1. Brown-headed cowbirds deposit their eggs in other birds’ nests. Cowbird eggs have been found in nests of more than 220 other species.
2. 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.
3. A single ostrich egg can weigh as much as 5 pounds.
4. 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.
5. Rufous hummingbird eggs are 1/2 inch long and fit snugly in the 2-inch-wide nest, which usually holds two eggs.
6. Most songbirds lay one egg per day until their clutch is complete.
7. Pale pink at first, tree swallow eggs turn white within four days.
8. 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.