title: Egg age distribution, the direct way to cladoceran birth rates.
abstract: Cladoceran hatching frequency can easily be calculated from observed egg age distribution and estimated egg development time. The large timelag errors of models incorporating birth rates in the equation are avoided, and the population growth rate can be estimated directly.
authors.affiliation: Dept. of Animal Ecology, Zoological Museum, University of Bergen, 5000, Bergen, Norway.
authors.forename: Geir
authors.initials: G
authors.lastname: Johnsen