Avian flight cannot fail to impress; from the huge migratory distances covered by albatrosses to the dexterity shown by a feeding hummingbird, the performance of birds in flight is remarkable. Until now research into free flight (i.e. not in a wind tunnel or other artificial environment) has been limited to observations from the ground. Here I use a collection of novel techniques, based on the use of onboard instrumentation carried by the bird, to explore if and how this performance might be underpinned by their flexible flight configuration. In the Introduction (chapter 1) to the thesis I investigate previous work into the stability and control of birds in flight. In chapter 2 I investigate a selection of manoeuvres seen commonly in flight, and describe the ways in which they exploit the flexible configuration of the eagle. Then (chapter 3), using an Inertial Measurement Unit (IMU) containing an integrated camera and Pilot-tube I measure the forces acting on the body of the bird in flight, the airspeed of the bird, and using custom-written software, I extract the configuration of the tail from the video. Using the measured configuration of the tail I estimate the lift generated by the tail according to a series of simple aerodynamic models. These are good predictors of the variation in the normal load factor acting on the bird. This suggests that the tail of the eagle is used primarily in soaring flight to balance the bird along the pitch axis. In chapter 4 I further investigate the configuration of the tail, I find that the spread and angle of attack of the tail covary, but that the twist of the tail is adjusted independently. In chapter 5 I explore one manoeuvre, the wing tuck, in more detail. With reference to a 'mean wing tuck' of the key variables I suggest that it is a response to a drop in wing loading, which suggests that it may be a response to atmospheric turbulence. I then investigate the frequency of wing tucking and our principal finding is that it is increased on days when the wind speed is greater, further suggesting that it is a response to atmospheric turbulence. Finally in the Discussion (chapter 6) I summarise the thesis. I also consider future avenues for research into the control and stability of avian flight and discuss some of the limitations of the methods used in this thesis.

The large size, extensive range, and irnporta.nt corrnnunity role of the Golden Eagle (Aguila chrysaetos L.) and the Bald Eagle (Haliae-etus leucocephalus L.) attract considerable scientific interest. Sorne aspects of their life history have been investigated and reported in detail, but their rapidly declining numbers (Sprunt and Ligas 1966, Cottam 1961) necessitate new investigations into all phases of their life history and particularly into population dynamics.

A research report submitted in partial fulfIlment of the degree of Master of Science in Quantitative Conservation Biology to the Faculty of Science, University of the Witwatersrand, Johannesburg, / No abstract

The Golden Eagle Aquila chrysaetos canadensis Linn. is facing extinction in much of its range. In the Western Hemisphere its numbers are restricted primarily to the mountainous regions west of the 99th meridian, from extreme northern Alaska to northern Mexico (Hobbie and Cade, 1962) and from timberline in Colorado to below sea level in Death Valley, California (Summer, 1929a).

A Dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science. April, 2013 / Recognising the mechanisms that led to the deposition of the Plio-Pleistocene caves of South Africa provide an irreplaceable window into the environment at the time. Differentiating between various accumulating agents based on the markings and accumulation variances has become an integral part of palaeontological research. Large birds of prey have been investigated for their connection to the Australopithecus africanus type specimen, commonly, the Taung Child. The verreaux’s eagle, Aquila verreauxii, was investigated in this study to establish whether it produced a taphonomic signature that would be distinguishable from other similarly sized raptors and small mammalian carnivores. Prey remains were collected from 11 nesting-sites in the Gauteng and Northwest Provinces as well as nesting-sites from across the Northern and Western Cape Provinces. The objective was to illustrate how prey selection was directly influenced by the immediate environmental stresses. Prey was analysed in terms of prey choice, skeletal part representation and the markings that the skeletal elements bore. Of the total of 886 specimens that were collected, rock hyrax (Procavia capensis), hares (Lepus sp.), Smith’s red rock rabbit (Pronolagus rupestris) and helmeted guineafowl (Numida meleagris) were the most common. The skeletal part representation directly mirrors the feeding behaviour of Verreaux’s eagles: body parts with larger muscle attachments and skeletal elements covering choice meat options were most often targeted and damaged. Finally, ten damage types were recorded as well as the combinations thereof, of which chewed and crenulated edges, V-nicks, removal of bone and punctures featured prominently. The results showed that verreaux’s eagles do leave a characteristic taphonomic signature in terms of the assemblage composition as well as the markings on bone surfaces.

The expansion of wind power comes with additional risks for bird populations, one of which is the collision with wind turbine components, mainly the rotating blades. In order to mitigate this risk, few systems on the market propose solutions with modules that deter the birds from the wind turbine or trigger the temporary shutdown of the turbines.The thesis seeks to obtain a common view from different stakeholders in order to create a list of requirements that the bird protection systems must have so as to be accepted by all the parties involved in the wind industry in Sweden. In order to meet this objective, interviews were conducted with interested stakeholders. Consequently, the interviews were summarized and common points were extracted to create a list of requirements and additional suggestions.Firstly, a comprehensive literature review was done that has pointed out issues like impacts of wind farms on bird species, especially raptors, causes of bird mortality, environmental legislation in European Union and Sweden, and current solutions on mitigating the risk of collisions with wind turbines onshore. Additionally, the author looked up into the most efficient ways to engage the stakeholders in constructive discussions and develop an easy framework for presenting the requirements.The primary data was collected through interviews with stakeholders representing 12 organizations. In the next steps, the data was analyzed by summarizing each interview and identifying the common and differentiating points in respondents’ views and suggestions over automated bird mitigation systems. The identified points laid the basis for a list of requirements considered important for safe and efficient bird mitigation systems in Sweden. Among others, stakeholders identified that the most crucial issues regarding bird mitigation systems are the response time to shutdown of the turbine, distance from the birds’ species living areas, need of species identification in bad weather conditions and night time and overall financial feasibility of such technologies.

Thesis (M. A. (Sociology)) -- University of the North, 2000 / Refer to the document / NRF (National Research Foundation)

In response to the recent delisting of the bald eagle as an endangered species, the Three Affiliated Tribes of the Fort Berthold Indian Reservation, the University of Arizona, and the National Park Service undertook this collaborative study to identify continuities and discontinuities in eagle knowledge and acquisition and use of eagle parts by members of the Mandan, Hidatsa, and Arikara Nation (MHA), and to document cultural resources associated with eagles in three North Dakota national parks. Interviews with tribal consultants who possess eagle rights were integrated with ethnographic, archaeological, and archival data. This research finds that although there have been major changes in how MHA people acquire eagles for personal and religious use since the early 20`" century, beliefs and practices associated with eagle demonstrate cultural continuity. There remains a strict adherence to protocols regarding the handling of eagles and the possession and transfer of eagle knowledge, and there is a persistent belief in the eagle's ability to animate people, objects, and places. The eagle feather remains an indicator of social status, spiritual power, and identity, and eagle parts continue to be crucial elements in the performance of major religious ceremonies. Several site types associated with eagles and eagle trapping were identified, and all three parks either contain eagle resources, or are associated with parts of the eagle landscape. While trapping pits and trapping lodges are no longer used for taking eagles, they retain significance as sources of supernatural power and spiritual knowledge. These sites are spiritually active, and are important places for conducting fasts, seeking visions, and making religious offerings. Tribal consultants believe that the power imbued in these sites is attributed to their past role in the establishment and perpetuation of relationships between their ancestors and the spiritual world during annual trapping expeditions. Both site types are culturally significant in their familial and clan associations, their reflection of traditional land uses unique to the Missouri River environs, and their role in the transformative religious experiences of ancestors. There is a desire within the tribal community to preserve eagle trapping pit sites and, even more so, trapping lodge sites. In order to maintain the sites' spiritual integrity, consultants prefer that they not be accessible to the general public.

No description available.

Theses (M.F.A.)--Rochester Institute of Technology, 1990. / Includes bibliographical references (leaf 23).