SEASONAL AND SPATIAL PATTERNS IN-GROUND FORAGING ANTS IN A RAIN-FOREST IN THE WESTERN GHATS, INDIA

Seasonal variation and spatial distribution in ground foraging rain fo rest ants were studied in South Kannada-Kodagu District in Karnataka ( India) between 1990 and 1991 by pie-fall trap sampling. All ant specie s showed marked seasonality. A total of 31 species were recorded from the primary forest over a period of two years. More species were recor ded from the closed canopy forest than from tree fall gaps in primary forest. All ant species showed marked seasonality with fewer species a nd individuals sampled/plot during the wetter seasons. The numerically dominant species, Pheidole sp,. was markedly lower in abundance durin g the wet seasons. Spatial patterns were also studied during a dry sea son both in the primary forest and an adjacent logged forest. More spe cies were recorded from the logged forest than the primary forest. Com munity composition in primary forest was different from that in logged forest. Common species were more ubiquitous than rarer species. Speci es were distributed bimodally across sampling plots. Probable underlyi ng processes behind these seasonal and spatial patterns have been disc ussed.