Diet Variations of the Barn Owl Tyto alba (Scopoli, 1769) in Madurai District, Tamil Nadu, Southern India

Diet variations of Barn Owl Tyto alba were determined by the analysis of 3,133 regurgitated pellets collected from ten different roost-sites in Madurai District from 2007 to 2009. The overall diet comprised 85.5% small mammals, 2.2% birds, 0.1% reptiles, 0.9% amphibians and 2.4% insects. Among small mammals, Suncus murinus and Rattus rattus were predominant: they comprised 37.2% and 23.0% of the 4,295 prey taken by Barn Owls. The number of prey items per pellet varied from one to 16 with an overall mean of 1.37 prey items/pellet. The percentage of small mammal in the pellets varied seasonally from 82.5% to 87.5%. Suncus murinus was taken in large numbers from post-monsoon (30.2%)to monsoon (51.1%). The occurrence of small mammals in the diet varied from 75.0% to 90.4% among the years. The consumption of Suncus murinus showed a decreasing trend from 2007 to 2009, whereas the Bandicoota bengalensis, Millardia meltada, Tatera indica, Mus spp. and chiropterans showed an increasing trend. Consumption of Rattus rattus,Tatera indica, Suncus murinus and amphibians were significantly differed among the years. Suncus murinus was chief prey in both rural and urban habitats. Bandicoota bengalensis (18.6%), Millardia meltada (7.8%), Tatera indica (1.8%), Musspp. (8.5%) and bats (4.2%) were found more frequently in the diet of owls in rural habitat, whereas, Rattus rattus contributed an important fraction of the prey (26.4%) in urban habitat. There were statistical differences in percent frequency of Bandicoota bengalensis, Millardia meltada, Rattus rattus, Tatera indica, amphibians and isopteran insects between the habitats.