Comparison of geographic distribution models of white-tailed deer Odocoileus virginianus (Zimmermann, 1780) subspecies in Mexico: biological and management implications

THERYA, Abril, 2010 Vol.1(1): 41-68 DOI: 10.12933/therya-10-5 Comparison of geographic distribution models of white-tailed deer Odocoileus virginianus (Zimmermann, 1780) subspecies in Mexico: biological and management implications Salvador Mandujano1*, Christian A. Delfín-Alfonso2,3 and Sonia Gallina1 Abstract The white-tailed deer (Odocoileus virginianus) is the most widely distributed and studied ungulate in the American continent. This species is found throughout Mexico, except on the peninsula of Baja California and some areas of northern Chihuahua and Sonora. In this study we compared three geographic distribution models (Kellogg 1956; Hall 1981; Villarreal 1999) of white-tailed deer subspecies on a national scale, by state and by principal vegetation types. We found that neither the number of subspecies (13 or 14 of the 38 recognised subspecies), nor the geographical limits between subspecies coincided completely between models. Furthermore, for several subspecies, marked differences in distribution area were found depending on the distribution model used. Using multivariate analyses, we found that the 14 subspecies can be separated into three groups associated with different vegetation types: the northern subspecies associated with shrub land, the Pacific subspecies associated with temperate forest and tropical dry forest, and the south-eastern subspecies associated with tropical evergreen forest, cloud forest and tropical semi-deciduous forest. We suggest the classification of the 14 subspecies into three ecoregions. The data analyzed here is relevant to the management and conservation of the white-tailed deer subspecies and/or geographical variations in Mexico; it is also important to avoid the translocation of individuals into inappropriate areas with respect to their evolution and adaptation to different ecoregions. Key words: distribution, ecoregions, management, Mexico, subspecies, vegetation types. Red de Biología y Conservación de Vertebrados, Instituto de Ecología A. C., Carretera Antigua Coatepec No. 351, El Haya, Xalapa 91070, Ver., México. E-mail: , autor corresponsal 2 Red de Medio Ambiente y Sustentabilidad, Instituto de Ecología A. C., Carretera Antigua Coatepec No. 351, El Haya, Xalapa 91070, Ver., México. 3 Facultad de Ciencias Naturales, Universidad Autónoma de Querétaro, Av. de la Ciencia S/N Juriquilla, Delegación Santa Rosa Jáuregui, Santiago de Querétaro, C. P. 76230, Querétaro, México. 1 WHITE-TAILED DEER SUBSPECIES IN MEXICO El venado cola blanca (Odocoileus virginianus) es el ungulado con mayor área Resumen de distribución en el continente Americano. En México, se le encuentra en todo el territorio excepto la península de Baja California, algunas áreas del norte de Chihuahua y norte de Sonora. En este trabajo comparamos algunos modelos (Kellogg 1956; Hall 1981; Villarreal 1999) de distribución geográfica de las subespecies de venado cola blanca, a nivel del país, por entidad federativa y por tipos principales de vegetación. Se encontró que no coinciden totalmente ni en el número de subespecies (13 ó 14 de las 38 subespecies reconocidas), ni en los límites geográficos entre subespecies; además de que para algunas subespecies existen claras diferencias en las áreas de distribución dependiendo del modelo de distribución. Con base en análisis multivariados encontramos que las 14 subespecies pueden separarse en tres grupos asociados a diferentes tipos de vegetación: las subespecies norteñas asociadas al matorral xerófilo, las subespecies del Pacífico asociadas al bosque templado y bosques tropical seco, y las subespecies del sureste asociadas al bosque tropical perennifolio, bosque mesófilo y bosque tropical subcaducifolio. Sugerimos clasificar a las subespecies en tres ecoregiones. La información generada es relevante para el manejo y conservación de las subespecies y/o variaciones geográficas del venado cola blanca en el país, y evitar translocar individuos a sitios que no les corresponden de acuerdo a su evolución y adaptación a las diferentes ecoregiones. Palabras clave: distribución, ecoregiones, manejo, México, subespecies, tipos de vegetación. The white-tailed deer Odocoileus virginianus (Zimmermann 1780) is the most widelyIntroduction distributed and studied cervid in the American continent (Gallina et al. 2010). It is found from a latitude of 60º N in the south of Canada, through most of the United States, except some regions of the southeast, throughout Central America, and into South America in the north of Brazil and south of Peru at a latitude of 15º S (Smith 1991; Gallina et al. 2010). In Mexico this species is found throughout the country, except on the peninsula of Baja California and in some areas of northern Chihuahua and Sonora (Leopold 1959). The high levels of reproductive, behavioural and ecological plasticity observed in this species, are factors that have allowed it to expand its geographic distribution (Baker 1984). As a consequence, this browser cervid inhabits an extensive variety of different plant communities. In Mexico this species is found in temperate pine, oak and fir forests, mixed oak – pine forest, shrub land, tropical dry forest, semi-evergreen and evergreen forests, subaquatic vegetation and secondary vegetation (Galindo-Leal and Weber 2005). Thirty eight subspecies of the white-tailed deer have been described, 14 of which are found in Mexico (Smith 1991). Although the level of subspecies is frequently employed for conservation and management purposes, from a biological point of view its definition is controversial. Theoretically, subspecies are groups of local populations, within a species, that share a geographical range and common characteristics (genetic and phenotypic), that are adapted to the environmental conditions found in their habitat, and that are separated from other populations by some kind of geographical or climatic 42 THERYA Vol.1(1): 41-68 Salvador Mandujano, Christian A. Delfín-Alfonso and Sonia Gallina barrier; such qualities allow for the distinction of one subspecies from another (Frankham et al. 2002). However, the classification of the currently recognised white-tailed deer subspecies is entirely based on morphological characteristics (e.g., size, pelage colour, size and shape of male antlers), from just a few museum specimens (Kellogg 1956), and only a limited studies exist that present detailed or quantitative morphological or genetic data (e. g., Krausman et al. 1978; Sheffield et al. 1985; Cronin 1991a, 1991b; Mathews and Porter 1993; Ellsworth et al. 1994; Anderson et al. 2002; Van Den Bussche et al. 2002; DeYoung et al. 2002, 2003). For Mexico, very little information about morphometric or genetic variability in white-tailed deer is available. Studies exist for four north-eastern subspecies (Logan-Lopez et al. 2006, 2007), five subspecies in the country (Calderón-Lobato 2009), and three subspecies in the state of Michoacan (Chassin, personal communication). Fo (...truncated)