The contribution of the bark of isolated trees as habitat for ants in an urban landscape

Since urbanisation and fragmentation result in a decrease in larger forests, the importance of isolated trees as habitat in urban landscapes is increasing. This study investigated the contribution of trees in urban landscapes to the abundance and variety of arthropod taxa. Ants and other arthropods were surveyed on the bark of 341 trees in three types of arrangement: isolated trees, trees in linear corridors and trees in patches. Ant species and other arthropods were identified and the numbers on each tree were counted. In order to determine the effects of host tree properties (size and plant species) and the surrounding environment (arrangement of trees, surrounding land cover), an analysis of covariance was conducted. Tree species was the most important influence, followed by tree size, on ants and other arthropods in the urban landscape, with little effect from the arrangement of trees. Thus, in order to increase arthropod diversity in urban landscapes, it is important to select tree species that attract a large number of arthropod taxa.