succession. I estimated the abundance of small mammals and birds in relation to fire history in mountain big sagebrush (A.t. spp. vaseyana) communities on the Sheldon National Wildlife Refuge in the northwestern Great Basin, USA. I employed a chronosequence approach that took advantage of multiple wildfires that had occurred in similar plant communities between 7 to 20 years prior to sampling. Belding’s ground squirrel (Spermophilus beldingii) were approximately 10 times as abundant in burned areas relative to adjacent unburned habitat regardless of the number of years since a burn occurred. Deer mouse (Peromyscus maniculatus) was more abundant on more recently burned sites, but not at sites closer to full vegetation recovery. Great basin pocket mouse (Perognathus parvus), sagebrush vole (Lemmiscus curtatus), and least chipmunk (Tamius minimus) abundance did not vary as a function of fire history, but some variance was explained by habitat features such as rocky areas and the canopy characteristics of sagebrush. Bird diversity was higher in unburned habitats irrespective of the number of years of recovery out to 20 years. Nine of the 12 most widely occurring species of birds in the study have population densities influenced by fire or post-fire habitat succession to at least 13 to 20 years following a burn. Sage Sparrow (Amphispiza belli), Black-throated Sparrow (Amphispiza bilineata), and Spotted Towhee (Pipilo maculatus) occurred at relatively low densities and were nearly restricted to unburned habitats. Green-tailed Towhee (Pipilo Chlorurus), Gray Flycatcher (Empidonax wrightii), American Robin (Turdus migratorius), and Brown-headed Cowbird (Molothus ater) occurred at lower densities in burned areas than adjacent unburned areas although the relationship was not strong for the latter two species. The magnitude of the difference in density between burned and unburned sites within a landscape diminished with the number of years of vegetation recovery for Green-tailed Towhee. Brewer’s Sparrow (Spizella brewerii) occurred at lower densities relative to adjacent habitat in the most recent burn, but occurred at higher densities after 20 years of habitat succession, suggesting a positive response with a multiple decade lag period. Horned Lark (Eremophila alpestris) and Vesper Sparrow (Pooecetes gramineus) respond positively to fire, but densities were similar to unburned areas after 20 years of habitat succession. An ordination analysis captured 86% of the variation in 12 bird species with 3 orthogonal axes. My research demonstrates that strong community structure exists for birds associated with mountain big sagebrush habitats, and that fire influences community structure for multiple decades. / Graduation date: 2011 / Access restricted to the OSU Community at author's request from Dec. 22, 2010 - Dec. 22, 2011.

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