Egg Laying
Flamingos most often lay one large egg. Eggs range in size from about 78 by 49 mm (3 x 1.9 in.) and 115 g (4 oz.), to 90 by 55 mm (3.5 x 2.1 in.) and 140 g (4.9 oz.).
The egg is oblong in shape, similar to that of a chicken.
The egg is usually chalky white, but may be pale blue immediately after it is laid.
Females have been known to lay two eggs, but this is rare.
Incubation
Incubation begins soon after the egg is laid. The incubation period is between 27 and 31 days.
Both the male and female take turns incubating the egg by sitting on top of the nest mound.
- During incubation, flamingos will stand, stretch their wings, and preen themselves frequently.
- A parent bird carefully lifts and turns the egg with its bill.
Eggs that fall from the nesting mound are not retrieved.
Hatching
Hatching takes between 24 and 36 hours.
The chick calls frequently as it breaks out of the shell.
The chick breaks through the shell using a growth on its bill called an "egg tooth". The egg tooth is not a true tooth and falls off soon after the chick hatches.
Flamingo parents appear anxious while their chick is hatching. They stand, look at the egg, and vocalize.
The adult stands, looks down, and gently preens and nibbles at the emerging chick.
Chick at Hatching
Newly-hatched chicks have gray or white down feathers, a straight red bill, and plump, swollen red or pink legs.
The leg swelling decreases approximately 48 hours after hatching, and the red bill and legs turn black in seven to ten days.
After hatching, a flamingo chick is not very agile. Movement is limited to pushing its wings or lifting its head.
Care of Young
Parents are able to recognize their own chick by sight and vocalizations. They will feed no other chick.
A flamingo chick will leave the nest after four to seven days, when it is strong enough to stand and walk. Parents keep a close, protective watch on their chick as it explores its habitat.
Chicks gather in large groups called creches (French for "crib"). Parents are able to locate their own chicks in the creche at feeding time.
Adults feed their chicks a secretion of the upper digestive tract referred to as "milk". "Milk" secretion is caused by the hormone prolactin, which both the male and female flamingo produce.
- "Milk" is 8% to 9% protein and 15% fat, similar to mammal milk.
- "Milk" is red in color due to the pigment canthaxanthin. Chicks store this pigment in the liver, to be deposited in their adult feathers when they grow.
Chick Development
Flamingo chicks are able to swim before they are typically old enough to leave the nest for good.
Young chicks have been seen imitating feeding methods while standing in shallow water.
Chicks begin to grow their flight feathers after 11 weeks. At the same time, the bill begins to hook, allowing the chick to feed itself.
Chicks lose their juvenile gray or white color gradually over a two or three year period, at which time their pink feathers begin to show.
