Variation in leaf-cutter ant (Atta sp.) densities in forest isolates: the potential role of predation

The potential role of predation as a factor underlying variation in leaf-cutter ant ( Atta sp.) densities was investigated on recently isolated land-bridge islands in Lago Guri, Venezuela. A survey of mature Atta colonies revealed a sharp increase in densities on small and medium islands (5.6 and 2.3 colonies ha −1 respectively) compared to large islands (0.72 colonies ha −1 ) and the mainland (0 nests in 5.5 ha). Incipient colonies showed the...