The Grassland Birds of Rollapadu Wildlife Sanctuary, Andhra Pradesh, India, with Special Reference to the Impact of Grazing-Free Enclosures

Abstract

Grassland bird composition was studied in grazed (village grazing lands) and ungrazed grasslands (grassland enclosures of the Forest Department) at Rollapadu Wildlife Sanctuary from August 1992 to July 1994, using belt transect sampling. A total of 32 grassland dependent birds (21 resident, 4 winter migrant, and 7 seasonal migrant) were recorded in both the habitat types. Of these, 25 species were recorded in each of the two habitat types with 20 of them common to both. Although based on small sample size, our study showed that the species composition differed between grazed and ungrazed grasslands. Five species common in grazed grassland (Indian Courser Cursorius coromandelicus , Redwattled Lapwing Vanellus indicus , Red-winged Bush-Lark Mirafra erythroptera , Rufous-tailed Finch-Lark Ammomanes phoenicurus , and Plain Prinia Prinia inornata ) were not recorded in ungrazed grassland, while two species common in ungrazed grassland (Zitting Cisticola Cisticola juncidis and Black Drongo Edolius macrocercus ) were not recorded in grazed grassland. The abundance of certain bird species differed between the grazed and ungrazed grassland. Ungrazed grassland had higher numbers of Oriental Skylark Alauda gulgula , while the numbers of Sykes's Crested Lark Galerida deva , Ashy-crowned Sparrow-Lark Eremopterix grisea , and Yellow-wattled Lapwing Vanellus malabaricus were greater in grazed grassland. These differences could be due to the impact of livestock grazing, protection, the interaction of relative abundance of food resources and foraging strategy of birds, and/or other unknown factors. The study suggests that mosaics of grazed and ungrazed grasslands may result in an increase in grassland bird diversity. However, since the majority of Indian grasslands are grazed, we recommend the establishment of more grazing-free refuges encompassing different grassland types, to conserve bird species intolerant to grazing. There necessarily has also to be a landscape-level conservation strategy since the majority of India's grasslands have high human dependence, and thus, their conservation requires the support of local communities in the long run.