PARENT SESSION
Poster Session 24: Agro-Ecology
Wednesday, August 10, 5:00 PM - 6:30 PM, Exhibit Hall 220 A-E, Level 2, Palais des congrès de Montréal
Carrion beetle distribution in an agricultural landscape in Hidalgo, Mexico: the role of forest remnants and food availability.
Hernandez-Hernandez, Juan1, Castellanos, Ignacio*,1, Martinez-Morales, Miguel1, Moreno, Claudia1, Sanchez-Rojas, Gerardo1, Zuria, Iriana1, 1 Universidad Autonoma del Estado de Hidalgo, Pachuca, Hidalgo, Mexico
ABSTRACT- Forest remnants are abundant elements in many agricultural landscapes of central Mexico and may represent a valuable habitat for several insect species. Despite their abundance, the role of these landscape elements in determining species composition and abundance has not been studied in much detail. We used carrion-baited traps to study the distribution and abundance of a particular group of beetles, primary carrion decomposers (Silphidae), in a 700 ha agricultural landscape with oak-pine forest remnants embedded in a matrix of corn fields. Beetles were sampled along transects located in both, the forest fragments and the agricultural fields. We also investigated whether there was a relationship between number of beetles and indices of food availability (birds, reptiles and mammal abundances). We found that three species of silphids (Thanatophilus graniger, T. truncatus and Nicrophorus mexicanus) were present in both habitat types (forest remnants and agricultural fields). However, the abundances of T. graniger and T. truncatus were significantly higher in agricultural fields than in forest fragments. In contrast, the abundance of N. mexicanus did not differ significantly between both habitat types. We found a significant and positive correlation between available food resources (vertebrate biomass) and the abundance of T. graniger and T. truncatus in the agricultural fields, but did not find a significant correlation between the abundance of N. mexicanus and available food resources. Our results show that the three species of silphids use forest fragments and agricultural fields, however, both species of Thanatophilus appear to prefer agricultural fields in places where food availability is highest, while N. mexicanus appears to be a generalist species that is not associated with food resources.
Key words: fragmentation, Mexico, Silphidae