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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.
171

Edge effects and birds across karri forest (Eucalyptus diversicolor) clear-fell edges a study of theory and conservation management /

Atkinson, Penelope Ingrid. January 2003 (has links)
Thesis (Ph. D.)--Murdoch University, 2003. / Title from PDF title page (viewed Sept. 19, 2007). Made available through Murdoch University Digital Theses Program. Includes bibliographical references.
172

Edge effects and birds across karri forest (Eucalyptus diversicolor) clear-fell edges a study of theory and conservation management /

Atkinson, Penelope Ingrid. January 2003 (has links)
Thesis (Ph. D.)--Murdoch University, 2003. / Title from PDF title page (viewed Mar. 5, 2005). Includes bibliographical references (p. 433-454).
173

Birdsong communication and perception : field and laboratory studies /

Burt, John Michael. January 1999 (has links)
Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (leaves 74-85).
174

Nest predation in riparian buffer strips in a balsam fir forest in Western Newfoundland /

Lewis, Keith P., January 1999 (has links)
Thesis (M. Sc.), Memorial University of Newfoundland, 1999. / Bibliography: p. 53-61.
175

Effects of agricultural and urban land uses on birds breeding in forest fragments near Ottawa, Ontario /

Dunford, Wendy January 1900 (has links)
Thesis (M. Sc.)--Carleton University, 2001. / Includes bibliographical references (p. 41-51). Also available in electronic format on the Internet.
176

The nonbreeding season ecology of neotropical migratory birds in the dry zone of Puerto Rico /

Baltz, Michael E. January 2000 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.
177

Phylogeography of a polymorphic southern African endemic species, the southern boubou laniarius ferrugineus (gmelin, 1788)

Molepo, Dikobe Karen January 2019 (has links)
Thesis (M.Sc. (Zoology)) -- University of Limpopo, 2019 / It cannot be overemphasised that birds, which form a group of animals that are conspicuous in many habitats, occur worldwide, and are ecologically diverse and better known than any other vertebrate groups. Some species present no geographical variation while others exhibit complex geographic variation rendering them polytypic. The Southern Boubou Laniarius ferrugineus (Gmelin, 1788) is a polymorphic and highly vocal resident species endemic to Southern Africa. It overlaps with the Tropical Boubou Laniarius aethiopicus in the extreme north of South Africa. The taxonomic circumscription presents six subspecies of L. ferrugineus which vary in size and plumage colourations. Although L. ferrugineus is of least concern (LC), its wide distribution range calls for its precise taxonomic delineation and our knowledge of its genetic structure hence the need to investigate the status and level of morphological, genetic and vocal differentiation in this species complex. Morphological, genetic and song variation were analysed from museum study skins, DNA sequences spanning one coding mitochondrial gene and three noncoding nuclear introns generated from modern and ancient samples and songs from various sound libraries respectively. While morphometric analyses and Bayesian phylogenetic inference recovered two major lineages in L. ferrugineus: 1) L. f. ferrugineus / L. f. pondoensis / L. f. natalensis (southern clade) and 2) L. f. transvaalensis / L. f. tongensis / L. f. savensis (northern clade), L. f. transvaalensis overlapped between the two lineages in MDS and Box and whisker plots. The 95% parsimony ATP6 network similarly revealed two distinct lineages with the population demographic histories of the two clades showing expansion. The divergence between the two lineages occurred approximately 1.5 million years ago during the Pleistocene epoch. Laniarius ferrugineus pondoensis is the most distinctly dark morph. The moist habitat of L. f. pondoensis could be having an effect on plumage while there is no genetic basis for the difference in plumage colouration. Almost all L. ferrugineus subspecies render a tonal song duet made up of ‘bou’ and ‘whistle’ elements with the significant difference being observed in maximum peak frequency. Laniarius ferrugineus (Gmelin, 1788) should at best be split into two species, one representing members of the southern clade to be named Laniarius ferrugineus (Gmelin, 1788) and another species representing members of the northern clade iv named Laniarius transvaalensis Roberts, 1922 based on the Principle of Priority. The current study expanded our knowledge base as far as ornithology is concerned and shed light on the phylogeographic patterns of the Southern Boubou Laniarius ferrugineus (Gmelin, 1788). The findings significantly contributed to our understanding of the evolutionary processes governing the geographical variation in Laniarius ferrugineus complex and the findings could possibly be extrapolated to other species. It was critical that the taxonomic affinities of L. ferrugineus were investigated due to its extensive distribution range for better management and conservation. Future work should further unravel the less differentiation within the south and north lineages with additional songs being analysed to understand the song pattern across the range. / National Research Foundation (NRF)
178

The mechanism of hunting by 'searching image' in birds

Dawkins, Marian Stamp January 1970 (has links)
No description available.
179

A power line risk assessment for selected South African birds of conservation concern

Smallie, Jonathan James 18 January 2012 (has links)
MSc., Faculty of Science, University of the Witwatersrand, 2011 / A selection of southern African bird species were modelled in terms of the probability of these species colliding with or being electrocuted on overhead power lines in South Africa, based on morphological and behavioral factors. Species were included in the model on the basis of internationally recognized vulnerability to these interactions at the family level. The collision model performed poorly when tested against the actual reported mortalities for species contained in the Eskom-EWT Strategic Partnership Central Incident Register CIR)(chi-square of goodness of fit) at the individual species, family and within family levels. The electrocution model performed slightly better at the family, and within family level. Both collision and electrocution models performed better for the physically larger species (and families) and for those species with higher modelled probability of collision or electrocution. As the product of random carcass detection and reporting, the CIR data are biased in various ways. Testing the models against the CIR is therefore equally important for highlighting inadequacies in the CIR, as in the model. A number of new species have emerged as being of high collision (including most importantly African Pygmy Goose, Southern Ground Hornbill, Black-bellied Bustard, Yellow-throated Sandgrouse, Caspian Tern, Hooded Vulture, Bateleur, African Marsh Harrier, Black Harrier, Pink-backed Pelican and Yellow-billed Stork) or electrocution (Southern Bald Ibis) probability in theoretical terms, and will require further investigation to determine their actual probability of interaction. By mapping the combined distributions of those species with high probabilities of collision and/or electrocution mortality, a number of priority high risk geographic areas emerge around the country.
180

Migrants in winter : carry-over effects, song, and individual success in trans-Saharan migratory birds

Sorensen, Marjorie Clements January 2015 (has links)
No description available.

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