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The ecology of skylarks Alauda arvensis in grassland dominated farmlandLynas, P. January 2005 (has links)
No description available.
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GIS-based modelling of woodlark (Lullula arborea) and nightjar (Caprimulgus europaeus) habitats in a forested landscapeEvans, Mark January 2002 (has links)
No description available.
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Predicting the consequences of human disturbance, urbanisation and fragmentation for a woodlark Lullula arborea populationMallord, John W. January 2005 (has links)
No description available.
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The conservation of the short clawed-lark : Certhilauda chuanaGrosel, Joseph Ivan January 2007 (has links)
Thesis (M.Sc.)(Molecular and Life Sciences) --University of Limpopo, 2007. / The Southern African endemic Short-clawed Lark Certhilauda chuana comprises two geographically isolated populations, consisting of a western and an eastern population. Several authors have suggested that the taxonomic status of the eastern population be verified. In an attempt to resolve the taxonomic uncertainty regarding the two populations, DNA molecular data was used in a comparative study of the two populations. The DNA sequence data was generated using standard methods of DNA extraction, PCR and automated DNA sequencing for partial sequences of the mitochondrial genes Cytochrome b and ND2. A total of 530 base pairs of the Cytochrome b gene were amplified for individuals representing both Short-clawed Lark populations. The results obtained from the amplified Cyt b sequences showed the populations to be identical. The amplified partial ND2 gene (972 base pairs) showed sequence divergence between the eastern and western populations ranging between 0.10 - 0.31%. The partial ND2 gene produced only four haplotypes for both the eastern and western individuals with a single mutational step separating each of the haplotypes. The results of the DNA analysis showed that there exists very little genetic diversity within and between the two populations.
Confirmation of the taxonomic status of the two populations was supplemented by comparing selected morphometric measurements and territorial song characterization. Apart from a statistically significant difference (P < 0.05) in the length of the tarsus, there were no other significant differences in the morphometric parameters analysed. A comparison of the territorial calls of males showed considerable individual variation between males within a population and statistically significant differences between males from the two populations for some of the parameters analysed.
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The results of a habitat preference study for the eastern population was determined by analysis of the micro- and macro-habitat features within presently and historically occupied territories. It was established that as with the western population, Short-clawed Larks from the eastern population also show a fine-scale habitat preference within the broad, general habitat description of “open habitat, sparsely vegetated with small trees and shrubs”. The results of the present study explain the highly localized distribution of the species within its area of occurrence. The results also suggest that the species’ habitat preference is probably dictated as much by physiological requirements, e.g. short-grassed areas with bare ground for breeding and foraging, as it is by behavioural requirements, e.g. large open areas for aerial displays and small trees or shrubs for territorial calls.
In addition to the above, surveys were conducted to determine the species’ present extent of occurrence, area of occupancy and to obtain population size estimates. The results were compared with published data from the Southern African Bird Atlas Project and showed a dramatic range reduction of this species. Possible reasons for the range reduction include habitat loss, absence of formally protected habitat and altered ecological processes such as lack of fire and bush encroachment. It is estimated that the eastern population of the species comprise fewer than 380 breeding pairs. The observed range reduction and estimated population size suggests that the eastern population of the species requires urgent protection.
A comprehensive investigation of Short-clawed Lark vocalisations and displays was conducted. This study presents the first detailed analysis of the vocalisations of the Short-clawed Lark. Analysis of call data showed considerable variation in the number and placement of pulsed and whistle notes in their different calls. The extent of individual variation within the eastern population for the parameters analyzed, failed to reveal any dialects associated with the vocalisations of Short-clawed Larks from the eastern population. Although Short-clawed Larks call and display throughout the year and during most parts of the day, most vocalisations and displays peak in the first 1-3 hours after sunrise in the peak-breeding season. This information is useful for identification and monitoring purposes.
This manuscript concludes with a discussion of the major threats facing the population, recommendations on how to address them, and conservation priorities for the eastern population and the species. / University of Limpopo
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Aspects of the biology of the pink-billed lark (Spizocorys conirostris) in the Limpopo Province, South AfricaMathonsi, Mandlenkosi Habile Thabo January 2013 (has links)
Thesis (M.Sc. ( Zoology)) --University of Limpopo, 2013 / The fieldwork for this study was carried out from October 2008 to October 2010, under the supervision of Professor D. Engelbrecht of the Department of Biodiversity at the University of Limpopo. Professor Engelbrecht kindly agreed to provide me with raw breeding data of the same population collected during 2008. This study represents original work by the author and where work of other authors has been used; they are duly acknowledged in the text and listed as references.
Chapter 1 is a general introduction to the family Alaudidae in which their characteristics and taxonomy are discussed. This is followed by a brief overview of the general biology and ecology of larks of the world in general, followed by a more specific emphasis on the genus Spizocorys, and finally the Pink-billed Lark. In this section, gaps in the available knowledge of Pink-billed Larks are highlighted. This chapter culminates in the aim and objectives of this study. In Chapter 2 the various aspects of the breeding biology of the Pink-billed Lark are reported. This includes, amongst others, aspects such as breeding seasonality, clutch sizes, roles of the sexes during the breeding cycle and breeding success. Chapter 3 provides the results of a morphometric study of museum study skins from across the species range. This includes an analysis of sexual size dimorphism and geographical variation of the different subspecies. This chapter also provides a brief description of the timing and pattern of moult and the various vocalizations of the Pink-billed Lark. Chapter 4 concludes the dissertation with a summary of the results of this study and highlights avenues for future research on the species and the family.
The format of Chapters 2 and 3 takes the form of research papers that can be submitted for publication with minimum editing. Chapter 2 has been published in the Journal of African Zoology (see below). Chapter 3 is in preparation for submission to a peer-reviewed journal. As such, there is some repetition in the introductory paragraphs and concluding remarks of chapters 2, 3 and 4. To give this manuscript a degree of uniformity, the literature cited in all chapters has been formatted according to the manuscript requirements of the Journal of African Zoology, and a reference list appears at the end of the dissertation. Tables and figures are arranged at the end of each chapter.
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