TEMPERATURE ACCLIMATIZATION IN THE FILTERING RATES AND OXYGEN-CONSUMPTION OF DAPHNIA-AMBIGUA SCOURFIELD

1. 1. Filtering rates and oxygen consumption were measured in the field on a wild population of the fresh-water limnetic cladoceran Daphnia ambigua. 2. 2. Filtering rates increased with increasing body size and were significantly affected by environmental temperature. 3. 3. Oxygen consumption increased with increasing body size; there was no significant difference among b values determined at different environmental temperatures but bs were highest at low temperatures. decreased progressively at higher temperatures and increased at the highest temperatures. 4. 4. Temperature significantly affected the rate of oxygen consumption. 5. 5. Both filtering rates and oxygen consumption evidenced classical translation to the left in cold-acclimatized animals. An environmental temperature near 12°C apparently separates warm- and cold-acclimatization processes. © 1979.