![]() ![]() This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.ĭata Availability: All relevant data are deposited within the Dryad online repository (doi: 10.5061/dryad.m9p07).įunding: The first author was supported in the position of BirdLife South Africa Ingula Project Manager with funding by Eskom through The Ingula Partnership. Received: ApAccepted: AugPublished: October 5, 2016Ĭopyright: © 2016 Maphisa et al. Crowther, University of Sydney, AUSTRALIA We suggest that management of this grassland use combination of fire and grazing and leave some areas unburned to accommodates birds of various habitat needs.Ĭitation: Maphisa DH, Smit-Robinson H, Underhill LG, Altwegg R (2016) Drivers of Bird Species Richness within Moist High-Altitude Grasslands in Eastern South Africa. We conclude that frequent burning alone with relatively reduced grazing led to higher but less dense grass, which benefited some species and disadvantaged others. However, overall bird species richness was better positively correlated to grass height than grass cover or dead grass. On one hand birds that prefer moderate grazing were best explained by a null model. Changes in bird species richness were best explained by the model with grass height for combined species richness of grassland depended birds but also for birds that prefer heavy grazing when treated alone. Overall bird species richness increased over the three summer surveys but species richness of birds that prefer heavily grazed habitat showed little change over the three years. Bird species richness was highest in summer compared to other seasons and increased over time. Transects that were burned showed a larger decrease in vegetation cover compared to transects that were not burned. And finally we investigated which habitat vegetation attributes were correlated with species richness of a group of grassland depended bird species only. Secondly, we examined how total bird species richness varied across seasons and years. First we used generalised linear mixed models, to examine changes in vegetation grass height and cover and between burned and unburned habitats. To achieve these, we convert bird transect data to presence only data to investigate how bird species richness were related to key transect vegetation attributes under this new grassland management. We collected bird occurrence and vegetation data along random transects between 20 to monitor the impact of the new management, and to study the effect of the habitat changes on bird species richness. The new management seeks scientific advice on how to maintain avian species richness of the study area. Since the new management took over in 2005 the area has been mostly annually burned with relatively little grazing. An area that had been subject to intense grazing was bought by the national power utility that constructed a pumped storage scheme on part of the land and set aside the rest for bird conservation. A particularly good opportunity to study these issues arose at Ingula in the eastern South African high-altitude grasslands. ![]() There is therefore an urgent need to investigate environmental factors and habitat factors that affect bird species richness in order to optimise management of those areas set aside for conservation. ![]() Recently the area has become target for water storage schemes and renewable electricity energy projects. Conservation management of these areas conflicts with management for other uses, such as intensive livestock agriculture, which requires annual burning and leads to heavy grazing. ![]() Moist high-altitude grasslands in South Africa are renowned for high avifaunal diversity and are priority areas for conservation. ![]()
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