Growth of Atta laevigata (Hymenoptera : Formicidae) nests in pine plantations

We evaluated the survival, mortality and colony growth over time after work er emergence in colonies of Atta laevigata (Fr. Smith) ants in young pine t ree plantations of Pinus caribaea (Mor) located in Estado Monagas, Venezuel a. One hundred forty-four colonies were inspected during a 41-month period. Colony mortality one month after worker emergence was 45%. A small mortali ty peak was evidenced when colonies were 24 months old, coinciding with a d ry season. About 23% of the colonies marked survived more than 3 years. Dur ing the first two years, colony growth was faster than during the next two years, as measured by the total number of nest entrances and the nest surfa ce area. Multiple regression analyses showed a closer correlation between n est age and nest area than between nest age and number of nest entrances. M ost of the nests grew in an eccentric way with respect to the site where th e queen first established the nest. These results allow for a more rational pest management of pine plantations by using the knowledge on nest growth for decisions on pest control.