The sanctuary, in the Nandyal district of Andhra Pradesh, is close to the state's border with Karnataka and is 40 km from the district headquarters of Nandyal, 172km from Kadapa, and 152km from Raichur. Covering an area of 6.14 km2, it was established in 1988 to protect the great Indian bustard and the lesser florican and remains the only habitat in Andhra Pradesh for the bustard which is a critically endangered species.[2][3] The sanctuary is mostly an undulating plain with hot, dry climatic conditions and erratic and uneven rainfall. It has an average elevation of 290 metres and receives about 450 mm of rainfall annually.[4]
An increase in the blackbuck population at the sanctuary has been postulated as one of the reasons for the fall in numbers of the bustard and the florican there. Their feeding on the grasses has in turn led to a fall in the numbers of grasshoppers and locusts that constitute an important source of food for the two bird species besides also reducing the nesting area available to these ground nesting birds.[7]
Threats
Established as an ideal site for the protection of the bustard in the 1980s, conservation efforts at Rollapadu have suffered severe setbacks in recent years with the bustard population falling in recent years. The sanctuary houses nearly 800 blackbucks which often raid the farmlands beyond the sanctuary's borders and this has led to public anger against the sanctuary. Grazing of cattle within the sanctuary's precincts has also affected the breeding of the bustards.[4][8] Changes in the ecosystem due to the linking of the Alganur tank with the Telugu Ganga Canal and the consequent rise in ground water levels in this semi-arid region have led to changes in flora as well as in the nature of agriculture practiced around the sanctuary's periphery. Harriers have been found dead presumably due to the effect of biomagnification. Foxes, the Lesser florican and Greater short-toed larks have not been spotted at the sanctuary in recent years.[7]