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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.
61

Radikálny islamisti: trójsky kôň terrorizmus alebo kriminálnici / Radical Islamists: A Trojan Horse of Terrorism or Criminals

Gergely, Frederik January 2019 (has links)
This work focuses on analysis of radical Islamist (jihadist) terrorism in Europe with specific focus on refugees. The basic aim of this work is to determine, whether refugees are more prone to radicalization, criminal activity or terrorism. Special attention will be given to refugees that came to Europe since 2015 and the special aim is to determine, whether they can be considered as trojan horse of terrorism, criminals or they pose no threat in topic of either terrorism or criminality. This work is divided into three main chapters and numerous subchapters. In the first part of the work, the phenomenon of terrorism is closely analysed. This chapter concentrates on difficulties of achieving a common definition of terrorism, provides various definitions and their critique, looks on definitional elements and roots of terrorism, discusses theories of terrorism and presents various types of terrorism. Second chapter lists out the occurrence of jihadist terrorism in Europe since 2015 and reviews it. A special view is offered by listing out successful jihadist attacks committed by refugees since 2015. Third chapter focuses on the analysis of three things - radicalization among refugees, criminal activity among refugees and the possibility of the occurrence of migratory terrorism. The main research...
62

PPARγ Agonist and Antagonist Regulation of Migratory Adiposity in the Gray Catbird (Dumetella Carolinensis)

Valachovic, Abigail Corrine 21 April 2022 (has links)
No description available.
63

Migration Ecology of Vermivora Warblers

Kramer, Gunnar Robert January 2021 (has links)
No description available.
64

The Influence of Predator Exclosures and Livestock Grazing on Duck Production at Bear River Migratory Bird Refuge, Utah

West, Benjamin C. 01 May 2002 (has links)
Nest predation is a major factor impacting duck production and recruitment on breeding areas in North America. I surveyed waterfowl managers employed by the U.S. Fish and Wildlife Service and U.S. state wildlife agencies to determine their beliefs about nest predation and its management. Over 64% of respondents believed that rates of nest success on their management units averaged <30% between 1996-2000. Managers believed habitat management and direct predator control were the most effective techniques to reduce nest predation. The construction of predator exclosures around nesting habitat also has been recommended to reduce nest predation. Between 1999-2001, I evaluated the effectiveness of 4 predator exclosures to enhance duck nest success at Bear River Migratory Bird Refuge, Utah. During this period, rates of nest success in the exclosures were slightly higher than that within control plots, but still <15%. Although published guidelines commonly recommended predator fences ≤ 117 cm in height, I observed red foxes jump the 114-cm-high fences. Additional research is needed to identify effective predator fence designs. Wildlife managers have argued that periodic disturbance of vegetation should be a component of management on waterfowl breeding areas. Although many techniques are available to manipulate vegetation, grazing by domestic livestock has been controversial. Some researchers have reported that livestock grazing is detrimental to nesting ducks whereas others have argued that it can be beneficial. I evaluated the impact of a short-duration, high-intensity winter livestock grazing program on duck nesting at Bear River Migratory Bird Refuge. Following a winter grazing treatment, I measured visual obstruction on both grazed and ungrazed plots during the spring nesting season. Although visual obstruction readings on grazed plots were lower than those on rested sites early in the nesting season, those differences diminished as the season progressed. Winter grazing may impact early-nesting ducks like mallards (Anas platyrhynchos), but not late-nesting species like cinnamon teal (Anas cyanoptera) and gadwall (Anas strepera). In designing grazing programs to manage nesting cover, managers should consider their waterfowl production goals, the composition of breeding duck populations, type of grazing system, and climatic conditions.
65

Development of an Interpretive Document for the Bear River Migratory Bird Refuge

Burbridge, William R. 01 May 1972 (has links)
Since its inception, the National Wildlife Refuge System has been administered for management and restoration of habitat essential to the propagation and welfare of resident and wintering wildlife species. Acquisition of additional System units has been primarily directed to the benefit of the migratory bird resource. As of July 1, 1968 about 250 of the 321 refuge units were managed for the waterfowl resource (U. S. Department of Interior, 1968a). However, this growth of the System has been accompanied by an increase in recreational use of the refuges. In 1962, Public Law 87-714, the Refuge Recreation Act, was passed to provide direction for recreational development. The Act recognized that recreation must be limited in type and scope to avoid conflict with the primary wildlife management objectives. Although the primary function of the Refuge System is to meet the needs of wildlife, the entire System is based on the philosophical precept that the wildlife on these refuges is for the enjoyment of the public. It thus follows that refuges should provide for some public use. In recent analyses of America's resource picture, the fastest rising curves and projection are those of travel and the recreational use of wildlands (Clawson, 1963). Attendance records at our wildlife Refuges have grown at a rate of 12 percent annually. Except for boating and fishing at reservoir sites, the fastest growth in outdoor recreation since World War II has been in the use of National Wildlife Refuges (Clement, 1964).
66

Evaluating Migratory Stopover Success: Monitoring the Decline of Bird Populations at Hueston Woods Biological Station

Ecklar, Brooke Irene 31 July 2020 (has links)
No description available.
67

Waterbird and Seed Abundances in Migratory Bird Habitat Initiative and Non-Managed Wetlands in Mississippi and Louisiana

Weegman, Matthew Moraco 14 December 2013 (has links)
The USDA Natural Resources Conservation Service (NRCS) implemented the Migratory Bird Habitat Initiative (MBHI) in summer 2010 to provide wetlands for waterbirds inland from the Deepwater Horizon Oil Spill. To evaluate MBHI and associated wetland management practices, I estimated seed and waterbird densities in MBHI and non-managed wetlands in the Mississippi Alluvial Valley (MAV) of Mississippi and Louisiana. Although not statistically different, wetlands enrolled in MBHI contained 1.26 and 1.53 times more seed biomass and seeds consumed by waterfowl than non-managed wetlands, respectively. I also detected 3 times more dabbling ducks and all ducks combined on MBHI wetlands. When I combined density data for all waterbird species, MBHI wetlands contained more than 2 times as many birds than control wetlands. Management via MBHI increased waterbird and potential food abundances, suggesting NRCS consider sustaining MBHI and provide financial incentives to landowners for management of wetlands in the MAV and United States.
68

Fall Migrant Waterbird Community Structure and Stable Isotope Ecology in the Mississippi Alluvial Valley and Northern Gulf of Mexico: Use of Migratory Bird Habitat Initiative Sites and Other Wetlands

Foth, Justyn Richard 09 December 2016 (has links)
The Mississippi Alluvial Valley (MAV) was dominated by extensive lowland forests, but during the 20th century most of the MAV was converted to agricultural, aquaculture, and other human uses. These land-use changes created stopover migration and wintering habitats for waterfowl, shorebirds and other waterbird species. Before landscape modification of the MAV, shorebirds likely migrated past the MAV to wetlands along the northern Gulf of Mexico (NGoM). In 2010, the Deepwater Horizon oil spill impacted coastal marshes of the NGoM. The USDA Natural Resources Conservation Service implemented the Migratory Bird Habitat Initiative (MBHI) to provide waterbirds with wetlands inland of oil-impacted areas. My objectives were to 1) statistically model the waterbird community on wetlands in the MAV and NGoM, 2) estimate relative abundance of shorebird and other waterbirds in idled aquaculture ponds enrolled in MBHI and associated wetlands in the MAV and NGoM, and 3) collect shorebird feathers and blood for stable isotope analysis (13C/12C, 15N/14N) to assess foraging niches and potential migratory connectivity between MAV and NGoM habitats during 2012 – 2013. Consequently, autumns of these years were under a drought, extensively wet from Hurricane Isaac, and exhibited average precipitation in the post-hurricane recovery period which may have had an effect on waterbird assemblages differing by year, month, twice-monthly survey period, latitude, region, state, site, and water depth index. Latitude shifted north and water depth was narrowest when abundant wet habitat existed on the landscape in 2012. Bird abundances were greatest in 2011 and never recovered to these levels in 2012 or 2013, which may have reflected effects of drought concentrating birds on remaining wetlands in 2011 and subsequent to the hurricane. Stable isotope analysis of blood indicated spatial segregation of shorebird species. Neither blood nor feather carbon and nitrogen values revealed definitive linkage of sites between the MAV and NGoM. Shallow water habitat inland may be a limiting resource during migration for waterbirds, especially in drought years when other wetlands may have been limited. Thus, provision of wetlands (mudflat – 15 cm) by MBHI and other conservation strategies across the landscape may allow waterbirds access to needed resources during migration.
69

Migratory connectivity and carry-over effects in Northwest Atlantic loggerhead turtles (Caretta caretta, L.)

Ceriani, Simona 01 January 2014 (has links)
Migration is a widespread and complex phenomenon in nature that has fascinated humans for centuries. Connectivity among populations influences their demographics, genetic structure and response to environmental change. Here, I used the loggerhead turtle (Caretta caretta, L.) as a study organism to address questions related to migratory connectivity and carry-over effects using satellite telemetry, stable isotope analysis and GIS interpolation methods. Telemetry identified foraging areas previously overlooked for loggerheads nesting in Florida. Next, I validated and evaluated the efficacy of intrinsic markers as a complementary and low cost tool to assign loggerhead foraging regions in the Northwest Atlantic Ocean (NWA), using both a spatially implicit and spatially explicit (isoscapes) approach. I then focused on the nesting beaches and developed a common currency for isotopic studies based on unhatched eggs, which provide a non-invasive and non-destructive method for more extensive sampling to elucidate isotopic patterns across broader spatiotemporal scales. Lastly, I found that intra-population variations in foraging strategies affect annual and long-term reproductive output of loggerheads nesting in Florida. Understanding geospatial linkages is critical to the fostering of appropriate management and conservation strategies for migratory species. My multi-faceted approach contributes to the growing body of literature exploring migratory connectivity and carry-over effects.
70

Species Composition, Relative Abundance, and Habitat Occurrence of Neotropical Migratory Birds Overwintering in Dominica, West Indies

Roades, Heather Nicole 09 August 2012 (has links)
No description available.

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