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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.
1

Effects of fire on the distribution and abundance of Sprague's pipit (Anthus spragueii) and their invertebrate prey.

Champagne, Janessa 13 September 2011 (has links)
The Sprague’s pipit is a small, threatened grassland songbird endemic to the Canadian prairies and to the northern Great Plains of the United States. Between 1968 and 2006, the population of Sprague’s pipit in Canada experienced a significant annual decline of 4.5%. The prairie provinces also experienced declines within this reporting period. Pipits are more abundant in native prairie grasslands, however much of their preferred habitat has been lost due to the influence of human activities. Furthermore, management of remaining grasslands has impacted the quality of habitat through suppression of natural disturbances such as fire. Few studies have addressed how fire affects the occurrence and abundance of Sprague’s pipit, thus pipit response to fire is poorly understood. This study investigated the effect of fire on the density and distribution of Sprague’s pipit in south-western Manitoba by examining the associations between pipit density, invertebrate food resources and vegetation structure with fire history. Surveys to determine pipit abundance, invertebrate resources and vegetation structure were conducted in 2007; in 2008 only pipit abundance and vegetation surveys were conducted. Although there was no significant effect of invertebrate resource abundance on Sprague’s pipit density, the abundance of grasshoppers and ground beetles declined with increasing time since last burn, which suggests that longer fire-return intervals may reduce the availability of these prey species for pipits. Fire did not significantly influence the distribution and density of Sprague’s pipit in this region. However the response of the vegetation to fire may indicate that the existing fire-return interval is not contributing to the population decline of Sprague’s pipit, but that in the absence of fire, the habitat could regress to a state that does not meet the critical habitat needs of this species.
2

Effects of fire on the distribution and abundance of Sprague's pipit (Anthus spragueii) and their invertebrate prey.

Champagne, Janessa 13 September 2011 (has links)
The Sprague’s pipit is a small, threatened grassland songbird endemic to the Canadian prairies and to the northern Great Plains of the United States. Between 1968 and 2006, the population of Sprague’s pipit in Canada experienced a significant annual decline of 4.5%. The prairie provinces also experienced declines within this reporting period. Pipits are more abundant in native prairie grasslands, however much of their preferred habitat has been lost due to the influence of human activities. Furthermore, management of remaining grasslands has impacted the quality of habitat through suppression of natural disturbances such as fire. Few studies have addressed how fire affects the occurrence and abundance of Sprague’s pipit, thus pipit response to fire is poorly understood. This study investigated the effect of fire on the density and distribution of Sprague’s pipit in south-western Manitoba by examining the associations between pipit density, invertebrate food resources and vegetation structure with fire history. Surveys to determine pipit abundance, invertebrate resources and vegetation structure were conducted in 2007; in 2008 only pipit abundance and vegetation surveys were conducted. Although there was no significant effect of invertebrate resource abundance on Sprague’s pipit density, the abundance of grasshoppers and ground beetles declined with increasing time since last burn, which suggests that longer fire-return intervals may reduce the availability of these prey species for pipits. Fire did not significantly influence the distribution and density of Sprague’s pipit in this region. However the response of the vegetation to fire may indicate that the existing fire-return interval is not contributing to the population decline of Sprague’s pipit, but that in the absence of fire, the habitat could regress to a state that does not meet the critical habitat needs of this species.
3

Effects of natural gas development on three grassland bird species in CFB Suffield, Alberta, Canada

Hamilton, Laura Elizabeth. January 2010 (has links)
Thesis (M. Sc.)--University of Alberta, 2010. / Title from pdf file main screen (viewed on Jan. 22, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Ecology, Department of Biological Sciences, University of Alberta. Includes bibliographical references.
4

Individuální akustický monotoring pěvců na příkladu lindušky lesní / Individual acoustic monitoring of songbirds - case study on the tree pipit

Pišvejcová, Iveta January 2014 (has links)
In field behavioural and ecological studies, it is often necessary to identify specific individuals. In birds, colour rings are often used as individual marks. However, rings might be difficult to observe, especially in small species and dense habitats. Thus recently, individual acoustic monitoring is becoming more commonly used to study of birds. This method is based on the recognition of individuals and often on the difference between temporal and spectral parameters of their vocalizations. However, in passerine species with more complex song these acoustic characteristics may not be reliable. In my thesis I used an alternative approach for the individual acoustic monitoring, based on differences in syllable repertoires of individual Tree Pipit males (Anthus trivialis). So far I have not found any study that would use a similar approach with other migratory passerine species with more complex song. The main aim of my study was to test the possibility of using syllable repertoires for recognition of specific individuals and to determine if this method is more efficient than identification by colour banding. From four years of research on the Tree Pipits population in the selected location in Brdy I received acoustic data from 59 males that I subsequently analyzed in a bioacoustic program. The...
5

Effects of natural gas development on three grassland bird species in CFB Suffield, Alberta, Canada

Hamilton, Laura 06 1900 (has links)
I investigated the effect of energy sector development and introduced crested wheatgrass (Agropyron cristatum) on grassland birds on Canadian Forces Base Suffield. I conducted point counts and mapped breeding territories in 2007 and 2008 for Savannah sparrows (Passerculus sandwichensis), chestnut-collared longspurs (Calcarius ornatus), and Spragues pipits (Anthus spragueii). I found that Savannah sparrows favored areas with taller vegetation, human disturbances and crested wheatgrass in both years. Longspurs used shorter vegetation and in were tolerant of disturbance. Crested wheatgrass was avoided by longspurs in both years. Pipit territories contained similar vegetation to longspurs, were sensitive to disturbance, and avoided placing territories in areas containing crested wheatgrass or trails in both years. Well sites, pipelines and junctions were not avoided by the three species. My research suggests that reducing the number of trails and the spread of crested wheatgrass will increase habitat availability for sensitive species of grassland birds. / Ecology
6

Effects of natural gas development on three grassland bird species in CFB Suffield, Alberta, Canada

Hamilton, Laura Unknown Date
No description available.
7

Dynamika habitatů lindušky úhorní na severočeských hnědouhelných výsypkách / Habitat dynamics of Tawny pipit on the coal dumps in Northern Bohemia

Bernhäuserová, Veronika January 2019 (has links)
Surface mining and its associated territory disturbance is generally perceived negatively by society. However, these newly transformed regions may be very important areas of conservation from biodiversity point of view of and emergence of refugia. This thesis investigates the dynamics of the coal dumps and the land cover changes in relation to the occurrence of endangered species of Tawny pipit (Anthus campestris) in the North Bohemia. This area is the only breeding region in the country for this species. The aim of this thesis is to describe land cover change on three coal dumps (Tušimice, Bílina a Vršany) within horizon of four years (2014, 2015, 2016 and 2017). Moreover, another aim was to asses habitat preferences of Tawny pipit based on ornithological findings for particular year. As it is seen from the results, the most significant change occurred at those areas, which were without vegetation cover in the beggining of monitoring and were cover with vegetation later. The category of herbal vegetation was the one which increased the most, as it was caused by spontaneous succession. It showed up that Tawny pipit's most preferred areas are land cover categories coal dumps surface without vegetation, coal dumps surface with herbal vegetation and category buildings, build-up area and transport...
8

From relict to future model? Common pastures as biodiversity refuges in the pre-alpine agricultural landscape

Schwarz, Cinja 10 May 2022 (has links)
Wir befinden uns inmitten einer globalen Biodiversitätskrise mit steigender Aussterberate, die die natürliche Hintergrundrate bereits jetzt um das Tausendfache überschreitet. In terrestri-schen Lebensräumen geht vom Landnutzungswandel die größte Gefahr für die Biodiversität aus. Besonders die ursprünglich hohe Vielfalt im mitteleuropäischen Grünland ist seit der In-dustrialisierung durch Nutzungsintensivierung und -aufgabe stark zurück gegangen. Traditionell genutztes, beweidetes Grünland ist in Mitteleuropa selten geworden. Dennoch deuten einige aktuelle Studien auf seine große Bedeutung für den Erhalt der Biodiversität in der Agrarland-schaft hin. Allerdings fehlen umfassende, systematische Untersuchungen für viele traditionelle Grünlandsysteme. Um diese Wissenslücke zu verringern, untersuchte ich in meiner Dissertation die Relevanz voralpiner, traditionell bewirtschafteter Allmendweiden als Refugium für bedrohte Zielarten (Baumpieper [Anthus trivialis], Blaukernauge [Minois dryas]) sowie für arten- und individuenreiche Zoozönosen (Heuschrecken [Orthoptera]) der mitteleuropäischen Agrarlandschaft. Gepaarte Vergleiche von Allmendweiden und angrenzenden Flächen mit identischen Standortbedingun-gen (Referenzflächen) ermöglichten den Vergleich der Arten bzw. -gruppe anhand von Umwelt-parametern in den Vegetationstypen Grünland auf Mineralboden und offenen Mooren. Der Un-tersuchungsraum in Südbayern stellt den Verbreitungsschwerpunkt für Allmendweiden und intakte bis naturnahe Moorökosysteme in Deutschland dar. Meine Analysen zeigen, dass sich der Landnutzungswandel drastisch auf die Referenzflä-chen, die früher überwiegend Teil der Allmendweiden waren, auswirkte: Im Vergleich zu den Weiden weisen sie (i) homogene Strukturen auf Landschafts- und Habitatebene, (ii) geringe Anteile nährstoffarmer Habitate und (iii) eine geringe Besiedlung von Vögeln und Insekten auf. Somit sind sie weitgehend ungeeignet für den Erhalt der Biodiversität. Die einzige Ausnahme innerhalb der Referenzflächen bilden traditionell genutzte Heu- und Streuwiesen. In den Allmendweiden sorgt die traditionelle Beweidung (0.5–2.0 Großvieheinheiten/ha von Mai–Oktober) für eine hohe strukturelle Vielfalt mit nährstoffarmen Habitaten und fließende Übergänge zwischen Wald und Offenland. So können saisonal bzw. innerhalb des Lebenszyklus wechselnde Ansprüche vieler typischer Agrarlandschaftsarten im eng verzahnten Mosaik wert-voller Habitate erfüllt werden. Der Erhalt der Allmendweiden ist für das Überleben von Agrar-landschaftsarten im Untersuchungsgebiet essenziell. Eine Ausdehnung der Allmendweiden-Nutzung auf angrenzende Flächen ist unbedingt zu empfehlen.

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