Nothing says spring quite like little beaks clamoring to be fed.
These unobtrusive cameras offer both scientists and the general public a valuable window into birds' tantrums, messy meals, and sibling rivalry. (Related: "Five Bald Eagle Cams to Watch Now.")
Some of these youngsters have been living large for weeks now, while others are too small to do much but snuggle under mom and dad.
To avoid disturbing these new families, the cameras illuminate nests with infrared light, which birds aren’t able to see.
Here's our pick for the season's best nest cams.
Bald Eagles at Mount Berry, Georgia
These bald eagles, which live in a city northwest of Atlanta, feed fish and small rodents to their six-week-old eaglets, which can handle only beak-size portions.
The older, larger eaglet is the dominant sibling, which means that it's more aggressive and is usually fed first. Like any younger sibling, the other eaglet doesn't take this lying down, and will jostle for the first mouthful. (See our favorite pictures of bald eagles.)
After eating, the eaglets doze off, necks drooping limply over the side of the nest.
Like any baby, bald eaglets need time to digest and sleep, says Jim Elliott of the Avian Conservation Center in South Carolina.
Bald Eagles at Crow River, Southern Minnesota
In Minnesota, eaglets from another family have yet to break out of their shells. Northern eagles usually lay their eggs later than southern eagles do; these ones were laid on February 28 and March 3.
Bald eagle eggs usually incubate for about 35 days, so these babies will hatch around the first week of April. Until then, the parent birds will take turns incubating the eggs and keeping other nesting eagles out of their territory. (See eagles like never before in National Geographic magazine.)
Bald eagles don't attack each others' eggs, says Elliott, so this behavior is mainly to protect good nesting and hunting spots.
Nests can be reused for several years, and bald eagles sometimes compete with great horned owls for prime real estate.
Great Horned Owls in Savannah, Georgia
These great horned owlets are big enough to be left home alone. At about eight weeks old, they're growing independent and have started to roam the branches around the nest. (See our favorite bird pictures.)
Great horned owls can swallow small prey whole, and watching an owlet wolf down a small rodent is quite an impressive sight.
If something disturbs the owlets, you'll see them puff up and arch their wings to appear as large as possible. This can be a response to a threat, but the owlets probably aren't in real danger, according to experts.
"As a young owl, you might use that behavior for something when you don't know what it is," says Denver Holt of the Owl Research Institute in Montana.
Like a curious crow peeking into your nest.
Barn Owls in Bay Area, California
Are owlets cheaper by the half dozen? For barn owls, six is just an average-size brood. These owlets, between two and four weeks old, seem to spend most of their time getting in each other's way.
There's always a lot of excitement when the father brings prey back to his family. Mom rips meat off the carcasses to feed her clamoring owlets, who aren't shy about grabbing for the best bits. (Read why barn owls divorce.)
Six baby owls means one messy nest, but the feathers and owl pellets—clumps of undigested food—can keep owlets warm, says Sofi Hindmarch, an independent owl researcher in British Columbia, Canada.
When these owls fly the nest, the box can be readied to house a new feathered family.
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