Diet composition of introduced Barn Owls (Tyto alba javanica) in urban area in comparison with agriculture settings

Abstract

2This study investigated the diet of introduced barn owls (Tyto alba javanica, Gmelin) in the 3 urban area of the Main Campus of Universiti Sains Malaysia, Penang, Malaysia, based on 4 collected regurgitated pellets. We also compared the diet of introduced urban barn owls with 5 the diet of barn owls from two agricultural areas, i.e. oil palm plantations and rice fields. Pellet 6 analysis of barn owls introduced in the urban area showed that commensal Norway rats, Rattus 7 norvegicus, made up the highest proportion of the diet (65.37% prey biomass) while common 8 shrews, Suncus murinus were the second highest consumed prey (30.12% prey biomass). 9Common plantain squirrel, Callosciurus notatus, made up 4.45% of the diet while insects were 10 taken in a relatively small amount (0.046% prey biomass). Introduced barn owls showed a 11 preference for medium-sized prey, i.e. 40 to 120g (52.96% biomass and 38.71% total). In 12 agricultural areas, Rattus argentiventer predominated the diet of barn owls (98.24% prey 13 biomass) in rice fields while Malayan wood rats, Rattus tiomanicus, were the most consumed 14 prey in oil palm plantations (99.5% prey biomass). Food niche breadth value was highest for 15 barn owls introduced in an urban area with a value of 2.90, and 1.06 in rice fields and 1.22 in 16 oil palm plantations. Our analysis reiterates the prey preference of barn owls in various 17 landscapes for small mammals. Our results also indicate the suitability of utilizing barn owls 18 as a biological control not only in agricultural areas, but also as a biological control agent for 19 commensal rodent pests in urban areas. 20

Frequency of Occurrence and Ingested Biomass of Different Prey of the Barn Owl Tyto alba in an Island Ecosystem

“…All the species of small mammals recorded in Elba island were found in Barn Owl pellets, with the exception of the edible dormouse and the hedgehog, the first being known to only occur in densely wooded areas and is only rarely represented in the diet of this raptor bird in the island (less than in 1% pellets: [25]), the former presumably representing a challenging prey for T. alba due to its size and low palatability due to defensive spines. This confirmed that Barn Owls are not selective predators, and that they may shape their diet following the local availability of different prey species [48]. Shrews were about 9% more represented than in the previous work who collected pellets in the same area [30], who did not detect any pygmy white-toothed shrew remain in pellets.…”

“…A great plasticity in the diet of the Barn Owl has been proven in a high number of studies and reviews [13,27,46], but long-term studies assessing diet changes are still few [14][15][16]. Conversely, repeated studies conducted in the same study site may provide useful information on prey population trends and the local environmental status [13,46,48].…”

Nightlife in the city: drivers of the occurrence and vocal activity of a tropical owl

“…Among nocturnal birds, owls are particularly interesting given their role as top predators in most terrestrial habitats, with their presence often being related to ecosystem quality (Isaac et al 2013;Fröhlich and Ciach 2019). Actually, in some urban areas owls have been identified as important biological control agents of rodent pests (Saufi et al 2020).…”

“…Given the spatial heterogeneity of urban settings and their high density of potential preys for nocturnal raptors (e.g., rodents; Himsworth et al 2014), these areas can positively influence their abundance (Chace and Walsh 2006;Poppleton 2016). Although some owl species can be negatively affected by urbanization due to potential hazards such as vehicular and window collisions, built structures, artificial lighting, roads, diseases and poisoning (Poppleton 2016;Santiago-Alarcon and Delgado-VC 2017;Serieys et al 2019;Saufi et al 2020), other species have shown to thrive in urbanized areas (Gryz and Krauze-Gryz 2019). The ability of owls to deal with urban environments has been shown to depend on the availability of habitats for nesting and foraging to maintain its home range requirements (Galeotti 1990;Fischer et al 2015;Mori and Bertolino 2015;Poppleton 2016;Kettel et al 2018).…”

Ecological countermeasures for preventing zoonotic disease outbreaks: when ecological restoration is a human health imperative

“…Becker et al (2018), summarizing the findings of a collection of scientific papers that investigate the influence of anthropogenic resources subsidies on host‐pathogen dynamics in wildlife, conclude that public education and adaptive management can contribute to “win–win” scenarios for feeding wildlife that optimize benefits for conservation, wildlife disease management, and human health. Nest boxes have been used to increase and expand populations of native barn owls ( Tyto alba ) to control non‐native rodent populations in agricultural and urban environments (Saufi et al 2020). In Vermont, private landowners constructed more than 400 houses to attract native tree swallows ( Tachycineta bicolor ) for mosquito control.…”