@article{oai:soar-ir.repo.nii.ac.jp:00012029, author = {HANAZATO, Takayuki}, issue = {1}, journal = {信州大学理学部紀要}, month = {Oct}, note = {In outdoor experimental ponds, where overwintering individuals of zooplankton had been controlled with an insecticide, the following events were observed during winter and the following spring : (1) Daphnia survived through the winter as free-living individuals; (2) Daphnia ceased egg production in mid-winter, but restarted it in late winter or early spring; (3) the spring peak of the Daphnia population established by overwintering free-living individuals appeared nearly a month earlier than that by individuals hatched from resting eggs. Although resting eggs are often thought to play an important role in establishing spring populations of Daphnia, the experimental results suggest that overwintering free-living individuals can also contribute to it. The significance of the overwintering stages in Daphnia population dynamics is discussed., Article, 信州大学理学部紀要 35(1): 31-42(2000)}, pages = {31--42}, title = {Contribution of Resting Eggs and Overwintering Free-living Individuals to Establishment of Spring Daphnia Populations : A Suggestion Obtained from Studies using Experimental Ponds}, volume = {35}, year = {2000} }