Abstract

FUENTES, Lilian; SEQUERA, Isabel; POLEO, Carmen  and  DIAZ, Lisbeth. Diet composition of Tyto alba in habitats of Calabozo, Venezuela. Investig. Agrar. [online]. 2015, vol.17, n.1, pp.46-53. ISSN 2305-0683.  https://doi.org/10.18004/investig.agrar.2015.junio.46-53.

In order to determine the diet of the Barn Owl (Tyto alba Scopoli, 1769), 592 pellets were collected from January to December 2010 at one month interval, at the National Institute of Agricultural research’s experimental center, in Calabozo, Guárico State, Venezuela. In addition, precipitation records during the dry and rainy seasons were obtained at the field research site. In the laboratory, each pellet was measured to determine size and weight. Then, each pellet was dry-processed to estimate total amount of consumed prey, species in some groups, the average number of prays per pellet and the relationship between the number of consumed preys and pellet´s weight and between number of preys and rainfall. Mean weight, length and width of pellets were: 3.6 g ± 1.5, 2.7 cm ± 0.6 and 1.8 cm ± 0.4, respectively. The owl´s diet included 847 preys, comprised by rodents (Zygodontomys brevicauda, Sigmodon alstoni, Holochilus sciureus and Oligoryomys sp.) (99.30 %), birds (Cuculidae and Passeriformes) (0.23 %) and bats (Mollosus sp.) (0.47 %). The average number of individuals per pellet was 1.5 ± 0.4. Pellets weight was directly related to number of prey (r = 0.4377; P = 0.000). Number of consumed prey and rainfall were inversely related (r = -0.7304; P = 0.007), however, diet composition was not affected by either rainy or dry season. T. alba showed to be a potential hunter of rodent and it can be useful as a biological agent against invasive rodent species in rice fields of Venezuela.

Keywords : Holochilus sciureus; Mollosus; Oligoryzomys; Sigmodon alstoni; Zygodontomys brevicauda.

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