14 Extraordinary Bird Egg Facts
Updated: Jan. 12, 2023
Learn interesting egg facts, including what bird lays pink eggs, what bird lays eggs in another bird's nest and why bird eggs aren't round.
Bird Eggs Are Similar to Dinosaur Eggs
One of the most interesting bird egg facts that despite the broad variety in colors and markings displayed by bird eggs, just two pigments are responsible for staining the shells of all known species of living and extinct birds, including dinosaurs.
Learn how to identify bird eggs by color and size.
Cowbirds Are Nest Thieves
Female brown-headed cowbirds deposit their eggs in other birds’ nests. Cowbird eggs have been found in nests of more than 220 other species.
How Strong Are Eggshells?
Large birds sit on eggs, too, so their eggs have to be strong enough to withstand the weight. It takes about 26 pounds of pressure to break a swan egg.
Learn when bluebirds nest and lay eggs.
How Much Does an Ostrich Egg Weigh?
Here’s another one of the most amazing egg facts: a single ostrich egg can weigh as much as 5 pounds. Psst—this is the only bird nesting material you should put out.
What Kind of Bird Lays Dozens of Eggs in a Nest?
A wood duck can lay up to 15 eggs in one nesting attempt, but a single nest may have as many as 40 eggs from more than one female.
Learn how to recognize northern cardinal eggs.
Hummingbird Eggs Are Tiny
Rufous hummingbird eggs are 1/2 inch long and fit snugly in the 2-inch-wide nest, which usually holds two eggs. Here’s everything you need to know about hummingbird nests.
How Long Does Egg Laying Take?
Most songbirds lay one egg per day until their clutch is complete. Learn more about mourning dove eggs and baby mourning doves.
What Bird Lays Pink Eggs?
Pale pink at first, tree swallow eggs turn white within four days. Learn more about swallow nests.
Do Birds Peep Before Hatching?
American white pelicans lay two eggs per clutch. The young are able to squawk from inside their eggs if they’re too hot or cold. Check out super cute photos of baby birds.
Why Are Bird Eggs Not Round?
An egg that is pear-shaped easily settles within the nest, or even on bare ground if the parents opt not to build a nest. Learn about the different kinds of bird nests and how to spot them.
Some Birds Can Recognize Their Own Eggs
Eggshell colors serve to signal the identity of each egg. For example, the parasitic brown-headed cowbird egg sticks out in the nest among an American robin’s blue eggs. Typically, the robin recognizes the cowbird egg and tosses it out.
Discover how orioles weave elaborate nests.
Eggshells Help Baby Birds
The eggshell serves as a calcium supply for the growing embryo. As the embryo matures, the shell slowly becomes thinner and the hatchling has an easier time breaking through.
California Condors Don’t Have Many Eggs
Endangered California condors wait until they’re 6 to 8 years old to find mates, then produce only one egg every one to two years.
Oldest Egg Laying Bird
This last one of our egg facts might be the most amazing! Wisdom, a 70-year-old Laysan albatross and the oldest banded wild bird on Earth, hatched an egg in 2021 with the help of her mate, Akeakamai.
Next, get ready for baby birds with these tips for nesting season.
