Variability of daily nest survival and breeding success in relation to characteristics of Eurasian magpie (Pica pica) nests

Size and structure of birds’ nests can arise from evolutionary trade-offs between benefits, such as insulation from unfavourable conditions, maintenance of eggs or chicks, security against predation, and costs, such as energy spent in construction of the nest and the risk of predation in more visible nests. The relationships between nest characteristics and breeding success and survival probabilities of Eurasian magpie (Pica pica) eggs and nestlings were studied in Baghbadaran, central Iran during the 2008 and 2010 breeding seasons. Nesting success was modelled to assess the relationships between nest parameters and the probability of daily nest survival. Mean clutch and brood size, hatching, fledging and breeding success did not vary significantly between the two years. Mean internal diameter, external diameter, distance to feeding location and distance to open areas varied significantly between the two study years. Daily nest survival rate for both years (2008 and 2010) was 0.98 ± 0.002. Nest size and s...