The breeding biology of the common redstart, Phoenicurus phoenicurus, was studied from 295 nests over 20 years in a nest-box population breeding in managed pine forest in the northeast of the Czech Republic, central Europe. The laying of first eggs lasted from 30 April until 30 June with two distinct peaks in May and June. The estimated proportion of pairs producing two broods per season was 65.4%, the highest estimate in studies of this species. Nest success was only 45.1%, one of the lowest known values. The mean clutch size was 6.30 eggs in assumed first broods and 5.39 eggs in assumed second broods. The production of two broods per season and relatively small clutches is probably a parental adaptation to conditions of frequent nest predation. The two breeding attempts per season could not, however, compensate for the latitudinal differences in clutch size and breeding success, and the seasonal breeding productivity was lower in comparison to populations in the northern area of distribution. At higher air temperatures the breeding started earlier. The air temperature also affected nest success which was highest at mean temperature values and decreased to both low and high temperature extremes. The effects of precipitation, first-egg-laying date, clutch size and year of observation on nest success were not significant.
Variation in nest survival rates is often ascribed to differences in predator communities. Because corvids are the dominant nest predators in many landscapes with fragmented woodland, their absence may have effect on both the overall nest success and its relationship to habitat features. Nest success of Sylvia atricapilla was examined in two habitats in agricultural landscape of SW Slovakia, where corvids were rare/absent. The daily nest survival rate (126 nests) was 0.977 (95% CI: 0.966–0.984) and 0.966 (0.948–0.977) for the egg and nestling stage, respectively, yielding a nest success of 0.52 (0.37–0.64) over a 24-day period. These values are higher than in comparable studies from central Europe, although predation was still the leading cause of nesting failure (more or equal to 71% of 48 failed nests). Correlational evidence suggests link between local absence of corvids and the relatively high nest survival, which was only weakly affected by nest site and habitat characteristics. Nest survival was not detectably higher in forest fragment than in windbreaks and did not increase with distance from forest-field edge or with vegetation concealment. We conclude that both the habitat features and composition of local predator community should be considered when explaining patterns in nest survival rate.