Hatching intervals are generally from 1 to 3 days, quite often within 37–45 hours apart.
New chicks are semi-altricial (i.e. typically helpless and blind), initially being white and rather wet but dry by the end of the first day.
The weight of 7 hatchlings was 35 to 55 g (1.2 to 1.9 oz), with an average of 46 g (1.6 oz) while 3 were 44.7 g (1.58 oz).
Due to the pronounced asynchrony of the egg-laying and hatching, the size difference between siblings can be enormous and in some cases when the smallest chick weighs only 20 to 50 g (0.71 to 1.76 oz), the biggest chick already has attained a weight of around 350 to 380 g (12 to 13 oz).
When the oldest chick is about 3 weeks, the female will start to hunt as well as the male and both may directly feed the young although in some cases they may not need hunt very much if lemmings are particularly numerous.
Caches of lemmings around a nest may include more than 80 lemmings that can support the family.
Unlike many owls, the chicks of snowy owls are not known to behave aggressively toward one another or to engage in siblicide, perhaps in part due to the need for energy conservance.
Some cases of cannibalism of chicks by the family group were thought to be cases where chicks dies from other causes.
When they are about 2 weeks, the chicks may begin to walk around the nest site which they leave by 18–28 days, although they are still unable to fly and may find safety in nooks and crannies of vegetation and rocks usually only about 1 to 2 m (3.3 to 6.6 ft) from the nest mound, as well as via their parents defense.
Leaving the nest is thought to likely be an anti-predator strategy.
The male snowy owl may drop fresh prey deliveries directly on the ground near the wandering young.
After about three weeks of age, the young may wander fairly widely, rarely to 1 km (0.62 mi), but usually stay within 500 m (1,600 ft) of the nest mound.
Threat postures by young in reaction to researchers were first noticeable at about 20–25 days of age and common at about 28 days and the chicks can be impressively quick and agile-footed.
The first fledgling occurs at around 35–50 days, and by 50–60 days the young can fly well and hunt on their own.
The total care period is for 2–3.5 months, increasing in length with increased size of the brood.
Although independence was once thought to be sought by late August or early September but is more likely by late September to October when migration season for the species begins.
The nesting cycle is similar in length to the Arctic short-eared owls and faster than Eurasian eagle-owls by up to 2 months.
Hatching intervals are generally from 1 to 3 days, quite often within 37–45 hours apart. New chicks are semi-altricial (i.e. typically helpless and blind), initially being white and rather wet but dry by the end of the first day. The weight of 7 hatchlings was 35 to 55 g (1.2 to 1.9 oz), with an average of 46 g (1.6 oz) while 3 were 44.7 g (1.58 oz). Due to the pronounced asynchrony of the egg-laying and hatching, the size difference between siblings can be enormous and in some cases when the smallest chick weighs only 20 to 50 g (0.71 to 1.76 oz), the biggest chick already has attained a weight of around 350 to 380 g (12 to 13 oz). When the oldest chick is about 3 weeks, the female will start to hunt as well as the male and both may directly feed the young although in some cases they may not need hunt very much if lemmings are particularly numerous. Caches of lemmings around a nest may include more than 80 lemmings that can support the family. Unlike many owls, the chicks of snowy owls are not known to behave aggressively toward one another or to engage in siblicide, perhaps in part due to the need for energy conservance. Some cases of cannibalism of chicks by the family group were thought to be cases where chicks dies from other causes. When they are about 2 weeks, the chicks may begin to walk around the nest site which they leave by 18–28 days, although they are still unable to fly and may find safety in nooks and crannies of vegetation and rocks usually only about 1 to 2 m (3.3 to 6.6 ft) from the nest mound, as well as via their parents defense. Leaving the nest is thought to likely be an anti-predator strategy. The male snowy owl may drop fresh prey deliveries directly on the ground near the wandering young. After about three weeks of age, the young may wander fairly widely, rarely to 1 km (0.62 mi), but usually stay within 500 m (1,600 ft) of the nest mound. Threat postures by young in reaction to researchers were first noticeable at about 20–25 days of age and common at about 28 days and the chicks can be impressively quick and agile-footed. The first fledgling occurs at around 35–50 days, and by 50–60 days the young can fly well and hunt on their own. The total care period is for 2–3.5 months, increasing in length with increased size of the brood. Although independence was once thought to be sought by late August or early September but is more likely by late September to October when migration season for the species begins. The nesting cycle is similar in length to the Arctic short-eared owls and faster than Eurasian eagle-owls by up to 2 months.
Snowy owl