Hamadryas Baboon (Papio hamadryas) Fact Sheet: Reproduction & Development

Location and timing (Kummer 1968b)

• Mate near sleeping cliffs
• Typically in morning or evening

Mate selection (Kummer 1968b)

• Adult males only court females within their One-male-unit (OMU)
• Females may court and copulate with subadult and juvenile males as well as their unit leader
• Initiated by either sex
• Females present vaginal swelling
• Males may touch female swelling or grasp her hair

Copulation (Kummer 1968b)

• Series of mountings at regular intervals (3-8 minutes in duration)
• Followed by intensive grooming by each partner

Gestation

• c. 170-173 days (c. 6 months) (Kummer 1995; Nowak 1999)

Birth

• Most frequently at night (Abegglen and Abegglen1976; Kummer 1995)

Single offspring (Kummer 1968b)

• Weighing 600-900 g (1.3-2 lb) (Nowak 1999)

Infant (< 2 old) (summarized from Sigg et al. 1982; Kummer 1968b unless otherwise noted)

• Hold to hair of mother for first three weeks (Kummer 1968b)
• Two age classes (some overlap)
  • Black infants: age estimated 0-0.7 years; maximum age of 1 year
    • Hair completely or partially black; face and anal field pink; round head with short snout
  • Brown infants: age estimated 0.7-1.3 years; maximum of 1.5 years
    • Hair brown; round head with short snout; sitting height 25 cm
    • Rarely carried by mother; never by adult males
    • Some infants younger than 0.7 years are in this category based on their physical appearance
• c. 1-2.5 kg by 1 year of age (from Fig. 2 Sigg et al. 1982)
• Weaned just over 1 year of age (Kummer 1968b; Kummer 1995)
• Infanticide observed following changes in leadership within OMU's (Swedell and Tesfaye 2003)
  • New male leader kills offspring of deposed leader

Juvenile and Subadult (from Sigg et al. 1982 unless otherwise noted)

• Males: 2-10 years old
• Leave OMU around 2 years of age
  • Form loose associations with several groups within their band (clan) before attempting to form their own OMU
    • Several years
  • Return to natal clan as adults is typical
• Characteristic male mantle hair begins to develop and is complete (or nearly so) in subadults
• Females: 2-5 years old
• Leave natal OMU between 1.5 and 3 years of age (Sigg et al. 1982; Hapke et al. 2001)

Adult (from Sigg et al. 1982)

• Males
• Sexual maturity (testes descend): 4.8-6.8 years of age
• Aquire first female mate: 8.5- 11 years of age
• Age at first reproduction: 9.5-13 years of age, dependent on social standing
• Females
• Sexual maturity (marked by first estrus): 4-5 years of age
• Age at first reproduction: 5.5-7 years of age, average 6.1 years
• Interbirth interval (IBI): 18-36 months, average 24 months (should previous offspring survive)
• Onset of menopause observed once in a wild population
  • This female survived for approximately 1.5 years after

Managed care

• Median life expectancy
  • 25.7 years (AZA 2023)

Potential predators in Africa (Kummer 1968b, Zinner et al. 2001):

• Lion (Panthera leo)
• Leopard (Panthera pardus)
• Spotted hyena (Crocuta crocuta)
• Striped hyena (Hyaena hyaena)
• Verreaux's eagle (Aquila verreauxii)
• Jackals (Canis mesomelas & C. aureus)
• Cheetah (Acinonyx jubatus)

Potential predators in Arabia (Biquand et al. 1992):

• Wolf (Canis lupus arabs)
• Stripped hyena
• Leopard (Panthera pardus nimr, though it is nearly extinct)

Humans and domestic dogs (Kummer 1995; Biquand et al. 1992)

• Baboons viewed as agricultural pests

Hamadryas baboons of different ages.

Image credit: © Ruben Undheim at Flickr. Some rights reserved.

Abegglen and Abegglen (1976)
Biquand et al. (1992)
Hapke et al. (2001)
Kummer (1968b)
Kummer (1995)
Nowak (1999)
Sigg et al. (1982)
Swedell and Tesfaye (2003)
Zinner et al. (2001)