THE EFFECT OF PH ON FEEDING-BEHAVIOR IN NEWT LARVAE (TRITURUS, AMPHIBIA)

The feeding responses of three species of newt larvae were compared un der circumneutral and sublethal acid conditions. Under acid conditions (pH 4-5) feeding behaviour was suppressed in palmate newts, Triturus helveticus, and smooth newts, T. vulgaris, but not in crested newts, T . cristatus. At low pH, approach and orientation towards food occurred in T. helveticus and T. vulgaris, but snapping was inhibited; T. cris tatus snapped and consumed food immediately it was offered under the s ame conditions. These differences are not consistent with the apparent greater tolerance of T. helveticus for acidified ponds. The observati ons suggest that the chemosensory system of T. helveticus and T. vulga ris may be impaired at low pH.