Determinación de la dieta del tecolote moteado mexicano (Strix occidentalis lucida) en Sierra Fría, Aguascalientes

Abstract

DURING 1996 AND 1997, 35 REGURGITATED PELLETS OF THE MEXICAN SPOTTED OWL (STRIX OCCIDENTALIS LUCIDA NELSON 1903) WERE COLLECTED IN THREE LOCALITIES IN SIERRA FRIA, AGUASCALIENTES. THE DIET WAS DETERMINATED ON BASIS OF UNDIGESTED PREY RE- MAINS. ONE HUNDRED AND FORTY FIVE PREY INDIVIDUALS WERE IDENTIFIED; NINE GENERA OF SMALL MAMMALS, TWO FAMILIES OF BIRDS AND INSECTS OF THE ORDERS ORTHOPTERA, HOMOPTERA, COLEOPTERA AND LEPIDOPTERA. VERTEBRATES CONSTITUTED 62% OF THE PREY TAKEN AND CONTRIBUTED WITH 99% OF THE TOTAL BIOMASS INGESTED. IN THIS GROUP, MICE (PEROMYSCUS SP. AND REITHRODONTOMYS SP.) WERE THE MOST FREQUENT PREY, WHEREAS WOOD RATS (NEOTOMA SP.), RABBITS (SYLVILAGUS SP.) AND THE COTTON RAT (SIGMODON HISPIDUS) CONTRIBUTED WITH 68% OF THE TOTAL BIOMASS. ALTHOUGH THE DIET OF THIS OWL INCLUDES A GREAT VARIETY OF PREY, THE MAIN FOOD ITEMS ARE SMALL MAMMALS.