SOME ASPECTS OF BEHAVIOR OF OYSTERS AT DIFFERENT TEMPERATURES

Abstract

1. Some adult Long Island Sound oysters are able to pump water at a temperature as low as about 1.0° C. Oysters with crystalline style and food in their stomachs may occasionally be found in northern waters in winter.2. Approximately 15 per cent of the oysters exposed to temperatures ranging from 2.0° to 3.0° C., and approximately 50 per cent of the oysters kept between 3.0° and 4.0° C. formed pseudo feces.3. The average and maximum rates of pumping of the groups of oysters exposed to temperatures from 0.0° to 38.0° C. were determined. The rate remained low under 8.0° C. Within the range from 8.1° to 16.0° C. the rate steadily increased. Between that point and about 28.0° C. the rate showed no marked fluctuation. A further increase was noted between 28.1° and 32.0° C. It is within this range that the maximum average rate of pumping of 12,983 cc. per hour was recorded. Between 32.1° and 34.0° C. the rate was also rapid. Beyond 34.1° C. the oysters showed a marked decrease in the rate of pumping and their s...