Native vegetation structure and persistence of endangered Tehuantepec jackrabbits in a neotropical savanna in Oaxaca, México
2009
Farías, Verónica | Fuller, T. K.
Because of its crucial importance for the persistence of the endangered Tehuantepec jackrabbit (Lepus flavigularis), we identified structural characteristics of native vegetation (1) selected by Tehuantepec jackrabbits to establish home ranges, (2) used within home ranges, and (3) in relation to activity and inactivity periods. A neotropical savanna in the Isthmus of Tehuantepec, Oaxaca, México, offered diversity in native flora and heterogeneity in vegetation structure to the studied population of Tehuantepec jackrabbit. Adults and juveniles differed in habitat use patterns. No effect on habitat selection was detected for sex or season. Jackrabbits established home ranges on grassy habitat with discontinuous overstory of nanche (Byrsonima crassifolia) shrubbery and morro (Crescentia) trees. Adults underused dense vegetation where predators may ambush them; juveniles avoided dense vegetation and grassland without overstory. Within adults' home ranges, habitat selection favoring grassy habitats with nanche and morro was relatively stronger during the activity period (nocturnal and crepuscular hours) and during one of 2 years which had more rainfall. Scattered trees and open shrubbery likely allowed foraging jackrabbits with both visibility and escape routes used to detect and outrun predators. Moreover, during the inactivity period (diurnal hours) adults and juveniles favored nanche shrubbery that provided resting jackrabbits with shelter to hide from predators. Clearly, structure and diversity of native vegetation in the savanna needs to be preserved for conservation of Tehuantepec jackrabbits because deteriorated habitat may pose higher predation rates for a jackrabbit population in risk of extirpation.
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