The Population Ecology of the Rodents of the Rajasthan Desert, India

Abstract

Rodents constitute one of the largest mammalian groups in the Rajasthan desert, India, both in total number and in the number of species represented. They exhibit a great plasticity in respect of their choice of a wide spectrum of desert habitats and their impact on the desert ecosystems is all too prominent. The rodents’ role in the intensification of desertic conditions may be comprehended from the fact that a single species, viz. Meriones hurrianae***, is able to excavate about 61,400 kg of stabilised soil per km2 per day during summer and deposit it outside its burrow openings in a loose formation. This dug-up soil is easily blown away by the strong desert winds. The rodents, thus, are a prime biotic factor for soil erosion. Their impact on the desert vegetation as a result of their gnawing, debarking, cutting and feeding propensities is easily discernible throughout the tract. In the desert region, orchards, crop fields and rangelands cannot attain their optimum productivity without a rodent control programme. The rodents are, therefore, regarded to be the most potent enemies of man in the desert in his endeavours for maximizing output from this inhospitable terrain. In view of the considerable economic importance of a large number of desert vertebrates, and especially rodents, a study was initiated in the Rajasthan desert in 1953 with financial assistance of the Unesco***. Later on, in 1959, the Central Arid Zone Research Institute at Jodhpur provided a small cell of workers to study the ecology of the rodents and to devise means of their control in the Rajasthan desert. A brief review of our work on the population structure of rodents, their ecological distribution, home ranges, food, predators and reproduction aspects has been presented here. The control aspects of our work have been deliberately left out of this review.