The population of Myrmica ants, which is most abundant in high altitudinal areas in South Korea, is expected to
decrease significantly due to climatic warming, whereas Aphaenogaster japonica population is expected to increase
in these areas. The two ant groups are similar in shape, size, and ecology, indicating intensive competition
in overlapping areas. To determine the foraging activities of the two groups and their competitions, I investigated
the ants at a high mountain (Mt. Gyebangsan) during two ant foraging seasons (2010 and 2011) using pitfall
traps and bait traps along altitudinal gradients. Two Myrmica species (kotokui and kurokii) were present between
800 m to 1577 m, whereas A. japonica appeared up to 1200 m. Fights between ants were observed 22 times and
fights between these two ant groups were most frequently found. Food discovery speed is higher in Myrmica
species than in A. japonica. The food discovery capability and the nestmate recruitment were not different
between A. japonica and Myrmica species