Ecología poblacional del ratón Peromyscus mexicanus (Rodentia: Muridae) en el Parque Nacional Volcán Poás, Costa Rica

Abstract

TheMexican Deer Mouse has been reported as an abundant wild mouse in Costa Rica; nevertheless, it has not been studied as well as other Peromyscus species. Thirty Sherman traps were placed on three habitats during six consecutive days of each month, from March 2002 through April 2003 in three sites of Poás volcano National Park, Costa Rica. A total of 2 393 mice were captured. Other species such as Reithrodontomys creper, R. rodriguezi, Scotinomys teguina and Oryzomys devius (Muridae) were also captured in Tierra Fría and R. creper,R.sumichrasti, S. teguina and O. devius in Potrero Grande. in Canto de las Aves we captured P. mexicanus, R. creper, R. rodriguezi and O. devius. Of the total mice collected, 34.77 % were P. mexicanus. For this species, the mean monthly capture per hectare was 34±2.15 in Tierra Fría and 11±1.85 in Potrero Grande. in the third site, Canto de las Aves, only four mice were captured throughout the study. The estimated population size did not change among months in Tierra Fría, but it did in Potrero Grande. No sex ratio variation was found in any habitat. in Potrero Grande, weight averages were 43.54±3.42 g for males and 42.08±3.4 5 g for females. variation in population structure among habitats was not significant. The presence of oak trees (Quercus sp.) and the high understory density could explain the stability of the population in this area.