The Zooplankton of Ösbysjön, Djursholm: II. Further Ecological Aspects

Abstract

During late winter the zooplankton is at a minimum, presumably because of the low oxygen content of the water (or conditions connected with this). During spring, the environment becomes more favorable for zooplankton, resulting in a rapid increase. Different populations often increase simultaneously, indicating that competition is not especially hard at that time, presumably because of a superabundance of food. However, not all forms coincide in the time for their maximum population increase, and a certain succession can thus be noted. Responsible for this are such factors as temperature dependence, reproductive rate and choice of food.