Did You Know That Baby Birds Grow Super-Fast?
Contributed by Alaska Wildbird Rehabilitation Center
Robins are altricial, with an incubation period of 12–14 days. They stay in the nest for 9–16 days, fledge at about ¾ the size of an adult, cannot fly when they leave the nest, and are independent after 31–45 days. Swallows are also altricial, with an incubation of 11–20 days. They stay in the nest 15–25 days, are full size at fledge, can fly when they leave the nest, and are independent by 25–30 days. Mallards are precocial, incubate for 23–30 days, leave the nest within 13–16 hours, are full size, cannot fly at fledge, and are independent by 50–60 days. Ravens, also altricial, incubate 20–25 days, remain in the nest 28–50 days, are full size at fledge, cannot fly, and are independent at about 6 months.
Altricial: born in a helpless state, needing parental care for nourishment, protection, and warmth (i.e. humans, bunnies, cats, dogs and a lot of birds). Precocial: young are relatively mature and mobile, able to feed themselves and move around soon after birth (i.e. snowshoe hare, ducks, moose). This does not mean they do not require something from their parents—in mammals, they require milk, and most precocial young receive protection, warmth and knowledge from their parent(s).
Not all birds that fledge are incapable of flight. Several species (swallows, swifts, martins) can fly when they fledge. The best thing we can do during this time is keep pet cats inside, in a catio, or on a harness. Cats are natural hunters and will easily catch a fledgling bird. Don’t be fooled—cats eat birds, not just mice. Dogs may also pick up young birds, and even if not bitten, the bird may be stressed and covered in saliva.
Please call us if you see a bird in need. We’ll assess the situation and may ask you to text a photo and location. Unless the bird is in clear danger (ducklings in the road, a gull with a bloody wing), call before intervening. Remember—it’s a bird-eat-bird world, and all birds must feed themselves and their young.
More info and HOTLINE: 907-892-AWBR (2927) or visit akwildbird.org