House Wren BabiesWiki info
Depending on the exact population, the house wrens' clutch is usually between two and eight red-blotched cream-white eggs, weighing about 1. 4 g (0. 049 oz) each and measuring c. 17 and 13. 4 mm (0. 67 and 0. 53 in) at the widest points. Only the female incubates these, for around 12–19 days, and she will every now and then leave the nest for various reasons. While she is on the nest, the male provisions her with food. The young, which like all passerines hatch almost naked and helpless, take another 15–19 days or so to fledge . They are being fed by both parents, and need plenty of food given their tiny size (see also Bergmann's Rule). As the young near fledging, the parents spend much of their time procuring food for them. Brood loss due to predation was found to be light in the Southern Andean Yungas, with predation of nestling young being almost insignificant. Known predators of house wrens at the nest include cats, rats, opossums, woodpeckers, foxes, raccoons, squirrels, snakes and owls. Adults away from the nests can usually avoid these predators although both small hawks and owls occasionally take free-flying adult wrens.