Ecology of the Mexican Red-Bellied Squirrel (Sciurus Aureogaster) in Michoacan, Mexico (Notes) (Report‪)‬

The Mexican red-bellied squirrel (Sciurus aureogaster) is native to Mexico and southwestern Guatemala (Thorington and Hoffmann, 2005). In Mexico, the species occurs on the Gulf and Pacific coastal plains from Tamaulipas to Tabasco on the east and from Colima to Chiapas on the west, inhabiting a wide variety of forests ranging from tropical scrub and broadleaf formations of the hot lowlands to cold and wet temperate cloud forests of oaks (Quercus) and conifers in the highlands (Musser, 1968). As with many species of tropical tree squirrels (Koprowski and Nandini, 2008), a dearth of information exists on their biology and ecology (McGuire and Brown, 1973; Brown and McGuire, 1975; Ceballos and Galindo, 1984; Ramos-Lara and Cervantes, 2007). Although the species is not listed in Mexico under any category of risk (Secretaria de Medio Ambiente y Recursos Naturales, 2002), Mexican red-bellied squirrels recently have been included in the Red List of Threatened Species (least concern) by the International Union for the Conservation of Nature (J. L. Koprowski et al., www.iucnredlist. org). There is a need for more information concerning the basic ecology of this species. During November 2000-May 2002, we collected information on feeding and nesting behavior, reproductive condition, and activity patterns of Mexican red-bellied squirrels during a study of nest-site selection (Ramos-Lara and Cervantes, 2007), in a small portion (100 ha) of the oak-pine (Quercus-Pinus) forest ca. 7.5 km S Patzcuaro, Michoacan, Mexico (19[degrees]27'29.1"N, 101[degrees]36'41.6'W; elevation 2,340 m). Dominant species of trees were Quercus candicans, Q. crassipes, Q. laurina, Q. obtusata, Pinus pseudostrobus, Clethra mexicana, Cornus disciflora, Styrax ramirezii, Symplocos prionophylla, and Ternstroemia pringlei. During 2001, mean monthly precipitation in the region was 3.83 mm ([+ or -] 8.45 SD, n = 6) for the dry season (November-April), and 160.95 mm ([+ or -] 108.54 SD, n = 6) for the wet season (May-October), with a mean annual temperature of 15.06[degrees]C ([+ or -] 2.53 SD, n = 12), according to information provided by Servicio Meteorologico Nacional. Each month, we traversed the same dirt roads and trails in search of leaf nests (Ramos-Lara and Cervantes, 2007), and opportunistically recorded information on the ecology and behavior of Mexican red-bellied squirrels. The absence of other species of tree squirrels in the study area facilitated identification and observation of squirrels. We randomly placed 10 nest boxes (Barkalow and Soots, 1965) in mature trees ca. 4 m above ground to obtain data on reproduction. During 30 April-2 May 2002, we collected six Mexican red-bellied squirrels (three adult males, two adult females, and one juvenile male) using a 12-guage shotgun; sex, age class, reproductive condition, and body mass were recorded. Squirrels were prepared as museum specimens and deposited in the Coleccion Nacional de Mamiferos of the Instituto de Biologia, Universidad Nacional Autonoma de Mexico, in Mexico City.