The effects of temperature on development and growth are described for the common Cladocera and Copepoda in Tjeukemeer. Eight cladoceran species and five copepod species have been investigated: Daphnia hyalina, Daphnia cucullafa, Bosmina coregoni, Bosmina longirostris, Chydorus sphaericiis, Ceriodaphnia pulchella, Diaphanosoma brachyurum, Leptodora kindtU, Acanthocyclops robustus, Mesocyclops leuckarli, Diacyclops bicuspidatus, Cvclops vicinus vicinus and Eurytemora affinls. Growth is expressed as length increment per size class (cladocerans) or instar (copepods) per week and as the relationship between time and length. The curvilinear logarithmic equation: \n D ~ \T\ a + b {\w TY is fitted to the development times of eggs, combined naupliar instars and combined copepodite instars, as well as to the longevity of the adults. The results are compared with those found in the literature and differences are discussed.

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This review deals with culture techniques in use to estimate individual growth, development and reproduction of copepods and cladoeerans in cultures. The conceptual aspects of growth, reproduction and feeding behaviour are briefly summarized. Marine copepods are included, because the techniques employed for the cultivation of these animals are often more advanced than those used for freshwater crustaceans. Most of the studies reviewed here were carried out under defined laboratory conditions, but a few were under field conditions, generally in small in situ enclosures. The culture methods described in this review are based on 272 studies published between 1910 and 1987. A large number of different culture systems are critically discussed in relation to culture conditions and culture techniques and the taxa used. Particular attention is given to the effect of food quality, and the problem of how to apply laboratory measurements to field populations so as to limit errors to the minimum. A more detailed summary is given in the section on 'Recommendations' at the end of the review.

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As part of a research programme on the food chains in Tjeukemeer, the Daphnia hyalina and Daphnia cucullata populations were studied for three successive years . To analyse the factors regulating the production of these two species, their population parameters density, size distribution, fecundity) and population dynamics birth rate, mortality rate) were studied and related to environmental factors . Since Daphnia in Tjeukemeer shows continuous recruitment, the population dynamics model 'INSTAR' was developed and used to integrate field data with laboratory data on development rates and length-weight relationships . The dynamics of the Daphnia species are mainly regulated by temperature and fish predation, the latter affects both birth rate and mortality . Total annual Daphnia production was 3 .1-6.9 g org . dry wt m-2 , and annual P/ B ratio ranged from 25 to 40 for D . cucullata and from 45 to 49 for D . hyalina.

To study experimentally the relation between zooplankton and phytoplankton, laboratory cultures of Daphnia hyalina Leydig were set up. The combined influence of food quality and quantity on growth, birth-rate and longevity was measured. The effect of seven different food regimes was tested. Natural unfiltered lake water from the eutrophic lake Tjeukemeer was used in one regime. The food value of the natural unfiltered lake water appeared to be relatively low, which was most likely caused by the abundance of large sized algae in the lake water.