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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.
11

The behavioural effects of formamidine pesticides in Lepidoptera

Blackwell, Alison January 1987 (has links)
No description available.
12

The ecology and population structure of a butterfly cline

Melling, T. M. January 1987 (has links)
No description available.
13

Butterfly Community and Behavioral Responses to Restored Disturbance Regimes

Karasch, Brooke January 2020 (has links)
Grassland organisms evolved alongside the interaction of fire and grazing, but modern management often decouples these disturbances. In order to analyze the effects of reintroducing this interaction, we implemented four treatments. Two of these treatments were variations of patch-burn grazing, one was modified rest-rotation grazing, and one was season-long grazing. We chose to monitor the butterfly response to these treatments because butterflies have short generations, require a wide variety of resources, and are easily identifiable as adults. We quantified both the butterfly community and the behavioral time budgets of two species. We found that the butterfly community is more species-rich and abundant in treatments including fire than in treatments without fire. We found no difference in time budgets between treatments. Overall, we suggest that managers implement a carefully-planned patch-burn grazing regime in order to support grassland butterflies and other organisms.
14

The morphology, pigmentation, and development of structural coloration in Vanessa cardui (Lepidoptera: Nymphalidae)

Shelby, Emily A 13 December 2019 (has links)
Butterfly wing color patterns are produced by the placement of monochromatic scales that have specific colors due to pigmentation, nanostructures, or a combination of both. Structural coloration results from the interference of light from the architecture of the nanostructures. Structural coloration in butterfly scales has been studied optically, but little is known about the mechanisms used to create these scales compared to scales without structural coloration. Light, scanning, and transmission electron microscopy were used to determine underlying morphological, pigmentation, and developmental differences between blue (i.e., structural) and black (i.e., nonstructural) wing scales of Vanessa cardui. Differences in scale size, pigmentation, nanostructure spacing, and cuticle deposition were identified as contributors to structural coloration in mature scales. Differences in cuticle deposition, trabeculae formation, and longitudinal ridge spacing were identified during development. Differences in cuticle deposition during scale development were implicated as an influential factor for the production of structural coloration.
15

STROKE LENGTH, STROKE FREQUENCY AND VELOCITY OF MALE AND FEMALE SWIMMERS IN THE BUTTERFLY.

Stevens, Margaret Gail. January 1983 (has links)
No description available.
16

The sublethal effects of DDT and two other insecticides on Pieris brassicae L

Bushara, A. G. January 1981 (has links)
No description available.
17

Plant communities in oak savannahs in Ontario : are we ready for reintroduction of the Karner Blue Butterfly (Lycaeides melissa samuelis)? /

Chan, Pak Kin. January 2004 (has links)
Thesis (M.Sc.)--York University, 2004. Graduate Programme in Biology. / Typescript. Includes bibliographical references. Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ99289
18

Butterfly cartilage inlay graft myringoplasty at Chris Hani Baragwanath hospital (2009 - 2013)

Morgado, Natasha January 2017 (has links)
Research Report submitted to the Faculty of Health Sciences, University of the Witwatersrand, in partial fulfilment of the requirement for the Degree of Masters of Medicine in Otorhinolaryngology Johannesburg October 2017 / AIM: This study aimed to assess the anatomical and functional success rate of Butterfly Cartilage Inlay Graft myringoplasties done at Chris Hani Baragwanath Academic Hospital using an oto-endoscope. Size of perforation was assessed as a possible predictor of success. METHODS: The study comprised of a retrospective review of all records from the ENT Department at Chris Hani Baragwanath Academic Hospital of all patients who underwent BCIG myringoplasty from January 2009 to December 2013. 85 of the 160 patients who had BCIG’s at CHBAH met the inclusion criteria for this study. Data was collected on a data collection sheet and analysed using standard statistical methods. RESULTS: 85 patients were included in the study of ages 5 years – 67 years with a mean age (SD) of 19,2 years (16,3). 61% were children (<13 years), 39% adults (14 – 49 years) and only 6% were >50 years. There were 30 (35%) Female patients and 55 (65%) Male patients. The data presented in this study show an anatomical success rate of 90,6% for Butterfly Cartilage Inlay Grafts at Chris Hani Baragwanath Academic Hospital. The anatomical success rate of this study is equal to the success rates reported in the literature for the same procedure. 87% of patients experienced hearing improvement post operatively. The average hearing improvement in this study post Butterfly Cartilage Inlay Graft is 15dB. Finally, perforation size does not influence both anatomical and functional success rates in this study. CONCLUSION: Endoscopic BCIGs performed at Chris Hani Baragwanath Academic Hospital, for small, medium and large perforations, show anatomical and functional success rates similar to those reported in the literature, performed with both microscope and endoscope. Size of perforation is not a predictor of anatomical and functional success for this procedure. / MT2018
19

Ecology and conservation of the butterfly Thestor brachycerus brachycerus (Trimen, 1883) from the Western Cape / Elizabeth Ann Bazin

Bazin, Elizabeth Ann January 2015 (has links)
The 1883 discovery, research into generic life histories and taxonomic investigations into the aphytophagous butterfly Thestor brachycerus brachycerus (the Knysna Skolly) from Knysna, South Africa are described. Its slide towards extinction through loss and degradation of habitat in the late 20th century left only one known colony by 2009 leading to it being assessed as Critically Endangered in the 2013 South African Red List and Atlas. During searches for more populations in 2011, a second T. b. brachycerus colony was found which differed markedly with respect to aspect, altitude and vegetation. Study areas were defined around the original colony on the Pezula Golf Estate (Pezula) and the newly discovered coastal colony east of Coney Glen (Coastal site). An assessment is made of the ecological differences and similarities between the two sites. The extent and size of the two known populations was measured; the Extent of Occupancy was found to be 7.5 km2 and the Area of Occupancy as 1.05 x 10-3 km2. During observations over 5 seasons in December and January 2009 – 2014 the average number of butterflies observed at the original Pezula colony varied from 1 – 8 males and 0 – 3 females per survey, compared with 1 – 6 males and 1 – 3 females observed over 3 seasons from 2011 to 2014 at the Coastal colony. The mating, territoriality, oviposition and predation avoidance behaviour of the adult T. b. brachycerus butterflies was studied by direct observation. Males were found to exhibit territorial behaviour, spending long periods of time perched in one spot, particularly in areas where the vegetation was open or low. Oviposition was rapid and no preference was shown by females for any particular plant. Between the two colonies, oviposition was observed on a total of 16 different plants. The vegetation composition at the two study sites was analysed using Braun–Blanquet methodology. Only one plant, Tarchonanthus littoralis, was found to be common to both. There appeared to be no correlation between floristic composition and the occurrence of T. b. brachycerus. All the Thestor species so far studied by other workers have been found to be myrmecophilous, having an association with the pugnacious ant Anoplolepis custodiens. Ant communities were sampled by employing pitfall traps and direct sampling by hand. At both the Pezula and Coastal sites A. custodiens was the most ubiquitous ant species. The insights gained have enabled implementation of a habitat management plan. Experimental management methods are recommended at the Pezula site which include small scale burning and selective cutting of vegetation. Search for more colonies is ongoing, using the improved ecological knowledge of the butterfly. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015
20

Ecology and conservation of the butterfly Thestor brachycerus brachycerus (Trimen, 1883) from the Western Cape / Elizabeth Ann Bazin

Bazin, Elizabeth Ann January 2015 (has links)
The 1883 discovery, research into generic life histories and taxonomic investigations into the aphytophagous butterfly Thestor brachycerus brachycerus (the Knysna Skolly) from Knysna, South Africa are described. Its slide towards extinction through loss and degradation of habitat in the late 20th century left only one known colony by 2009 leading to it being assessed as Critically Endangered in the 2013 South African Red List and Atlas. During searches for more populations in 2011, a second T. b. brachycerus colony was found which differed markedly with respect to aspect, altitude and vegetation. Study areas were defined around the original colony on the Pezula Golf Estate (Pezula) and the newly discovered coastal colony east of Coney Glen (Coastal site). An assessment is made of the ecological differences and similarities between the two sites. The extent and size of the two known populations was measured; the Extent of Occupancy was found to be 7.5 km2 and the Area of Occupancy as 1.05 x 10-3 km2. During observations over 5 seasons in December and January 2009 – 2014 the average number of butterflies observed at the original Pezula colony varied from 1 – 8 males and 0 – 3 females per survey, compared with 1 – 6 males and 1 – 3 females observed over 3 seasons from 2011 to 2014 at the Coastal colony. The mating, territoriality, oviposition and predation avoidance behaviour of the adult T. b. brachycerus butterflies was studied by direct observation. Males were found to exhibit territorial behaviour, spending long periods of time perched in one spot, particularly in areas where the vegetation was open or low. Oviposition was rapid and no preference was shown by females for any particular plant. Between the two colonies, oviposition was observed on a total of 16 different plants. The vegetation composition at the two study sites was analysed using Braun–Blanquet methodology. Only one plant, Tarchonanthus littoralis, was found to be common to both. There appeared to be no correlation between floristic composition and the occurrence of T. b. brachycerus. All the Thestor species so far studied by other workers have been found to be myrmecophilous, having an association with the pugnacious ant Anoplolepis custodiens. Ant communities were sampled by employing pitfall traps and direct sampling by hand. At both the Pezula and Coastal sites A. custodiens was the most ubiquitous ant species. The insights gained have enabled implementation of a habitat management plan. Experimental management methods are recommended at the Pezula site which include small scale burning and selective cutting of vegetation. Search for more colonies is ongoing, using the improved ecological knowledge of the butterfly. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015

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