A comparative study of the diet of the Indian Eagle Owl Bubo bengalensis (Franklin, 1831) from two distinct habitats in the Tamil Nadu - Puducherry area, southern India

• Main Authors: M. Eric Ramanujam, Tushita Singh
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wildlife Information Liaison Development Society 2017
• Subjects: intraguild aggression/predation; linnaean and wallacean shortfalls; non-volant small mammals; murid rodents; prey spectrum; Ecology; QH540-549.5; General. Including nature conservation; geographical distribution; QH1-199.5; Indian; Rattus rattus
• Online Access: https://doi.org/10.11609/jott.2438.9.3.9892-9902; https://doaj.org/article/520b34cb47674e4088e6281241cdbcbd

A total of 166 prey items were identified from pellets, pellet remains and prey remains – 84 from Arunachala Hill and 82 from Pondicherry University campus. The total biomass encountered from pellet and prey remains was 22,620.17g – 11,240.59g from Arunachala and 11,379.58g from Pondicherry University. Out of the 166 prey items 102 were non-volant small mammals accounting for a biomass of 13,973.90g – 5,616.83g (49.94%) from Arunachala and 8,357.07g (73.42%) from Pondicherry University. Even among these murid rodents dominated – 44.99% in Arunachala and 70.13% in Pondy University. Milvus migrans were predated upon by Bubo bengalensis and 10 partly eaten carcasses were recovered – hence they could not be assigned a category as the quantity consumed could not be determined. It is a well known fact that Eagle Owls are intolerant to other avian predators, and territorial behaviour and intraguild aggression / predation could be responsible for this phenomenon. 3 other partly consumed remains of birds were also encountered and these too could not be assigned a category for the same reason that the quantity ingested could not be determined. Anurans occurred for a combined biomass of 12.87% in both areas. The rest, viz. Coleoptera, Orthoptera and Paratelphusa sp. accounted for a paltry biomass of 0.51%. The difference between murid rodents occurring in the two habitats was illuminating. In Arunachala the constant food of the owls were the field rodents Millardia meltada (15.47%), Bandicota bengalensis (8.74%) and Tatera indica (11.65%), and a single Bandicota indica (6.07%) which is a species found around rural habitations. The first two species were conspicuous by their absence in Pondicherry University and the Tatera indica was encountered in very small quantities (3.70%). Uniquely enough, the terrestrial and fossorial forms of urban rodents formed the basic food of Bubo bengalensis in Pondicherry University – Rattus rattus (20.64%) and Bandicota indica (43.94%). Both these species are human commensals and occur in ...