Asian Myrmecology, Volume 2, Behaviour
Observations on the foraging behaviour of Myrmicaria brunnea subcarinata (Smith) (Hymenoptera: Formicidae) in a tropical rainforest in Sarawak (Malaysia)
JAN WRIEDT 1, DIRK MEZGER 1, LUCY CHONG 2 & MARTIN PFEIFFER 1
1 University of Ulm, Department of Experimental Ecology, Albert-Einstein Allee 11, 89069 Ulm,
Germany
2 Forest Research Centre, Sarawak Forestry Corporation, Kuching 6 Mile Jalan Datuk Amar Kalong
Ningkan, Sarawak 93250, Malaysia
Abstract. As a contribution to the knowledge of the natural history of Myrmicaria
brunnea subcarinata (Smith, 1857), we studied the territory, circadian activity patterns,
diet composition, trophobiotic interactions and fighting success of a colony of this
species in an alluvial forest in Gunung Mulu National Park (Borneo, Malaysia). The
territory size of the focal colony, which comprised 6,000 to 8,000 individuals living
within a single nest, was approximately 270 m2. Many permanent foraging trails were
subterranean and total observed trail length was about 44 m. Ants were active at the
nest throughout the 24-hour cycle, with increased foraging activity during the night.
The food spectrum of the species included mostly animal prey, but also herb particles
and plant juice. Additionally, M. brunnea subcarinata was found in trophobioses
with several bugs (Coreinae) and other hemipteran species at stems of the climbing
bamboo Dinochloa trichogona and other plant species. Observations at baits showed
that the species defended resources successfully in about 2/3 of all experimental
interactions, with Pheidologeton affinis being its most effective competitor.
Keywords: Borneo, competition, foraging activity, Myrmicinae, territoriality, trail
system, trophobiosis, tropical rainforest