Abstract

NORIEGA A, JORGE ARI; CUBILLOS, ANA MARIA; CASTANEDA, CAMILO  and  SANCHEZ, ANA MARIA. Daily colonization of food resourses by Dung Beetles (Coleoptera: Scarabaeidae) in the Colombian Amazone Region. Acta biol.Colomb. [online]. 2008, vol.13, n.3, pp.73-84. ISSN 0120-548X.

Dung beetles belonging to the Scarabaeidae family have strong competition for food resources given the low spatial aggregation and ephemeral character of those resources. Temporal segregation through specialization in hours of activity is a mechanism that can decrease that competition. The objective of this paper is study the daily activity of an assemblage of dung beetles in a tropical wet forest in the colombian amazon. During the dry season, two linear transects of 225 m were established, with 10 pitfall traps mounted for 24 hours, baited with human excrement of two researchers. Trap contents were collected hourly. 23 total species were recorded, within 10 genera and 5 tribes. The abundance of the diggers guild were higher then the others groups. Diurnal beetles were more abundant than nocturnal and crepuscular species. Some species with very specific hours of activity were present, evidencing the problem of allowing a long time between collections, thus losing the detail of restricted activity. Differences existed in the abundance and richness of species on the bait, implying that there can be variations between human excrement. Finally, it was shown that restriction in daily activity can be an important mechanism for diminishing inter and intra specific competition, which facilitates the coexistence of species and the division over the resource in time.

Keywords : Daily activity; dung beetles; assemblage; colombian amazon.