![]() ![]() In addition to heavy livestock grazing and other agricultural activities, this area is a target for energy development projects to meet growing human demand for electricity and water for consumption (Maphisa et al. Regionally, fire is an important conservation management tool used both on private and state lands to make habitats suitable for birds (Parr and Chown 2003). 1999) have examined abundance or densities of bird species in relation to habitat features that can be managed. As a result, a number of Important Bird and Biodiversity Areas (IBAs) have been proclaimed in the area (e.g. This area also coincides with high avifaunal species richness, diversity and endemism (Maphisa et al. In particular, South Africa’s moist grasslands harbor globally significant biodiversity, supply essential ecosystem services, support crop and livestock, forestry and settlement, yet are poorly conserved (O’Connor and Kuyler 2009). An assessment of conservation priorities in the Grassland Biome in southern Africa identified 36.7% of the biome as being important for biodiversity conservation (Egoh et al. In southern Africa, grasslands are also one of the most threatened biomes, with 23% under cultivation, 60% irreversibly transformed, 2% formally protected and most of the remaining natural areas used as rangeland for livestock (Fairbanks et al. Globally, the grassland biome and associated species are threatened and require management interventions to prevent further habitat loss and species extinction (With et al. We suggest that conservation managers of these grasslands combine fire and grazing as management tools to create suitable habitats for grassland birds in general. This study supports previous studies suggesting that grazing and fire are important tools for management to use in order to create a mosaic of grass height and cover that would support high densities of desired species. The regression splines show that the effect of these two habitat variables on density is well described by linear relationships for most species. ![]() Our results agree with previous studies that grass height combined with grass cover are the most important habitat features that managers should manipulate in order to increase the density of target species. The Cape Longclaw ( Macronyx capensis) and Zitting Cisticola ( Cisticola juncidis) preferred tall and dense grass. The Yellow-breasted Pipit ( Anthus chloris), African Pipit ( Anthus cinnamomeus) and Red-capped Lark ( Calandrella cinerea) preferred short and relatively dense grass, while the Wing-snapping Cisticola ( Cisticola ayresii) preferred grass of intermediate height and cover. The African Quailfinch ( Ortygospiza atricollis) and Common Quail ( Coturnix coturnix) preferred relatively short and open grass. Resultsįor most species, density is related to grass height and cover as expected. In addition, we used regression splines within these distance sampling models as a more flexible description of suitable ranges of grass height and cover for each species. We used hierarchical distance sampling methods to estimate density of birds relative to two main habitat variables, i.e., grass cover and height. We collected data on birds and habitat from the austral summers of 2006/2007, 011. We estimated the density of the eight most common grassland bird species encountered in our area to evaluate the effects of recent grassland management changes on the avifauna. ![]() We examine drivers of bird densities in a South African grassland area that has been managed for biodiversity conservation with reduced grazing pressure. Understanding how key grassland habitat attributes determine grassland bird densities is required to make appropriate conservation decisions. World-wide grassland birds are in decline due to habitat loss and degradation resulting from intensive agricultural practices. ![]()
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