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Breeding, dispersal, and migration of urban peregrine falcons in eastern North AmericaGahbauer, Marcel A. January 1900 (has links)
Thesis (Ph.D.). / Written for the Dept. of Natural Resource Sciences. Title from title page of PDF (viewed 2009/06/08). Includes bibliographical references.
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Parental care of peregrine falcons in interior Alaska and the effects of low-altitude jet overflightsPalmer, Angela G. 14 December 1998 (has links)
To assess the impact of low-altitude jet overflights on parental care, we examined
nest attendance, time-activity budgets, and provisioning rates of 21 Peregrine Falcon
(Falco peregrinus) pairs breeding along the Tanana River, Alaska in 1995 and 1996.
Several intrinsic and extrinsic factors influenced attributes of nesting behavior. Female
nest attendance declined substantially with progression of the nesting cycle, while male
attendance patterns were consistent throughout the nesting cycle. Further, although
females typically performed most of the incubating, male attendance at the nest area
varied considerably among breeding pairs. Both prey item delivery rates and estimated
prey mass delivery rates increased with brood size. Prey item delivery rates per nestling,
however, decreased with increasing brood size; yet estimated prey mass delivery rates per
nestling did not vary with brood size. Peregrine Falcons apparently maintained constant
provisioning rates per nestling as brood size increased by increasing average prey size.
We found evidence that nest attendance and time-activity budgets of Peregrine
Falcons differed during periods of overflights compared with reference nests, but differences depended on stage of the nesting cycle and gender. Males had lower nest ledge attendance during periods when overflights occurred than males from reference nests when data from the incubation and early nestling-rearing stages of the nesting cycle were combined. Females apparently compensated for lower male ledge attendance by attending the ledge more during overflown periods compared to females from reference nests, although this trend was not significant. During late nestling-rearing, however, females perched in the nest area less during periods when overflights occurred than females from reference nests. We did not see a relationship between nest attendance and the number of overflights, the cumulative number of exposures experienced by each nesting pair, or the average sound exposure level of overflights. Nor did we find evidence that nestling provisioning rates were affected by overflights. Low altitude jet overflights did not markedly affect nest attendance, time-activity budgets, or nestling provisioning rates of breeding Peregrine Falcons. / Graduation date: 1999
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Breeding biology and ecology of the peregrine falcon (Falco peregrinus) in West GreenlandBurnham, William A. 01 April 1975 (has links)
During the last twenty years marked declines in Peregrine Falcon populations have occurred in many parts of the world (Hickey, 1969). During recent years the peregrine has been placed on the list of Endangered Species. Several factors have been suggested as the cause of its decline. These include changing climatic conditions (Porter and White, 1973), human disturbance (Mattox, pers. comm.), and introduction of chlorinated hydrocarbons as pesticides into the environment (Ratcliffe, 1970). The third factor, introduction of chlorinated hydrocarbons, has occurred on the American, European and Asian continents. Even peregrines nesting in locations far from human population concentrations are exposed to chemical pollutants on migratory flights south, in nesting areas and in the wintering range. Most of the small birds utilized by the peregrine as prey in the north also migrate south every winter, many moving into farming areas where insecticides are frequently used. By feeding in these areas the passerines accumulate substantial amounts of chlorinated hydrocarbons which are stored in fat tissues. As the peregrines feed on these small birds, body levels of chlorinated hydrocarbons gradually increase. If subsequent levels·are high enough, they may cause death (Porter, 1972). In most cases, however, lethal levels are never reached: instead the lower levels produce eggshell thinning and breakage (Porter and Wiemeyer, 1969) which may be an important reason for world-wide decline in peregrine populations (Hickey and Roelle, 1969). Peregrines in the western United States have shown a 20% decrease in eggshell thickness since DDT was introduced (Enderson and Craig, 1974).
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Effects of jet aircraft overflights and other potential disturbances on behavioral responses and productivity of nesting peregrine falconsNordmeyer, Dana L. 08 April 1999 (has links)
In order to examine the potential impact of military jet overflights and other disturbances on productivity of peregrine falcons (Falco peregrinus), we observed behavioral reactions of peregrines to disturbances at nests along the Tanana River, Alaska during the 1995-1997 breeding seasons. Military jets conducted low-altitude flights over a sample of nests under observation in each year (experimental nests), while other nests were not intentionally overflown (reference nests). Other disturbances occurred at random. Animal noise monitors (ANMs), which collect and store data on noise disturbance levels, were deployed at each observed nest. A total of 878 above-threshold (��� 85 dB) overflights were recorded by the ANMs during the course of the study. A total of 401 close (defined as ��� 1000 m slant distance from the nest) overflights by subsonic F-16, F-15, A-10, Harrier, Jaguar, or Tornado jet aircraft were recorded during observations. Close overflights by military jets accounted for 63% of all observed potential disturbances at experimental nests; they accounted for 2.6% of all observed potential disturbances at reference nests. Other potential disturbances at reference nests included civilian fixed-wing aircraft (41%), boats (33%), avian predators (17%),
helicopters (5%), and mammalian predators (1%). Peregrine falcons responded
differently to animate and inanimate sources of disturbance, and responded most intensely
and most frequently to other raptors, particularly conspecifics. Flight reactions were common, but not in response to inanimate sources. Among inanimate potential disturbances, falcons responded most intensely to boats (6% of reactions involved flight), and least intensely to helicopters (3%) and fixed-wing aircraft (2%). Intensity of reactions to military jets was indistinguishable from that to either boats or other aircraft. Intense behavioral responses (including flight reactions) to military jet overflights were rarely observed in this study, even at slant distances <500 m, and no intense behavioral responses were observed at slant distances >550 m. Peregrine falcon productivity (number of fledglings produced per nesting attempt) in the study area was within the normal range for Interior Alaska and the Tanana River. Dose of jet aircraft disturbance was not correlated with productivity. Productivity was, however, negatively correlated with reactivity of both individual falcons and mated pairs. Those falcons that responded more intensely to overflights tended to have lower productivity. The sensitivity of
breeding peregrine falcons to low-altitude jet overflights is a better indicator of subsequent productivity than actual dose of overflights. This is likely a reflection of lower parental quality/investment among breeding pairs with high reactivity (i.e., younger, less experienced parents are less likely to be productive). / Graduation date: 1999
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Habitat use, dispersal and survivorship of juvenile Peregrine Falcons (Falco peregrinus) from ManitobaMartinez-Welgan, Isabel Michelle 25 April 2017 (has links)
Satellite tracking technology was used to acquire previously unavailable data relating to habitat use, dispersal and survivorship of juvenile Peregrine Falcons, a species currently designated as “Endangered” in Manitoba. A partnership between Manitoba Conservation, Manitoba Hydro, the Sustainable Development Innovations Fund of the Province of Manitoba, Parkland Mews Falconry and Bird of Prey Education Centre, and the University of Manitoba facilitated the purchase and deployment of twenty solar-powered Global Positioning System-enabled Platform Transmitting Terminals (PTTs). Thirty Peregrine Falcons were equipped with PTTs between 2011 and 2013, including both wild and hacked falcons.
Home range analysis based on kernel density estimation identified a space-filling pattern of landscape use as peregrines dispersed from the natal areas. Habitat associations determined for PTT-equipped peregrines confirm their association with open habitats, human developments and aquatic areas. Conversely, peregrines were generally not found in areas characterized by dense tree cover. Throughout the study area, juvenile falcons readily utilized human features including the support structures comprising the Manitoba Hydro Distribution and Sub-Transmission Line network.
The period following fledging and dispersal from the natal area was characterized by expansive movement quantified using a Brownian Bridge Movement Model. The importance of the natal area was evident throughout the dispersal period. Fifteen falcons (50%) survived to initiate fall migration. Of these, ten (33%) successfully reached wintering grounds located in the United States, Mexico, and Belize.
Four Peregrine Falcons were confirmed alive to project end (13%). Sixteen of 30 Peregrine Falcons were confirmed dead during the study period (53%); mortality was suspected for seven others (23%). Survivorship outcomes could not be determined for three falcons (10%). All of the observed mortality occurred during the first year of life. Although the annual production of peregrines in Manitoba currently shows an increasing trend, the population has not yet demonstrated the stability and growth to be considered secure. Ensuring a stable population will require continued active management. The provincial population may also benefit from supplementation based on delayed hack techniques. / May 2017
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Importance of wild birds in the spread of SalmonellaPalmgren, Helena January 2002 (has links)
Salmonella is one of the most important enteropathogenic bacteria. It is responsible for about 5000 reported cases of human gastroenteritis each year in Sweden. Salmonellosis is a zoonotic disease, and the bacterium has the ability to infect a variety of both domestic and wild animal species. In studies of Swedish wild bird populations, we found that Black-headed gull may be the main reservoir for Salmonella in birds, and that Salmonella infection is expressed as carriage with no obvious disease manifestations. Black-headed gull is a migratory bird and can transport strains of Salmonella with virulence traits like antibiotic resistance, from sources outside Sweden. Genetic molecular methods, PFGE and IS200, also demonstrate that Black-headed gull play a role in the transmission chain of Salmonella in Sweden. In a study of the Swedish Peregrine Falcon population, Salmonella amager and Campylobacter jejuni were found. There were indications, based on serotyping of Salmonella and genetical typing by PFGE of Campylobacter that these isolates were transmitsted to the falcons from a human or domestic animal source. This bird of prey has sparse contact with humans but may be infected by Salmonella of human origin by feeding on other birds, like gull. Salmonella was found in penguins, albatrosses and mainly in seals in a study in Antarctica. Several features of the Salmonella serotypes found indicate a human source for Salmonella infection in these animals, and also a spread of Salmonella within and between animal species in Antarctica. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 2002</p> / digitalisering@umu
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Inter- and intraspecific variation of breeding biology, movements, and genotype in Peregrine Falcon Falco peregrinus and Gyrfalcon F. rusticolus populations in GreenlandBurnham, Kurt K. January 2007 (has links)
Peregrines Falco peregrinus and Gyrfalcons F. rusticolus were studied in Low and High Arctic Greenland, comparing populations within and between areas. Analyses of weather data from northwest Greenland (1979–2005) revealed a general warming trend, resulting in a lengthened breeding window for many bird species. Both falcon species depend on cliffs for nesting, and take a similar range of bird species as prey. However, Gyrfalcons lay six weeks earlier than Peregrines in Kangerlussuaq and one month earlier than Peregrines in Thule, and occupy more sheltered nest-sites. Being larger than Peregrines, Gyrfalcons also take some larger prey species. In addition, both species move to lower latitudes for the winter, but while most Gyrfalcons migrate relatively short distances, Peregrines are complete long-distance migrants to Central and South America. One Peregrine, satellite-tracked from its breeding site at 76.5° N, travelled ~12,500 km and >100° in latitude, one of the longest migrations ever documented for a raptor. Around Thule in northwest Greenland (at 76.5° N), scientists had historically documented no breeding Peregrines, but six occupied sites were discovered during this study, comprising what is probably the most northern nesting population in the world. Over the same period, breeding Gyrfalcons have apparently disappeared from southern Greenland, and may have declined in central-west Greenland (67° N). The ultimate cause of this retraction may be climate warming, but the proximate cause is probably competition from an increasing Peregrine population. Gyrfalcons tagged with satellite-received transmitters showed characteristics associated with both obligate and facultative migration. Their winter ranges varied greatly in size, with the largest, ~172,000 km2, being the biggest ever documented for a raptor. Many individuals made long movements within a winter, and some spent up to a month at sea. They may have rested on ice and fed upon seabirds. Carbon dating of stratified faecal accumulation from Gyrfalcon nests in central-west and northwest Greenland showed use of sites for up to ~2,500 and ~650 years, respectively. The age of nest sites correlated significantly with the current distance to the Greenland Ice Sheet, and probably reflects colonization patterns following glacial retreat. In central-west Greenland the ratio of Peregrine to Gyrfalcon pairs changed from 1:1 in the early 1970s to nearly 14:1 in 2005. Over this period, competition for nest sites and prey is likely to have intensified. The crucial prey for Gyrfalcons when they start nesting in early spring are resident ptarmigan, whose numbers are probably depleted by Peregrines during the months they are present. If recent trends in climate change continue, Peregrines may continue to increase in Greenland, and spread north into areas previously occupied only by Gyrfalcons. At the same time, Gyrfalcons may retreat north from many currently-occupied areas.
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A National Park Service Internship at Acadia National ParkWilliams, John Clifford 09 May 2013 (has links)
No description available.
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