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dc.contributor.authorPeacock, DS
dc.date.accessioned2007-05-11T09:25:46Z
dc.date.available2007-05-11T09:25:46Z
dc.date.created2006en
dc.date.issued2007-05-11T09:25:46Z
dc.identifier.urihttp://hdl.handle.net/123456789/268
dc.descriptionThe dataset provides the number of individuals per species observed at each of 120 point count sites. All sites were visited 4 times, and the numbers given here are the summed values across all 4 these replicates. The 120 sites were selected to represent a gradient of urbanization; however, certain sites were omitted from the classification due to uncharacteristic land-cover values. These are indicated by "NA". The remainder (39 sites) are classed as either Urban (U), Suburban (SU) or Semi-Natural (SN).en
dc.description.abstractUrbanisation and invasive alien species constitute two of the most severe threats to biodiversity conservation in the 21st century. It is particularly concerning that these two threats often occur sympatrically and work synergistically in that continued alteration and deterioration of pristine ecosystems by the human urban sprawl changes intact biological communities’ species richness, composition and guild structuring, thereby allowing a numerically small ensemble of ecological generalists to prosper at the expense of richer and more diverse indigenous communities. An excellent South African example of such a prosperous generalist is the invasive alien Common Myna Acridotheres tristis. Centred on Pretoria, Gauteng, this study used point count surveys in combination with land-cover classification to conduct a community-level analysis of avian richness and diversity across a gradient of urbanisation. In particular, I identify and quantify bird communities associated with three levels of urbanisation (‘Urban’, ‘Suburban’ and ‘Semi-Natural’) and investigate land-cover variables that determine the distribution, numerical abundance and population density of the Common Myna in relation to sympatric indigenous species. Generally, species richness and ‘endemicity’ increased with decreasing urbanisation levels, whereas the number of individual birds showed the opposite trend. Common Mynas reach their highest densities in ‘Urban’ areas (3.25 birds/ha), compared to ‘Suburban’ (2.43 birds/ha) and ‘Semi-Natural’ (0.59 birds/ha). Mynas prefer areas dominated by urban greenery e.g. sports fields, parks and lawns, showing a strong positive correlation with this land-cover variable. In contrast, correlations for ‘Urban’ and ‘Suburban’-dominated areas were nearly neutral, while selection for ‘Semi-Natural’ sites was moderately negative. Despite claims that mynas compete with, and potentially displace indigenous species, evidence for this is lacking. The results of this study suggest that mynas are strongly attracted to areas severely altered by urbanisation where they potentially compete with a relatively species-poor avian community, many of which are also alien.en
dc.description.statementofresponsibilityVhengani, Lufuno
dc.format.extent572416 bytes
dc.format.extent16323 bytes
dc.format.extent166473 bytes
dc.format.mimetypeapplication/vnd.ms-excel
dc.format.mimetypeapplication/pdf
dc.format.mimetypeapplication/pdf
dc.languageEnglishen
dc.language.isoen_US
dc.rightscopyrighten
dc.subjectEntomologyen
dc.titleThe ecological dynamics of the invasive alien Common Myna Acridotheres tristis, L (Aves: Sturnidae) in South Africaen
dc.mdidentification.purposeTo calculate species-specific and community-level avian densities and habitat preferences along a gradient of urbanization.en
dc.mdidentification.organizationnameCentre of Excellence for Invasion Biologyen
dc.mdidentification.deliverypointFaculty of Science, Natural Sciences Building, Private Bag X1, University of Stellenbosch, Matielanden
dc.mdidentification.postalcode7602en
dc.mdidentification.phone0218083607en
dc.mdidentification.electronicmailaddressvhengani@sun.ac.zaen
dc.mddataidentification.languageEnglishen
dc.mdusage.specificusageThe dataset gives the number of individuals per species observed for each of 120 sites, summed across 4 replicates.en
dc.mdusage.userdeterminedlimitationsData gathered during (austral) winter - summer migrants not surveyed.en
dc.mdusage.usagedatetime2006
dc.mdconstraints.uselimitationGooden
dc.mdlegalconstraints.accessconstraintscopyrighten
dc.mdlegalconstraints.otherconstraintsSubject to CIB data rulesen
dc.lilineage.statementOriginal Dataset compiled by DS Peacocken
dc.dqcompletenessomission.valueunitPercentageen
dc.dqcompletenessomission.valueattributedata100en
dc.mdmaintenanceinformation.maintenanceandupdatefrequencyUnknownen
dc.mdfeaturecataloguedescription.cataloguedate2007-05-11
dc.mddistributor.distributorcontactN/Aen
dc.mdformat.nameExcel and PDFen
dc.mdformat.versionN/Aen
dc.exgeographicboundingbox.westboundlongitude28.18°en
dc.exgeographicboundingbox.eastboundlongitude28.37°en
dc.exgeographicboundingbox.northboundlattitude25.72°en
dc.exgeographicboundingbox.southboundlattitude25.90°en
dc.exverticalextent.minimumvalue1200en
dc.exverticalextent.maximumvalue1542en
dc.exverticalextent.unitofmeasuremetersen
dc.cibprojectNAen


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