Figure 3

Density of host hatchlings in spring in the epidemiological experiment. Mean spring density and standard errors of Daphnia magna hatchlings in experimental populations either uninfected or infected with the microsporidium Hamiltosporidium tvärminnensis. Host populations differed in the initial parasite prevalence in April 2002 (0%: n = 14, 5%: n = 10, 50%: n = 10 or 100%: n = 10) and were kept under outdoor conditions. Hatchling densities were estimated in 2004 and 2005 after hatchlings had been detected in all populations.