Okapi (Okapia johnstoni) Fact Sheet: Reproduction & Development

• Males enter female home ranges to mate.
• Males approach females unobtrusively and cautiously.
• Spend the day making low, moaning calls
• Males marking with urine occurs most frequently during courtship.
• During courtship, couple stands head to tail in a reverse parallel position, accompanied by circling and mutual sniffing of inguinal areas.
• Males and females flehmen
• Males then go through a series of behaviors including head and neck stretches, head forward and upward positions, erect postures, nose lifting, and leg kicking.
• Receptive female responds by a head-low posture, often with the tail shunted aside.

• Female estrus cycles occur every 15 days throughout the year, but are often irregular.
• Litter size: one (only one record of twinning)

• Gestation lasts around 440 days (14 months).
• Signs in females or impending birth are swelling of the udder, discharge from the vagina and swelling of the udder (swelling of the udder may occur 2 months before the birth).
• Females usually stand during birthing labor, but may recline for brief periods.
• Mother typically ingests the fetal membranes and placenta.
• High frequency of contact and grooming between mother and infant after birth. However, mothers may respond aggressively to the newborn, striking with the head or hooves and sometimes killing the infant.

Infant

• Weight: 14-30 kg (31-66 lb) at birth; weight doubles by end of first month.
• Okapi milk has 1/3 more protein than cow's milk and low fat content.
• "Allosuckling" (infants nursing from multiple females, not solely mother) observed.
• Infants spend about 80% of time at the nest during the first 2 months (this lack of activity may serve to ensure rapid growth).
• Infants start taking solid food by the 3rd week, and rumination can be seen by the 6th week.
• Weaning takes place at 6 months, although young may continue to suckle for > 1 year.
• Horn development doesn't begin until about one year.

Adult

• Adult size reached at about 3 years
• Sexual maturity in managed care reached after 1 year 7 months (female) and 2 years 2 months (male).

Managed care

• Median life expectancy
  • 17 years (male, female data combined) (AZA 2024)

It takes an okapi calf about three years to reach adult size.

Image credit: © San Diego Zoo Wildlife Alliance. All rights reserved.

Bodmer & Rabb (1992)