Academic literature on the topic 'Urban entomology'

The diversity and community composition of birds and seven insect taxa: butterflies and skippers (Lepidoptera); Carabidae (Coleoptera); Dolichopodidae, Syrphidae, Sphaeroceridae, Chloropidae (Diptera); Apoidea (Hymenoptera) were studied in old field habitats surrounded by different intensities of urbanization in the Montreal region. A total of 386 breeding birds of 42 species as well as 2255 migrating birds of 31 species were surveyed. More than 7000 insect specimens of 264 species were identified. Results indicate that, in terms of studied taxa, old field biodiversity remains fairly constant despite different surrounding land use. The exceptions were that butterfly and skipper species richness and number of Syrphidae specimens collected were both higher in suburban than periurban sites, and breeding birds were more abundant in rural areas compared to suburban ones. Breeding bird communities in suburban areas were most similar to one another. Despite these findings, the overarching pattern was that the diversity and community composition of birds and insects did not differ between old fields in suburban, periurban, or rural areas. Chloropidae was the only taxon influenced by surrounding land use, particularly by amounts of residential, industrial/commercial/transportation areas, and green space. Because of the differences in responses, none of the taxa were reliable bioindicators of diversity patterns in all the other taxa, however, some significant correlations between individual taxa were established.<br>Cette étude visait à comprendre la diversité et la composition des communautés d'oiseaux et d'insectes présentes dans des champs abandonnés par rapport à l'intensité d'urbanisation des terres adjacentes dans la région de Montréal. Les sept taxons d'insectes choisis étaient: les papillons et les hespéries (Lepidoptera); Carabidae (Coleoptera); Dolichopodidae, Syrphidae, Sphaeroceridae, Chloropidae (Diptera); Apoidea (Hymenoptera). Au total, 386 oiseaux nicheurs représentant 42 espèces, ainsi que 2255 oiseaux migrateurs représentant 31 espèces ont été répertoriés. Plus de 7000 spécimens d'insectes comprenant 264 espèces ont été identifiés. Les résultats indiquent que la diversité des champs abandonnés reste stable, malgré des différences dans l'urbanisation des terres adjacentes, du moins dans les groupes étudiés. Toutefois, il y avait quelques exceptions : la diversité des papillons et des hespéries ainsi que l'abondance des syrphes étaient plus élevées dans les sites suburbains comparé aux sites periurbains; de plus, les oiseaux nicheurs étaient plus abondants dans les sites ruraux que les sites suburbains. Les assemblages d'oiseaux nicheurs dans les sites suburbains démontraient le plus grand degré de similitude les uns par rapport aux autres. Malgré ces résultats, le patron global indique que la diversité et les assemblages d'oiseaux et d'insectes dans les champs abandonnés diffèrent peu malgré des alentours suburbains, périurbains ou ruraux. Chloropidae serait le seul taxon influencé par l'urbanisation des terrains adjacents, particulièrement par la quantité de terrains résidentiels et industriels et d'espaces verts. Étant donné ces variations, aucun des taxons choisis n'a pu être utile en tant qu'espèce indicatrice des patrons de diversité des autres taxons; cependant, quelques corrélations significatives ont été établies entre certains taxons.

Bases para a implementação de um programa de manejo da resistência de Blattella germanica (L.) a inseticidas foram coletadas no presente trabalho. Técnicas de bioensaio de aplicação tópica e de contato tarsal foram comparadas inicialmente para a detecção da resistência a deltametrina e clorpirifós. O bioensaio de aplicação tópica possibilitou uma melhor discriminação entre a linhagem suscetível e as populações de campo de B. germanica testadas. Resultados do monitoramento da suscetibilidade de B. germanica a inseticidas evidenciaram a presença de variabilidade genética que confere resistência a deltametrina, clorpirifós e fipronil em populações coletadas em alguns estabelecimentos comerciais dos Estados de São Paulo e Rio de Janeiro. As razões de resistência encontradas para deltametrina e clorpirifós foram de aproximadamente 43 e 6 vezes, respectivamente. A resistência de B. germanica a deltametrina foi instável, ou seja, houve uma redução significativa na freqüência de resistência na ausência de pressão de seleção. Estudos de relações de resistência cruzada revelaram uma baixa intensidade de resistência cruzada (aproximadamente 2 vezes) entre fipronil e os inseticidas deltametrina e clorpirifós. E por último, a mistura de deltametrina e clorpirifós foi avaliada para o controle de linhagens de B. germanica resistentes a deltametrina. A mistura proporcionou um melhor controle da linhagem suscetível do que os produtos utilizados isoladamente. No entanto, a discriminação entre as linhagens suscetível e resistente a deltametrina foi evidente com a mistura nas doses recomendadas comercialmente, o que inviabilizaria o emprego desta estratégia no manejo da resistência de B. germanica a deltametrina.<br>Bases for implementing a resistance management program of Blattella germanica (L.) to insecticides were collected in this study. Initially, we compared the topical and residual tarsal-contact bioassays for detecting resistance to deltamethrin and chlorpyrifos. The topical bioassay gave better discrimination between susceptible and field-collected populations of B. germanica. Results from a survey of the susceptibility of B. germanica to insecticides revealed the presence of genetic variability that confers resistance to deltamethrin, chlorpyrifos and fipronil in field-collected populations of B. germanica from the States of São Paulo and Rio de Janeiro. The resistance ratios to deltamethrin and chlorpyrifos were approximately 43 and 6-fold, respectively. The resistance of B. germanica to deltamethrin was unstable; that is, a significant reduction in the frequency of resistance was detected under absence of selection pressure. Studies on cross-resistance relationships showed a low intensity of cross-resistance (approximately 2-fold) between fipronil and the insecticides deltamethrin and chlorpyrifos. And finally, the viabilility of the use of deltamethrin and chlorpyrifos mixture was evaluated for controlling deltamethrin-resistant strains of B. germanica. The use of mixtures gave better control of the susceptible strain than the use of the products by itself. However, the discrimination between susceptible and resistant strains was clear with the use of mixtures at recommended rates, which impairs the use of this strategy for managing B. germanica resistance to deltamethrin.

<p>Bees are essential for crop pollination services; however, the ecosystem services they provide by pollinating native plants are crucial for maintaining biodiversity in natural systems. This study analyzed bee community changes within, on the edge, and outside of forest fragments. Phenological variation over two seasons and modeling to predict bee abundance associated with forest characteristics was performed. Finally the genetic diversity of two species of Bombus was analyzed. Bowl traps and aerial sweep netting in and near forest patches were used to sample bee communities in northern Delaware between March and August, 2013 and 2014. Bee phenology stayed consistent between field seasons, but fewer bees were collected in 2014 compared to 2013. Abundance modeling (R: unmarked) predicted that bee abundance was negatively impacted primarily by agriculture surrounding the forest patch. Analyses using microsatellites revealed that B. impatiens lacked overt population genetic structure while B. bimaculatus showed two genetically distinct populations. Pesticide analysis revealed 17 pesticides observed on adult bees from seven urban and suburban forest patches. Further studies investigating natural bee fluctuations in response to multiple field seasons, floral diversity, and chronic pesticide exposure are crucial in order to assess native pollinator health.

Blood fed Culex quinquefasciatus were collected from residential and wetland sites in Tucson, Arizona for three years using CDC gravid traps. An ELISA distinguishing human, bird, dog, cat, and rabbit blood meals was used. In residential areas, approximately 47% of all identified blood meals were from humans, with fewer blood meals from bird, dog, cat, and rabbit. At Sweetwater Wetland, humans were also the most common host, with 11 (41%) identified blood meals. Birds were the hosts of 19% blood meals. Ten (seven residential, three wetland) mosquitoes were identified to have blood from both bird and human hosts. Since the transmission of West Nile Virus to humans is dependent on mosquitoes feeding both on birds and humans, this finding is particularly relevant. These data only describe the feeding choices of the mosquitoes collected from a limited number of sites in Tucson, and therefore, may not reflect feeding preferences more generally.

Thesis (MSc (Conservation Ecology and Entomology))--University of Stellenbosc, 2005.<br>Biodiversity is under enormous pressure from an increasing human population. Urbanisation, agriculture, and mining are just some of the factors responsible for the continuous degradation of the natural environment. Of these, urbanisation is one of the leading factors of diversity loss. To address this problem, it is necessary to understand the relationship between biodiversity and urban areas, as well as the relationship between society and biodiversity. This study focuses on these relationships and suggest ways in which urban biodiversity can be maximised without compromising on development. In order to create an urban environment that successfully supports maximised biodiversity, new methods and ideas must be developed to promote the protection of urban ecosystems. The Cape Floristic Region in South Africa is a good example of an area that requires immediate action in order to prevent enormous losses in biodiversity. Data have shown drastic decreases in natural vegetation cover in this area, and with its close to 9000 species, of which approximately 60% occurs nowhere else in the world. This state of affairs should be regarded as a serious crisis. This study consists of three main parts, the first being a literature review on the current relationships between the urban environment, society, and biodiversity. The second and third parts report on two empirical investigations on the campus of the Faculty of Health Sciences at the University of Stellenbosch in the City of Cape Town. The first of these investigates the possibility of using spirituality connected to nature as a promotional tool for conservation through rehabilitation or restoration of damaged urban vegetation habitats. For this purpose students’ and staff members’ opinions of the urban nature at the campus were tested. In the second investigation the options of restoring biodiversity to the campus was considered by exploring the best options available for rehabilitation while taking the current biodiversity status on and around the premises into account. This was carried out through three smaller projects that included the physical reintroduction of plant species, vegetation analysis, and bird identification and attraction. The response of employees and students at the Faculty of Health Sciences was found to be in favour of restoring vegetation and animal life to the campus. This is supported by a belief that their attitude towards their work would improve with improved natural surroundings. Initial rehabilitation attempts highlighted the complexity of rehabilitation practices by bringing forward challenges and problems experienced with the reintroduction of plant species. Despite these problems, increased plant diversity in experimental areas showed the possibility of successfully completing the project. Biodiversity analysis showed that methods of controlling vegetation used by the university are doing more harm than good, as it results in indigenous vegetation being displaced by exotic vegetation. This study introduces a number of questions regarding the relationship between urbanisation and biodiversity and to what extent the two should be linked. Hopefully it is a step in the direction towards marrying the urban and natural environment, and to create a sustainable urban environment where society no longer sees nature as something outside the city boundaries.