The ostrich is the world’s largest bird and produces the largest egg of any living species. Weighing up to three pounds and measuring about six inches long, the scale of the ostrich egg-laying process is unique. This reproductive feat requires significant physiological investment from the female, known as the hen.
The Duration of the Physical Laying Event
The physical act of the ostrich hen expelling the massive egg is a remarkably quick process given the size of the object. The actual laying event, or oviposition, is generally rapid. The hen typically deposits the egg in the shallow nest bowl within just a few minutes. This rapid expulsion minimizes the hen’s vulnerability to predators while she is stationary.
The Ostrich Egg-Laying Cycle
Once the hen begins her reproductive cycle during the breeding season, the frequency of laying is governed by the time needed to generate the next egg. The production of the yolk, albumen, and the thick shell requires a roughly 48-hour cycle. An actively laying female will deposit one egg every other day. This sustained cycle lasts until the hen has accumulated a full clutch of eggs in the nest.
Clutch Size and Seasonal Production
The ostrich breeding season typically begins in the spring and continues until early autumn. A single hen will lay a clutch that usually consists of 10 to 15 eggs before she begins incubation. In the wild, nests often become communal “dump nests” where several females contribute their eggs. These communal nests can accumulate 15 to 60 eggs, with the dominant hen ensuring her own eggs are positioned centrally for optimal warmth.
Seasonal production is much higher in commercial farming. If the eggs are consistently removed daily or every other day, the hen is stimulated to continue laying. This process, known as “continual laying,” results in a hen producing 40 to 60 eggs or more over a single season. This high output is a response to the hen’s instinct to replace eggs she believes are lost.
Post-Laying: Incubation and Hatching
After the hen completes her clutch, the long incubation period begins. Ostrich eggs require 42 to 46 days before the chicks hatch. This period is shared between the sexes: the drab-colored female sits on the eggs during the day to blend with the sandy terrain. The male, who has black plumage, takes over incubation duties at night, offering superior camouflage against the dark landscape. Due to the egg’s thick shell, the process of hatching is an arduous physical challenge that can take many hours to complete.