Food composition of Indian Eagle Owl Bubo bengalensis Franklin (Aves: Strigiformes: Strigidae) from Tiruchirappalli District, Tamil Nadu, India

Abstract

The diet of the Indian Eagle Owl was studied from April to September 2017 in Tiruchirapalli District, Tamil Nadu, India. Analysis of 1082 regurgitated pellets yielded 2077 prey items; the mean prey items/ pellet was 1.91. The diet constituted 65.1% of rodent prey and the remaining 34.83% of other groups of both vertebrate and invertebrate animals. The mean percentage of prey composition was 31.15% Millardia meltada Soft-furred Field Rat, 12.95% Bandicota bengalensis Lesser Bandicoot Rat, 10.25% Mus booduga Indian Field Mouse, and 10.24% of other rodent species. Of the 34.83% of non-rodent prey, the owls ingested insects (Rhinoceros beetles, 9.58%), Arachnida (Solifugae or Sun spider, Galeodes sp., 9.58%), reptiles (Calotes sp., 3.7%), amphibians (3.56%), shrews (Suncus murinus, 2.84%), and others (5.57%). The Indian Eagle Owls consumed more than one prey per day and chiefly foraged in agricultural crop fields and consumed both small mammals and insects of agricultural importance under crop ecosystems.

Analysis of Toxic Heavy Metals in the Pellets of Owls: A Novel Approach for the Evaluation of Environmental Pollutants

“…The metal concentration of Mn in the pellets of the owl species studied here coincided well with earlier research works. Mn is a vital element for growth and development, but indiscriminate use and continued exposure could pose negative effects on avian species [5]. The acute toxic level of Mn (21.3-469.5 mg/kg) creates muscular and hypodermal tissues, interrupting avifauna's immune cells [26,27].…”

“…In total, 30 pellets were sampled fortnightly using the roosting and breeding sites of the Barn Owl, Spotted Owlet, Indian Eagle Owl, Brown Fish Owl, and Mottled Wood Owl between December 2019 and November 2020. The sampling sites were recognized by secondary signs such as regurgitated food items, milky white stools, prey leftovers, and feathers [5,12,13]. Regurgitated pellets were wrapped in aluminium foil and were bagged in separate zip-locked covers, and the labelled covers were transported to the workroom for further investigation.…”

“…Owls are the best night hunters, and are involved in the food chain and web [3]. They are dietary generalists who mostly prefer to prey on rodents [4,5].…”