2,549 research outputs found
Breeding bird populations of Irish peatlands : capsule peatlands are very important habitats for birds despite low species diversity
Get PDFAims to describe the variation in breeding bird populations that occur on different types of Irish peatlands and their associated habitat characteristics.
Methods: Bird abundance and diversity were compared between four peatland habitat types: fens; raised bogs; Atlantic blanket bogs; and montane blanket bogs at twelve study sites using transects. Various measures of habitat quality were also taken at each location.
Results: Only 21 species were recorded during the study with Meadow Pipit Anthus pratensis and Sky Lark Alauda arvensis accounting for over 80% of all birds recorded. Fens had greater bird species diversity and densities than the other three peatland types. Raised bogs, Atlantic blanket bogs and montane blanket bogs were very similar in terms of their avian diversity. Each of the recorded bird species were associated with different aspects of the peatland habitat.
Conclusion: This study shows that despite the relatively low avian species diversity of Irish peatlands, they are of enormous conservation value due to the presence of species of high conservation concern such as Red Grouse (Willow Ptarmigan) Lagopus lagopus and Eurasian Curlew Numenius arquata.Other funderEnvironmental Protection Agency (EPA)ke, ab, sp, li - TS 26.04.1
The density and diversity of birds on farmland in West Africa
No full textThe area of land farmed in Africa is predicted to double by the year 2050 yet very few African studies have investigated the impact of different farming intensities and regimes on bird communities. This study examined avian species richness and diversity along with the densities of some common bird species on the Jos Plateau, Nigeria, in relation to habitat features on farmland over a gradient of differing farming intensities. The study area exhibited a variety of different levels of farming which differed in the habitat available for birds. Birds normally associated with savanna woodland were more associated with less intensive farming, and open-country birds were more associated with more intensive sites, with more species of birds observed where farming was less intensive. Common species of birds using cultivated land associated with different crops, with acha and millet being the most commonly used. Tree density was the most important variable predicting avian species richness and diversity, with medium tree density predicting the highest species richness and diversity. The densities of two common farmland birds were predicted best by tree density, but varied in their responses to the habitat variables, with common bulbul, a savanna generalist, associating more with less intensive, wooded areas and red-cheeked cordon-bleu, an open savanna granivore, associating with medium intensity, more open farmland. Whinchats were common in open, intensively farmed areas with few trees and good herbaceous vegetation cover. The data presented indicates the importance of retaining natural features of savanna habitat in farmland in order to maintain high avian diversity on farmland. More detailed studies are needed in order to determine the mechanisms involved in the associations observed and collaborations between ecologists and social scientists will be necessary to develop effective policies to limit the impact of the intensification of agriculture in Africa on avian biodiversity
Ecology, impacts and management of pest birds
Get PDFPests can impact significantly upon the economy, the environment and on human and animal health. However, for pest birds there are surprisingly few studies of these impacts and how to reduce them. The aim of this thesis is to advance our understanding of the ecology, impacts, and management of pest birds using case studies for each of the three main impacts.
In considering economic impacts I estimate pest bird abundance, describe a novel method for measuring bird damage, and evaluate the efficacy of lethal and non-lethal methods in vineyards and orchards. Using data across 185 property years, netting was found to be the most effective in reducing bird damage. Shooting was not as effective but was one-third of the cost and had 13% lower damage compared with nil-treatments. Scaring with electronic devices and visual deterrents had no effect on bird damage. Despite their widespread use, lethal methods had limited effectiveness for reducing pest abundance.
In considering environmental impacts introduced mallards on Lord Howe Island were used as a case study. Phenotypic characteristics suggest that mallards have supplanted the native Pacific black duck on Lord Howe Island. Management alternatives are evaluated and discussed.
In considering health-related impacts wild birds and avian influenza in Australia was used as a case study. Here, the ecology of Australia’s Anseriformes, and the epidemiology, modes of transmission, and the factors influencing the prevalence of avian influenza in Australia’s wild birds are investigated. Risk profiles to improve the efficiency and relevance of wild-bird surveillance are also provided.
The case studies presented demonstrate that an understanding of a pest’s ecology, efficient measures of impacts, and thorough evaluations of surveillance and management strategies are essential for effectively managing their economic, environmental and health-related impacts
Bald Eagle Nest Surveys at Fort A.P. Hill 2017
No full textThe bald eagle (Haliaeetus leucocephalus) was taken off of the federal endangered species list in August of 2007 but continues to receive federal protection through the Bald and Golden Eagle Protection Act (BGEPA) and the Migratory Bird Treaty Act. Department of Defense (DOD) guidance directs military installations to protect nesting locations by following the National Bald Eagle Management Guidelines published by the US Fish & Wildlife Service in order to maintain compliance with the Migratory Bird Treaty Act and the Bald & Golden Eagle Protection Act. Due to its size, land use history, and geographic location, Fort A.P. Hill harbors a large and increasing population of nesting bald eagles (Haliaeetus leucocephalus). In the past two years, three new nesting locations have been discovered incidentally, and it is believed that many more exist and have yet to be located. A systematic inventory of nesting locations is critical to maintaining these protections without any adverse effects to the military training mission
Wittgenstein Didn’t Agree with Gödel - A.P. Bird - Cantor’s Paradise
No full textIn 1956, a few writings of Wittgenstein that he didn't publish in his lifetime were revealed to the public. These writings were gathered in the book Remarks on the Foundations of Mathematics (1956). There, we can see that Wittgenstein had some discontentment with the way philosophers, logicians, and mathematicians were thinking about paradoxes, and he even registered a few polemic reasons to not accept Gödel’s incompleteness theorems
Wittgenstein Didn’t Agree with Gödel - A.P. Bird - Cantor’s Paradise
No full textIn 1956, a few writings of Wittgenstein that he didn't publish in his lifetime were revealed to the public. These writings were gathered in the book Remarks on the Foundations of Mathematics (1956). There, we can see that Wittgenstein had some discontentment with the way philosophers, logicians, and mathematicians were thinking about paradoxes, and he even registered a few polemic reasons to not accept Gödel’s incompleteness theorems
STRUCTURE OF THE ART-SPACE IN THE STORY "I" BY A.P. POTEMKIN
Get PDFThe author performs the analysis of the art space structure in A.P. Potemkin's story "I". Several interrelated spatial models are allocated and described: household space, natural space, social space, psychological space, transpersonal space
Pressure drop and turbulence statistics in transpired pipe flow
No full textMeasurements of turbulent flow in a horizontal pipe subjected to wall transpiration are presented. Results include data on global flow rates and pressure drop, and local mean and fluctuating velocity profiles. Two distinct flow transpiration rates are studied, = / = 0.0005 and 0.001. The effects of flow transpiration on the friction-coefficient are compared with theoretical predictions. The theory furnishes predictions accurate to 3\%
Fully Turbulent Mean Velocity Profile for Purely Viscous non-Newtonian Fluids
No full textThe characteristic near wall behavior of turbulent flow of purely-viscous non-Newtonian fluids is discussed for both power-law (P.-L.) and Herschel-Bulkley (H.-B.) rheological models. A proper scaling is presented for H.-B. fluids to establish an analogy with power-law fluids with same flow index. To provide reference data for turbulent flow of non-Newtonian fluids, DNS simulations of power-law fluids are conducted in a rectangular channel for a large range of power-law indices ( = 0.5, 0.69, 0.75, 0.9, 1, 1.2). The DNS data show that the mean velocity profile in the viscous and logarithmic layers follow expressions of the form and respectively, where shows a logarithmic dependency on the flow index.Comparison with some experimental data shows the above formulation to be valid for Reynolds numbers (based on shear velocity) as high as 1000
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