Effect of temperature on growth and ingestion rates of Favella sp

This study describes the effect of temperature on the growthand ingestion rates of the tintinnid, Favella sp. cultured withthe dinoflagellate Heterocapsa triquetra. In vivo fluorescencewas used to monitor the change in density of the H. triquetrapopulation over 4- to 5-day periods in control tubes containingonly algae, and in experimental tubes containing algae and tintinnids.A ‘switchover point’ occurred in the temperaturedependency of the growth rate such that below 11.4°C, H.triquetra grew more quickly than Favella sp. and above thistemperature the situation was reversed. Ingestion rates of Favellaon H. triquetra were found to be temperature dependent in anonlinear fashion. The rate doubled (from 2.5 to 5.3 cells animal^–1h^–1) between 11.4 and 16.4°C whereas there was nochange in ingestion rates between 8.0 and 11.4°C, or between16.4 and 21.1°C.