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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.
51

Impact of wildfire on the spotted-tailed quoll Dasyurus maculatus in Kosciuszko National Park

Dawson, James Patrick, Physical, Environmental & Mathematical Sciences, Australian Defence Force Academy, UNSW January 2005 (has links)
A population of spotted-tailed quolls Dasyurus maculatus was studied for three years (2002-2004) in the lower catchment of the Jacobs River, in the Byadbo Wilderness Area of southern Kosciuszko National Park, south-eastern New South Wales, Australia. Survey and monitoring of quoll latrine sites and prey populations, dietary analysis and live-trapping was carried out for one year before and two years after the widespread wildfires of January 2003, which had a very high impact on the study area. Survey for spotted-tailed quoll latrine sites was successful in locating a total of 90 latrine sites in the Jacobs River study area over the three years of the study. These were found throughout all parts of the topography among large, complex granite outcrops and along rocky sections of riparian habitat. After the fire in 2003, lower numbers of latrines were in use than observed pre-fire, and there was a lower level of usage (number of scats) of individual latrines. Continued monitoring in 2004 revealed that many latrines that had become inactive in 2003 following the fire were re-activated in the second breeding season following fire. 1466 spotted-tailed quoll scats were collected from latrines and live-trapped quolls over the three years of the study. Hair analysis from scats identified twenty-two different species of mammal in the diet of the spotted-tailed quoll from the Jacobs River study area, representing the majority of all prey identified (98.5% occurrence) and contributing almost all of the biomass consumed (99.6%). Medium-sized mammals were the most important prey category, followed by small mammals, large mammals (most likely taken as carrion) and non-mammalian prey (birds, reptiles, insects and plants). Brushtail possums were the most important single prey item by both frequency of occurrence and percentage biomass in all years, followed by lagomorphs (rabbits and hares), Rattus spp., and swamp wallabies. There was a significant difference in the composition of the diet by major prey category across the years of the study as a result of the fire, indicated by a shift in utilisation of food resources by quolls in response to significant changes in prey availability. Monitoring of prey populations revealed that brushtail possums, lagomorphs and bandicoots were all significantly less abundant in the study area in the winter directly following the fire, followed by a significant increase in abundance of lagomorphs, but not of possums, in the second winter after the fire. Quolls adapted well to this altered prey availability. While there was a significant decrease in occurrence of brushtail possum in scats after the fire, significantly more scats contained hair of lagomorphs, to the point where almost equal proportions of lagomorphs and possum hair occurred in scats by the winter of 2004. Other fire-induced changes to the diet were evident, such as a significant drop in the occurrence of small mammals in scats for both winters after the fire, and a peak in occurrence of large mammals in the winter directly following the fire that strongly suggests there was a short-term increase in the availability of carrion. A large, high-density population of spotted-tailed quolls was live-trapped and marked during the winter breeding season of 2002. Twenty-two quolls (13 male and 9 female) were present in the study area in 2002, and subsequent trapping over the 2003 and 2004 winter breeding seasons following the fire revealed that the high-intensity wildfire did not result in the extinction of the local population. There was evidence of a small, short-term decline in the number of quolls present in the study area in the 2003 breeding season, with 16 individual quolls captured. Males were outnumbered two-to-one by females, due either to mortality or emigration. Trapping in 2004 showed a recovery of the population to numbers exceeding that observed prior to the fire, with 26 individuals captured (16 male, 10 female), most likely as a result of immigration. There was some evidence that recruitment of young from the post-fire breeding season in 2003 was reduced because of the fire. This study took advantage of an unplanned wildfire event to monitor the response of a population of spotted-tailed quolls and their prey. In this regard it was fortuitous since it has been recognised that the use of replicates and controls in the study of the impacts of wildfire on such species is likely to be logistically impossible. Consequently, the effects of fire on forest and woodland fauna such as the spotted-tailed quoll are poorly understood, with many authors expressing concern that, potentially, wildfires are likely to be highly detrimental to resident quoll populations. The results of this study, however, concur with the few other studies in which forest mammal populations have been monitored before and after wildfire in suggesting that wildfires may not be as destructive to fauna as that imagined. The results of this work will provide information to assist in the preparation of management strategies for the species, such as recovery plans, as well as information for land managers preparing management plans, including fire management plans, for habitats in which spotted-tailed quolls are found throughout their range.
52

Atividade repelente e inseticida do pó de plantas medicinais sobre o caruncho do Feijão-caupi. / Repellent and insecticidal activity of the medicinal plants powder on the cowpea beetle.

LEITE, Camila Maria Formiga. 28 May 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-05-28T15:31:34Z No. of bitstreams: 1 CAMILA MARIA FORMIGA LEITE - DISSERTAÇÃO PPGSA PROFISSIONAL 2016..pdf: 1330991 bytes, checksum: 3763a8f8c7326718476ac867c8c63cb6 (MD5) / Made available in DSpace on 2018-05-28T15:31:34Z (GMT). No. of bitstreams: 1 CAMILA MARIA FORMIGA LEITE - DISSERTAÇÃO PPGSA PROFISSIONAL 2016..pdf: 1330991 bytes, checksum: 3763a8f8c7326718476ac867c8c63cb6 (MD5) Previous issue date: 2016-12-15 / O feijão-caupi representa uma fonte de alimento estratégica pelos altos teores de proteínas, carboidratos e de sais minerais e adaptação às condições ambientais adversas. Existem pragas capazes de atacar grãos/feijão armazenados, e a mais importante dessas no Brasil é o Callosobruchus maculatus (Coleoptera: Bruchidae), destacando-se por atacar sementes perfeitas, devido ao seu potencial depreciativo, trazendo má qualidade aos grãos e consumindo as reservas de nutrientes do embrião. O método de controle mais utilizado contra pragas de armazenamento é o uso de produtos químicos de distintas classes toxicológicas. Embora esses produtos tenham bastante eficiência, seu uso intensificado pode acarretar em problemas, com isso a utilização das plantas com atividade inseticida tornou-se tão importante, sendo geralmente aplicados na forma de pós, extratos ou óleos. Diante do exposto, este trabalho teve como objetivo avaliar o efeito repelente e inseticida de ervas utilizadas na cultura popular como medicinais no controle de Callosobruchus maculatus em grãos de feijão-caupi (Vigna unguiculata L.) em condições de laboratório, analisando a dose letal (DL50) e tempo letal (TL50) desses carunchos em relação ao pó dessas erva medicinais (Melissa officinalis (erva cidreira), Peumus boldus (boldo-do-chile), Maytenus ilicifolia (espinheira-santa), Mentha (hortelã). O experimento foi conduzido no laboratório de Entomologia da Universidade Federal de Campina Grande (UFCG), Campus Pombal, Paraíba, Brasil. Os grãos de feijão-caupi foram tratados com os pós nas concentrações de 5,0 g e em doses diferenciadas de 0,25, 0,50, 0,75 e 1,0 % (massa do pó/massa de grãos) e realizados testes de preferência e sobrevivência contra C. maculatus. No que se refere à repelência Erva cidreira, Boldo-do-chile e a Hortelã os insetos exibiram propriedades repelentes, melhor especificando os insetos não tiveram preferência pelas mesmas. Já com a Espinheira Santa, os insetos mostraram-se atraentes/preferentes. No que se referem à sobrevivência todas as espécies causaram mortalidade, em determinado período de tempo. / The Cowpea represents a strategic food source for the high levels of proteins, carbohydrates and mineral salts and adaptation to adverse environmental conditions. There are plagues capable of attacking grains/beans stored, and the most important of these in Brazil is the Callosobruchus maculatus (Coleoptera: Bruchidae), stand out to attack perfect seeds due to its derogatory potential, bringing bad quality grains and consuming nutrient reserves of the embryo. The most widely used control method against pests is the use of chemical products of different toxicological classes. Although these products have a lot of efficiency, its use can cause problems if it’s intensified, then the use of plants with insecticidal activity became so important, being generally applied in the form of powders, extracts or oils. On the exposed, this work aimed to evaluate the effect of insecticide and repellent herbs used in popular culture as the medical control of Callosobruchus maculatus in Cowpea beans, (Vigna unguiculata L.) under laboratory conditions, analyzing the lethal dose (Ld50) and lethal time (TL50) of these weevils in relation to those medicinal herb powder (Melissa officinalis (balm), Peumus boldus (boldo), Maytenus ilicifolia (espinheira-santa), Mentha (Mint). The experiment was conducted in the laboratory of Entomology, Federal University of Campina Grande (UFCG), Campus Pombal, Paraíba, Brazil. Cowpea beans were treated with powders at concentrations of 5.0 grams and different doses of 0.25, 0.50, 0.75 and 1.0% (mass/mass of powder grains) and preferably tests and survival against c. maculatus. As regards the Lemongrass repellency, Boldo and Mint insects exhibited repellent properties, better specifying the insects did not have the same preference. The Maytenus, the bugs proved attractive/preferences. In referring to the survival every species have caused mortality at any given period of time.
53

Implications of past and future vegetation change for the lizard fauna of Motunau Island

Bannock, C. A. January 1998 (has links)
Abundance, distribution and habitat preferences of the lizard species present on Motunau Island, off the Canterbury coast of New Zealand, were investigated. The aim of the study was to investigate the extent to which recent vegetation change on Motunau Island has effected the lizard community and what implications this has for the future management of the Island. Three species of lizard occur on Motunau Island; the common gecko (Hoplodactylus maculatus), common skink (Oligosoma nigriplantare polychroma) and spotted skink (O. lineoocellatum). Rabbits (Oryctolagus cuniculus) were present on the island from 1862 until their eradication in 1962. Since then, vegetation on the island has changed from being tussock-dominated to being dominated by exotic weeds. Data from lizard pitfall trap surveys carried out in 1967-75 by Tony Whitaker of the Department of Scientific and Industrial Research (DSIR) were compared with new pitfall trapping data to determine if changes in the lizard population had occurred in response to these vegetation changes. The abundance of O. n. polychroma and H. maculatus does not appear to change significantly. The distribution of these two species were significantly correlated but neither showed any preference for a particular type. The abundance of O. lineoocellatum was significantly greater in 1996/97 than in the earlier DSlR surveys. This could be a result of the vegetation becoming more open and more structurally complex since the early surveys. This would offer greater opportunities for O. lineoocellatum (which is strongly heliothermic) to thermoregulate and forage. O. lineoocellatum showed no consistent significant preference towards any habitat type, although they tended to be found more in 'margin' habitat. Research into pitfall trapping and the way lizard behaviour may influence pitfall trapping data needs to be undertaken as there is a possible trap bias in this study. Management of Motunau Island needs to ensure that a structurally complex environment is maintained to ensure high numbers of all three lizard species can continue to coexist.

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