ABSTRACT A two-year collecting programme, carried out in the Guinea Savanna in the Wa area, north-west Ghana, produced a total of 480 snakes of 37 species. As part of this programme, routine night-collecting by motorcycle and on foot, produced 190 specimens of 22 nocturnal species. Both seasonal and daily activity patterns in several species were noted. Activity patterns were strongly affected by temperature and rainfall. Preference for different temperature/climatic regimes appear to separate certain species that would otherwise possibly compete.