Ant Occupation of Twigs in the Leaf Litter of the Atlantic Forest: Influence of the Environment and External Twig Structure

• Published in: Tropical conservation science Vol. 12; no. 1
• Main Authors: Fernandes, Tae Tanaami, Dáttilo, Wesley, Silva, Rogério R, Luna, Pedro, Oliveira, Carla M, Morini, Maria Santina de Castro
• Format: Journal Article
• Language: English
• Published: Sage CA: Los Angeles, CA SAGE Publications 01.05.2019; SAGE PUBLICATIONS, INC
• Subjects: Animal behavior; ant communities; ant nesting; Ants; Atlantic forest; Canopies; Colonies; conservation; Diameters; Filters; Forests; Herbivores; Leaf litter; Leaves; Microhabitats; Moisture; Morphology; Nesting; Physical characteristics; Species diversity; Species richness; tropical diversity; tropical diversity; Atlantic forest; ant nesting; ant communities; conservation
• ISSN: 1940-0829; 1940-0829
• DOI: 10.1177/1940082919852943

Twig cavities are microhabitats that may be used by different ant species for nesting and colony expansion. However, ants do not colonize all twigs available in the leaf litter, pointing to the existence of environmental or twig-related filters. In this study, we analyzed which environmental and twig attributes affected twig occupation by ants. We surveyed seven plots in six Atlantic forest sites in southeastern Brazil. To characterize the environmental filters, we quantified canopy cover and leaf litter moisture and depth. At the twig level, we measured twig length and diameter and the area and circumference of all holes in each twig. Ant colonies occupied 13.42% of the 4,805 twigs surveyed, and we recorded a total of 52 twig-nesting ant species. Brachymyrmex admotus was the most frequent species. Ant species richness increased with canopy cover and leaf litter moisture and with the relative number of occupied twigs. In addition, we found that ant species richness increased with length and diameter of the twigs, and that twigs with smaller holes were more frequently occupied by ants, regardless of the availability of larger diameter holes. Our work demonstrates that both environmental characteristics and twig morphology can structure occupation of twigs by ants. In addition, we demonstrated that certain species show a preference for certain twig types. We highlight the importance of twigs for maintaining ant diversity and for colony expansion of arboreal species and species inhabiting the leaf litter.