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Distribución y estatus de Tyto alba (Scopoli, 1769) en Tenerife, islas Canarias (Aves, Tytonidae)

Authors:
  • Canary Islands' Ornithology and Natural History Group (GOHNIC)

Abstract

Data are presented referring to the distributíon and status of the Barn Owl (Tyto alba) in Tenerife. The species has been detected in 74 of the 114 grid squares (5 x 5 kms.) prospected. Most of the contacts (70.1%, n = 174) were registered between 0-300 m. a.s.l. with a significant proportion being concentrated between 51-100 m. The possible reasons for the observed tendency to occupy the lower zones in conjunction with the irregular distribution pattern in the Anaga an Teno Massifs are discussed. The maximun altitude at which breeding has been recorded is 1,080 m., although birds have been registered at 1,200 m., and one cannot rule out their presence at higher altitudes. The population has been estimated to comprise a minimum of 161 pairs, but the true figure could well be in the order of 250.
... Information on the bird's status and trends is scarce, with the exception of the islands of Tenerife and La Gomera, where censuses have been carried out. A population of about 250 pairs is estimated for Tenerife (Siverio 1997), whilst only about 15 pairs have been proposed for La Gomera ). The first evidence of nesting was obtained for Gran Canaria in 1987 (Trujillo 1989). ...
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