Abstract. Management and conservation strategies for endangered species require information on their temporal and spatial behavioral and habitat use relationships. We evaluated activity patterns and resource selection of black bears in northwestern Mexico. We surveyed 29 localities with 1450 camera traps stations from 2009 to 2013 in the states of Sonora and Chihuahua, Mexico. In each locality, we calculated the proportion of diurnal, nocturnal, and crepuscular activity through a kernel density estimator based on the time of independent photographic events, and we built a beta regression between diurnal density and annual temperature, seasonal rainfall (SR), human density, road density, daylight hours, season, and management type. To evaluate resource selection, we built a binomial logistic regression model incorporating Normalized Difference Vegetation Index (NDVI), mean and coefficient of variation of annual temperature, human population density (PD), terrain roughness, and season. Black bear activity was primarily diurnal with a bimodal tendency around sunrise and sunset. Diurnal activity (between sunrise and sunset) was positively influenced by daylight hours, SR, and private reserves and negatively influenced by anthropogenic factors. Resource selection was positively influenced by the coefficient of variation in temperature and NDVI and negatively associated with average annual temperature, PD, and terrain roughness. Activity patterns and resource use were similar to other regions in North America. However, temperature was one of the main factors influencing black bear activity and resource selection in our study areas and should be considered when developing management plans given projected increases in temperature expected under climate change scenarios. We present the first work of its kind for northwestern Mexico and considered it as an important component in future survey and management protocols for the species in the southern portion of its distribution.

White-tailed deer are an ecologically and economically important species in Mexico, with limited information on population status throughout the country. The aim of this study was to estimate the abundance and density of white-tailed deer using an alternative method with camera traps in northeastern Sonora, Mexico. We placed 31camera traps with attractants along trails and major wildlife crossings. The photographic records obtained were identified at the individual level through a comparative analysis of opinions. We built a capture-recapture history for each individual, thus creating a database of presence -absence. The abundance was estimated using the program MARK. We calculated an effective sampling area based on the average home range of the species of 55.10 km 2 . The abundance was divided by the effective sampling area to estimate density. Abundance for white-tailed deer was 130 ± 26.51 individuals for a density of 2.36 ± 0.48 ind/km 2 .These results are comparable to previous studies using fecal group surveys and aerial count surveys. Thus indicating a healthy local white-tailed deer population; however it is necessary to extend the camera trap monitoring to additional areas with different types of management. Finally, we consider the use of camera traps and the method developed for this study, to be valid and valuable alternatives to estimate white-tailed deer population fast and efficiently, particularly in such locations where information is lacking, additionally this methodology could be applied to the other mammalian species that potentially could be photographed in a given session.

No abstract

El conocimiento sobre la distribución de la mayoría de las especies es incompleto y fragmentado, debido a la falta de registros en colecciones científicas u observaciones fidedignas, como esel caso del oso negro americano (Ursus americanus) particularmente al NO de México. El objetivo fue recuperar datos históricos y actuales de ocurrencia de la especie en la ecorregión de la Sierra Madre Occidental y las Islas del Cielo. Se recopilaron registros de diversas colecciones y museos (nacionales y extranjeras), estudios históricos y actuales (artículos científicos, informes, tesis, reportes sin publicar) e informantes clave. Se obtuvieron 88 registros (10 ♂, 10 ♀, 68 sexo indeterminado) en un periodo de 120 años (1890-2010). De colecciones científicas se obtuvieron 54 registros, 29 fueron obtenidos de la literatura y cinco de informantes confiables. La mayoría de los registros se ubicaron espacialmente dentro de cinco Áreas Naturales Protegidas y seis Regiones Terrestres Prioritarias. Los Estados de Chihuahua y Sonora contaron con más registros, colectados en el período de 2001-2010; para los periodosde 1921-1930 y 1941-1950 no se obtuvieron registros. El bajo número de registros obtenidos es reflejo de la falta de estudios a lo largo de la distribución de la especie en México, y la carencia de reportes formales sobre avistamientos, capturas o muertes de los animales a nivel local. El presente trabajo contribuye sustancialmente a identificar y examinar los vacios geográficos de información respecto a la especie, funcionando como línea base para la toma de decisiones, principalmente para aplicar técnicas y métodos que ayuden a seleccionar sitios prioritarios para su conservación. Es imperante reconocer la necesidad de implementar estrategias de manejo y conservación de la especie, a fin de poder mantenerla a largo plazo en nuestro país.

Abstract:We present the first systematic checklist of medium and large terrestrial mammals on four mountain ranges known as Sky Islands, in northeastern Sonora, Mexico. We used camera traps for recording mammals, with which we documented 25 wild species. Two of the native species are in the IUCN Red List and four are threatened at the national level. We did not document seven wild species with potential distribution at study sites, probably due to limited availability of habitat and/ or local extirpation of species. The importance of this work is that we generated an inventory of medium and large mammals in an area considered poorly studied and highly diverse.