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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.
31

Habitat requirements and conservation of the butterflies Euchloe ausonides insulanus (Pieridae) and Euphydryas editha taylori (Nymphalidae) in southwestern British Columbia

Miskelly, James William. 10 April 2008 (has links)
No description available.
32

Butterflies of the H.J. Andrews Experimental Forest : biological inventory and ecological analysis

Ross, Dana N. R. 31 October 2003 (has links)
A biological inventory of the butterflies of the H. J. Andrews Experimental Forest [HJA] in Linn/Lane County, Oregon was conducted during 1994 and 1995. It was the first comprehensive survey of HJA butterflies for the site and serves as a baseline for future butterfly research. A detailed ecological account is provided for each species documented during this and previous studies from the HJA. Patterns of butterfly richness and abundance are addressed both temporally and spatially. Within-year and between year differences in butterfly richness and abundance are explained. Butterfly richness and abundance were compared between forest, clear-cut, and meadow habitats, as well as along the roads within these habitats. Butterfly richness and abundance comparisons were also made between local butterfly hotspots and immediately adjacent areas. Lastly, the HJA butterfly fauna was compared to those of five other Oregon sites to put it into a regional perspective. Seventy-two species were recorded during this two year period and increased the total documented butterfly fauna of the HJA to seventy-nine species. Butterfly species richness was high from June through early August. Butterfly abundance increased gradually over the season and peaked in early August. Each butterfly species displayed one of four patterns of combined relative abundance and distribution: common and widespread, rare and local, common only at low elevations or common only at high elevations. The results of standardized butterfly counts suggested that subalpine meadows were much higher than clear-cuts or forests in butterfly richness and abundance, and that roads served to increase butterfly richness and abundance on a local scale in most cases. Butterfly hotspots on the HJA appear as relatively small areas of high butterfly richness and abundance and have a correspondingly high number of plant species when compared to adjacent areas. With virtually one-half of all butterfly species known for the state of Oregon, the HJA ranks among the most species-rich locations for its size within the state. This diversity originates from several biogeographical regions of origin, as defined within this study. A total of 31 HJA species have a generalized Western North American distribution, but several other biogeographical regions are also well represented. Some butterfly species appear to be at or near their geographical limits on the HJA. The assemblage of HJA butterfly species is virtually inclusive of those from Mary's Peak and McDonald Forest in northwestern Oregon, whereas it differs by 30% or more from the more biogeographically distinct faunas of Crater Lake National Park, Mount Ashland and Steens Mountain. Future butterfly work on the HJA is recommended. Oregon butterfly distribution maps suggest that several additional butterfly species should be found there. More biogeographical analyses combined with long term monitoring of HJA butterflies could help to both predict and document changes in the Pacific Northwest butterfly fauna due to human disturbance and global climate change. / Graduation date: 2004
33

Testing the Effectiveness of Citizen Science Using a Volunteer Butterfly Monitoring Program

Moore, Charlotte January 2014 (has links)
An increasingly popular method of collecting scientific data is to use citizen scientists in community-based monitoring programs. Numerous formal and community-based monitoring programs use butterflies as indicator species to detect and understand changes in ecosystems. A butterfly monitoring program was established with the City of Kitchener in 2012, in order to measure the effectiveness of citizen science observations in identifying butterfly assemblages. Two monitoring sites were used: Lakeside Park contained relatively simple butterfly habitats, and Huron Natural Area which included complex butterfly habitats. The program consisted of training volunteers to collect data on the butterfly assemblages. Volunteers were given the choice to monitor an established trail at either natural area once every two weeks from the beginning of May to the end of August using the modified Pollard method. It was important to train volunteers how to monitor butterflies, so they were required to attend an instruction workshop to learn the methods to be employed, identification of butterflies, use of the recording form, and proper net and butterfly handling techniques. Quality control measures were another important component of the program, and included comparing volunteer observations at each natural area to those collected by an expert. Each species observation was reviewed to determine the likelihood of the species observation. The species and its habitat were compared to the information and status recorded in The Butterflies of Waterloo Region. The data collected by the participants was analyzed separately by study site and included the calculation of species richness, Shannon-Wiener Diversity Index (H), evenness value, Simpson Index (D), and Simpson Reciprocal (1/D) values. A two-tailed t-test was conducted to compare the data (as represented by Shannon indexes) collected by volunteers and the expert. The species richness for Lakeside Park was 29, which was slightly higher than the 26 species identified at Huron Natural Area. However, the Shannon-Wiener Diversity Index (H), evenness value (E), Simpson Diversity Index (D), and Simpson Reciprocal Index (1/D) all demonstrated that there was a more even and diverse butterfly population at Huron Natural Area than at Lakeside Park. A high level of validity of volunteer observations was found during this study, as 93% of submitted observations at Lakeside Park and 94% of submitted observations at Huron Natural Area passed the review process. Based on the high level of validity of observations it was determined that the volunteers were successful in characterizing butterfly assemblages, and establishing baseline conditions at each site. The City of Kitchener will be collecting long-term butterfly data, which they can compare over time to provide insight into the diversity at these natural areas. This research program has contributed to the field of science and to the literature by establishing a review process for citizen science, particularly for butterfly programs. It has also provided further validation of citizen science data.
34

Reflection and absorption of light in butterfly wing scales /

Zeng, Zheng. January 2008 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2008. / Includes bibliographical references (leaves 62-63). Also available in electronic version.
35

Modeling landscape change and evaluating ecological effects of landscape composition and configuration in northern Idaho /

Pocewicz, Amy Lynne. January 1900 (has links)
Thesis (Ph. D.)--University of Idaho, November 2006. / Major professor: Penelope Morgan. Abstract. Includes bibliographical references. Also available online in PDF format.
36

Mění se párovací chování denních motýlů s fenologickým stavem populací? / Does butterfly mating behaviour change with phenological condition of populations?

VLAŠÁNEK, Petr January 2008 (has links)
The optimization theory assumes that males of insects with separate adult generations should preferentially invest into the mating if there are the most fresh females; in other times they should save energy and focus on maintenance activities. Based on this assumption, butterfly behaviour should change with season, population density (mainly the sex ratio) and day time. To explore these assumptions, we used mark recapture data obtained from several mark-recapture studies, which contained records of behaviour of each handled individual. In total, we analysed data on 14 species, 24 ``butterfly-seasons{\crqq}, 21 737 individuals (14 228 males, 7 509 females). We subjected the behavioural data to ordination analyses controlled for weather effects. For daily patterns, morning and afternoon activities comprise mainly of maintenance activities, while mating seems to occur in middays. Regarding seasonal patterns, males of most of the species switched from mating behaviour to maintenance behaviour. No prevailing trend applied to females, in which we found both transitions from mating behaviour to maintenance activities and opposite patterns. Density predictors (sex ration, daily population size) revealed changes in mating behaviour of one sex with changing the abundance of the other sex. In conclusion, exploring mark-recapture data for behavioural patterns proved to be fruitful, but cannot fully replace studying behaviour via more traditional ethological methods.
37

The adaptive value of melanism in alpine Colias butterflies (Lepidoptera:Pieridae)

Roland, Jens January 1981 (has links)
Many insect populations become darker at high elevations and high latitudes. Despite absence of empirical evidence, it is commonly believed that melanism allows more efficient basking by insects in sunlight, thereby raising body temperature and increasing activity. Variation in melanism within a single population of alpine Colias sulphur butterflies (Lepidoptera:Pieridae) allowed determination of the advantage, in cold environments, for this characteristic. Alternative hypotheses relating the effect of melanism to fecundity, predation, diel activity, and seasonal survivorship were tested by field and laboratory observation and experiment. At low temperature, melanistic females are more fecund. A balancing advantage for light coloured females does not exist at high temperatures. Dark individuals suffer lower predation rates at high altitude than do light individuals; the opposite is not true at low elevation. Duration of diel activity is markedly extended for darker butterflies under cool conditions, but only slightly for light individuals during warm sunny periods. Melanistic individuals are able to prolong the duration of activity for feeding, mate location, oviposition and escape from predation under cold conditions. This appears to the prime benefit for melanism in this population. This is the first demonstration, in a natural population, of the benefit of alpine melanism in insects. / Science, Faculty of / Zoology, Department of / Graduate
38

Preference and performance in a population of checkerspot butterflies with known diet history

Hasanah, Nur 14 February 2011 (has links)
This thesis describes a relationship between maternal preference and offspring performance in a population of the butterfly Euphydryas editha that used two host plants, Pedicularis semibarbata and Collinsia torreyi from 1979 to 2001, but now no longer uses Collinsia. In the light of the known history of diet change in this butterfly population, it is not surprising that maternal oviposition preference was variable. Although the diet of the butterflies that evolved rapidly in the 1980’s is no longer changing, I still discovered some females with a chemical preference for Collinsia. This seems to be a legacy of recent anthropogenic diet evolution. The evolution of host preference of females in Rabbit Meadow has not finished yet. Variation of offspring weight and survival were measured and showed a complex relationship with adult preference. Although quite a few adults strongly rejected Collinsia, their offspring grew well on this host, and there was no significant trend for the offspring of strongly Pedicularis-preferring butterflies to perform more poorly on Collinsia. / text
39

An analysis of climate induced hybrid speciation in Tiger Swallowtail butterflies (Papilio)

Ording, Gabriel J. January 2008 (has links)
Thesis (Ph. D.)--Michigan State University. Dept. of Entomology, 2008. / Title from PDF t.p. (viewed on Mar. 30, 2009) Includes bibliographical references (p. 154-165). Also issued in print.
40

Comparative phylogeography of five swallowtail butterfly species (Lepidoptera: Papilionidae) in South Africa : ecological and taxonomic implications.

Neef, Götz-Georg January 2014 (has links)
With current biota under constant threat of extinction, it is important to ascertain where and how biological diversity is generated and partitioned. Phylogeographic studies can assist in the identification of places and processes that indicate the origin and maintenance of biodiversity. Forest fragmentation has a big effect on local extinction and loss of genetic diversity of forest-restricted taxa, along with divergence and speciation of forest biota. This study aims to understand the effects of these processes on a number of forest-dwelling butterflies using a comparative phylogeographic approach. Mitochondrial DNA of five different Papilio species with different degrees of forest specificity was analysed using phylogenetic methods. In addition, the subspecific taxonomy of P. ophidicephalus was investigated using morphometrics of discal spots on the wings and nuclear DNA analysis along with mitochondrial DNA analysis. The results show that the forest-restricted species (P. ophidicephalus and P. echerioides) have more genetic structure and less genetic diversity than the more generalist species (P. dardanus, P. demodocus and P. nireus). This could be due to inbreeding depression and bottlenecks caused by forest fragmentation. As forest patches become smaller, the population size is affected and that causes a loss in genetic diversity, and increasing habitat fragmentation disrupts gene flow. The intraspecific taxonomy of P. ophidicephalus is far from revealed. However, this study shows there is evidence for the different subspecies when comparing morphological results and genetic results. From the evidence provided here it is suggested that P. ophidicephalus should be divided into two separate species rather than five subspecies.

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