There is a significant positive correlation between a peafowl’s train and its mating success. This correlation is due to female’s preference for more elaborate trains on their mates. Males spend a great deal of energy to produce and maintain good tail conditions, resulting in a trade-off between a longer train and avoiding predators or searching for food. Mating success is usually more successful for the males with the highest number of eyespots (also called ocelli) on their train. If eyespots were experimentally removed from a male’s train below the the range of other individuals eyespot numbers, mating success decreased significantly. There is also a positive correlation between the number of eyespots, the amount of time a male displays to a female during the breeding season, and the overall health of the individual. A peacock that displays less often and has less eyespots has more heterophils circulating in its body, indicating the peacock is spending more energy to fight off an infection than a male that displays more often with more eyespots. Peahens choose the peacocks with the most eyespots because her chicks will hopefully inherit the male’s superior immune system and have a greater chance at survival.
However, females rely on more than one trait when picking a male. Feather ornaments, such as length and number of eyespots during breeding season, is a fixed characteristic based on genetics and can reflect their past condition such as attacks or illnesses. Behavioral displays are flexible characteristics that can change day to day, mate to mate, and improve with experience. For example, peacocks use the sun at different angles when performing visual displays such as “train-rattling” or “wing-shaking”. Visual genetic traits and behavior of the male allow the peahen to determine the health of a mate and the benefits it would confer to their offspring.
Peahens are also very aggressive when it comes to finding a suitable partner. The bigger and stronger females will fight away other females and try to monopolize the male by repeatedly mating with him. Favored males tend to mate with more females and the same female more than once, increasing their fitness significantly. On average, males usually mate with up to six different peahens every breeding season. Because the male only contributes its sperm, females must pick the best possible choice and try to limit the access of other females to increase their own offspring’s survival rates.
Mating System: polygynous
This species becomes sexually mature at three years, though some males can breed at age 2. Females will lay 3-5 brownish oval eggs, but in some cases have laid up to 12. The eggs are laid one at a time every other day. Their glossy shells have deep, small pores that let in water to keep it moist. The incubation period lasts up to 28 days.
The nest is made up of dry sticks and leaves, and is located on the ground, under shrubs. Naturally, a peahen will only lay one clutch per breeding season. If raised in captivity and a clutch is taken away from the female, she will mate again and can lay up to three clutches in a breeding season. The clutches removed from the mother can be given to a foster parent such as a turkey hen.
Chicks are mobile and fully feathered at hatching, can fly in about one week, and rely on their mother for only an additional few weeks. Although the chicks are fairly resilient, they do need relatively warm temperatures to survive and can die in colder climates. Some aviculturists have avoided this problem by raising eggs in incubators. Peachicks must be taught to eat and drink through imitation. Males and females look alike until the males develop their train and bright feathers. It takes up to three years for males to develop a full train. It is almost impossible to tell the difference until a couple of months after hatching in which the males have longer legs. Also, the males will have light gray outer primary feathers and their female counterparts will be brown.
Breeding interval: Indian blue peafowl breed once per year, and more often if clutch is lost.
Breeding season: Indian blue peafowl breed from April to September.
Range eggs per season: 3 to 12.
Average eggs per season: 5.
Range time to hatching: 27 to 29 days.
Range fledging age: 1 to 2 weeks.
Average fledging age: 1 weeks.
Range time to independence: 7 to 10 weeks.
Average time to independence: 8 weeks.
Range age at sexual or reproductive maturity (female): 1 to 3 years.
Average age at sexual or reproductive maturity (female): 3 years.
Range age at sexual or reproductive maturity (male): 2 to 3 years.
Average age at sexual or reproductive maturity (male): 3 years.
Key Reproductive Features: seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate)
Only the females are involved in the incubating of the eggs and the rearing of the chicks. Chicks are mobile and fully feathered at hatching, can fly in about one week, and rely on their mother for only an additional few weeks. If the female mates with a favored male, they usually have larger eggs with a higher amount of testosterone deposited in the yolk. Chicks of males who have the largest or most eye-spots tend to grow faster and have a better survival rate.
Parental Investment: precocial ; female parental care ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female); pre-independence (Provisioning: Female, Protecting: Female)
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