Este trabalho foi conduzido de julho de 2001 a junho de 2002 em uma plantação de cana-de-açúcar em Oratórios, Minas Gerais, Brasil, objetivando investigar o impacto de uma queima controlada de baixa intensidade (235,26 kcal.s-1.m-1) da palhada seca de cana-de-açúcar sobre a atividade forrageadora de A. bisphaerica. Durante todo o período do estudo, uma correlação negativa entre o fluxo de operárias transportadoras de carga vegetal para o ninho com temperatura e com umidade relativa do ar foi observada. Meses com menores quantidades de dias com chuvas apresentaram maior fluxo de operárias transportadoras de cargas. A atividade forrageadora foi reiniciada somente 15 dias depois da queima da palhada, com padrão de forrageamento similar ao observado em colônia localizada em área não queimada. Entretanto, por dia, estimou-se que 518,0 g e 670,0 g de folhas frescas de vegetal não entraram para o interior dos ninhos durante esses 15 dias. Isso, de alguma maneira, deve ter comprometido o desenvolvimento dessas colônias.

This work was conducted from July 2001 to June 2002 in a sugarcane plantation in Oratórios, Minas Gerais, Brazil, with the objective of studying the impact of low intensity controlled fire (235.26 kcal.s-1.m-1) of sugarcane dry foliage on the foraging activity of A. bisphaerica. During the entire period the present study, a negative correlation between ant flow in the trail and temperature and air humidity was observed. Days without rain also increased ant workers' flow. Foraging activity was reassumed in the trail only 15 days after burning and showed a pattern similar to that of a colony located at an unburned area. However, an estimated of 518.0 to 670.0 g of freshly cut vegetation per day did not enter the nest during the recovery period. This certainly could reflect in losses for colony development.

Seven nests of T. fuscus Emery, 1834 have been studied for their structure. These nests, which opened at the soil surface, had two to four chambers located one above the other. Externally all of these nests presented a heap of brownish-yellow debris that was constituted basically by remains of vegetable material. The total nest population was, on average, 1,048 individuais. The diel pattern of foraging of this species was studied for four consecuti ve months on two nests. This activity occurred predominantly in the night period, and the workers transported, mainly, dry vegetation to the nest.