The Feeding of Amebae on Algae in Culture 1

SUMMARY Amebae differed greatly in their ability to prey on algae. Species of Chlamydomonas, Pandorina, Anabaena, Ourococcus, Ankistrodesmus, and Gloeocystis were utilized by 3 or all 4 of the test protozoa, while strains of Staurastrum and Chlorella would not support growth of the predators. Heating the cells of Chlorella sp. rendered them available to the 4 amebae and made Pandorina morum a better nutrient for some of the protozoa. Heating Chlamydomonas oblonga had no effect on its availability to Tetramituis rostratus and reduced its suitability as a food source for Amoeba discoides. The rate of protozoan feeding was also influenced by temperature, pH, and age of the algal prey.