Transects to Estimate the Number of Leaf-Cutting Ant Nests (Hymenoptera: Formicidae) in Eucalyptus urophylla Plantations

摘要

Five stands of Eucalyptus urophyllawere used to simulate transects at different distances and initiated in different planting lines to propose a procedure to estimate the number of nests of leaf-cutting ants. The number of nests found with transects at different intervals was used to test their correlations with the census per stand of eucalyptus. Transects with different distances between each of them presented significant correlation with the census. Eucalyptus stands with higher density presenteda more uniform distribution of nests of leaf-cutting ants which makes it possible to use larger distances between transects. On the other hand, these nests tend to present a random distribution in areas with low densities which makes it necessary to sample a larger area. The density of nests of leaf-cutting ants and the error with each distance between transects with significant correlation and the standard deviation of each parameter showed that the transects should be used every 150 meters to estimatethe number of nests of these pests. Additionally, they should be initiated at the seventh planting line and the data used in a regression linear model for the numbers of nests of leaf-cutting ants sampled. On the other hand transects should be used every 210 meters in plantations after two years without indication of control of these pests.