LAUSR

We described the effects of fire ants (Solenopsis saevissima) (Hymenoptera: Formicidae) on and in a big-eared opossum (Mammalia: Marsupialia: Dedelphidae) carcass. The observations were made in southeastern Brazil beside of a public highway. We documented the competitive ability of the fire ants, which sought to reduce competition with necrophagous flies by constructing a soil structure over the natural orifices of the carcass. After we removed the structure, the ants changed their physical and ecological behavior on the carcass until the end of decomposition. This ant behavior of blocking access to the carcass delays the decomposition process due to the fact that other necrophagous insects cannot forage there.