It’s spring, and baby birds will soon be chirping in trees and rain gutters. But not all bird nests are created equal. Whether from mud, leaves, or saliva, here are 10 birds that make some of the most astounding structures in nature.
1. Sociable Weavers build giant haystacks in African trees.
This massive structure may look like a hay bale, but it’s actually a hive of nests. Like an apartment complex, it can house up to 400 Sociable Weavers. The thatched roof protects the birds in the South African or Namibian deserts by keeping the heat out by day and insulating from cold at night. Since the birds use the structure for generations, a nest can get up to 100 years old—that is, if it doesn’t break the tree limb first.
2. Malleefowl make giant mounds out of bird-made compost.
The nesting mound of the Australian Malleefowl is among the biggest in the world. The record was 15 feet high and 35 feet across, according to Guinness World Records. To make the mound, the male bird digs a hole and fills it with organic matter such as leaves, sticks, and bark. He even turns the compost to speed decay, just like a gardener. When the compost heats up to 89 to 93 degrees, the female lays up to 18 eggs on it, one at a time. The eggs are covered in sand. During incubation, the male regulates the temperature of the mound using his beak like a thermometer. Despite all this, Malleefowl abandon their chicks as soon as they’re born.
3. Golden-headed Cisticolas sew like tailors.
The Golden-headed Cisticola from Australia uses spiderwebs to sew a living canopy out of leaves. Since the bird’s nest is only 20 inches off the ground, the camouflage protects it from predators. To make the canopy, the bird pierces the leaves with its needle-like beak and pulls a “thread” through to hold them together. This cozy cover anchors the nest so that it stays hidden as the plant grows.
4. Black Kites use trash to decorate their nests.
Black Kites in Europe have adapted to humans by decorating their nests with strips of white plastic. While some scientists believe this is to camouflage the eggs, new research suggests that the plastic is really there to show off for other Black Kites. According to this theory, Black Kites view trash as a statement of power, like having a big house on a hill is to humans. Apparently, these birds take after people in more ways than one.
5. Edible-nest Swiftlets build nests out of saliva
In caves in Southeast Asia, Edible-nest Swiftlets make cliffside nests out of layers of their own spit. The saliva sticks to the rock and hardens in a bracket shape that the bird uses to lay its eggs. The nests are also a sought-after delicacy for bird’s nest soup. They have no flavor and no nutritional content, but this doesn’t prevent them from being one of the most expensive foods in the world. People are so crazy for it that many countries regulate the bird nest industry to keep the swiftlet from dying out.
6. Rufous Hornero nests look like outdoor ovens
The Rufous Hornero in South America is an ovenbird, so nicknamed because of how it makes its nest. The bird collects mud and manure and piles it into an upside-down bowl on a tree branch. The sun bakes the mud dry, making a sturdy structure resembling a clay oven. Since the birds build a new nest for every brood, there are often several mud nests in a row on the same branch, all made by the same birds.
7. Montezuma Oropendola nests look like hanging sacks.
These birds from Central America weave pendulous nests out of vines and banana fibers. The nests can be 3 to 6 feet long and look like a ball hanging in a stocking. Since the birds live in colonies, there can be up to 150 of these nests extended from one tree, although usually it's more like 30. The female takes 9 to 11 days to make her nest. The male often watches her work, and if he doesn't like what he sees, he'll tear it apart and make her start over.
8. One Gyrfalcon nest was around when Jesus was alive.
The Gyrfalcon (pronounced JER-fal-con) is a large white falcon that nests in cliffs in the Arctic. They use the same depression or scrape in the rock generation after generation. In 2009, researchers from the University of Oxford did radiocarbon dating on a Gyrfalcon nest and found that it was around 2500 years old. Three other nests were over 1000 years old, and fragments of gyrfalcon feathers were 600 years old. The birds have been continually using the nest since the Roman era.
9. Bald Eagle nests are huge.
In true American style, Bald Eagles make nests far bigger than their needs would seem to indicate. When they first mate, the eagles make smaller nests, or aeries, 50 to 125 feet above the ground by layering branches and sticks in a triangular pattern. Every year, they add more to the nest until it becomes big enough for a human to sit on. The largest bird nest on record was a Bald Eagle nest found in St. Petersburg, Florida in 1963. It was 10 feet wide and 20 feet deep.
10. Hummingbird nests are tiny (and adorable).
On the other end of the scale, hummingbird nests are so small that it’s easy to mistake them for knots in the trees. In fact, the smallest nest in the world is the Bee Hummingbird's nest, which is just over an inch wide. The hummingbird makes its cup-shaped nest by weaving spiderwebs with feathers and leaves to make it strong and stretchy, then covering the outside with lichen. The bird then lays two eggs, each the size of a coffee bean, inside. Awwww….