can all birds lay eggs

How do birds lay eggs? Most people don’t know it, but all female birds can lay eggs, regardless of whether they have mated with a male.

Think about chickens—they lay all the eggs we buy in supermarkets for us to eat without ever even seeing a rooster. The same is true for a pet bird laying eggs. The difference is that for most parrot species, males and females cannot be distinguished just by looking at them, because parrots do not have external sex organs and males and females only look different in a handful of species.

All About Birds is a free resource

Available for everyone, funded by donors like you

American Kestrel by Blair Dudeck / Macaulay Library Search for species name or keywords

Or Browse Bird Guide by Family or Shape

Need Bird ID Help? Try Merlin

How Do Birds Lay Eggs?

Female birds ovulate (small swellings that burst) on a regular basis from their ovaries, just like women do. They do this independently of males. Female birds do not menstruate, although ovulation causes women to do so. As an alternative, their ova, also known as ovulated follicles, pass through their bodies and emerge as the well-known hard-shelled eggs.

Although wild female birds ovulate year-round, they typically increase their reproductive activity in response to environmental cues, such as longer days and warmer temperatures in the spring, in order to get ready to lay eggs and raise young. Because they are typically not exposed to these variations in light and temperature, pet birds living in our homes may ovulate and lay eggs year-round.

How Does an Egg Develop?

As embryos, birds have two ovaries. With the exception of certain raptor species and Australia’s brown kiwi, most birds regress their right ovary as they mature, leaving only their left ovary to develop.

The developing follicle on the surface of the ovary ruptures to release the egg, or ovum, which then enters the funnel-shaped end of the oviduct, which resembles a woman’s fallopian tube. This tiny bundle of cells travels down the oviduct with a coating of yolk around it, which, should the egg be fertilized, serves as the “food” source for the growing embryo. After that, the membranes inside the egg, the shell, and another layer of albumen, or “white,” are applied to the ovum inside the yolk.

The hard shell, which is the last to be added while the egg is still in the uterus and right before it exits the bird’s body through the cloaca, contains calcium and other minerals. This common chamber of the cloaca is where the reproductive tract, urogenital (reproductive and urinary) tract, and gastrointestinal tract empty.

Through the vent opening, birds transfer their eggs from inside their cloacas to the exterior of their bodies. This is also the exit point for both urine and stool (the white, solid, chalky part of the urine and the clear liquid urine).

For the egg to properly deflate and not become stuck, its pointed end needs to be facing the vent. In the event that it is not, or if the egg is large, birds may experience difficulties laying, become “egg-bound,” and need veterinary assistance in order to lay the egg.

The majority of parrots require up to two days for the egg to exit the ovary, travel through the oviduct, and exit the vent. Therefore, female parrots can typically lay an egg every other day!

FAQ

Which bird Cannot lay eggs?

peacock is a male peafowl and hence it does not lay eggs and does not give birth to baby peacocks. Actually peahen which is female peafowl give birth to baby peacocks by laying eggs.

Can male birds lay eggs?

Single female birds can and often will lay infertile eggs, without needing a male bird. An egg can not be fertilised after it has been laid. Not all eggs are fertile (even if you have both a male and female bird). Boys don’t lay eggs.

Are all bird eggs fertilized?

Some birds lay eggs even when the eggs have not been fertilized; it is not uncommon for pet owners to find their lone bird nesting on a clutch of infertile eggs, which are sometimes called wind-eggs.

Do peacocks lay eggs?

Technically, peacocks do not lay eggs. The word peacock refers to the male bird, while the female is called a peahen. The peahens lay the eggs.