The breeding biology of the house sparrow Passer domesticus in Israel

Egg laying occurred from the end of March until mid July. Mean clutch size was 5.05 eggs (modal clutch size 5) whereas the most productive clutch size was 6 eggs. On average each pair laid 2.3 clutches per year from which a total of 5.75 young fledged. Mean egg weight increased with laying sequence within the clutch. Incubation length was negatively correlated with ambient temperature. Average breeding success was 70.0%. Nestling growth rate was negatively correlated with brood size, but both time the nestlings spend in the nest and nestling feeding rate were positively correlated with brood size. Time interval between broods increased by on average 1.6 d for each additional chick raised in the previous brood. -from Authors