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Black Rhinoceros (Diceros bicornis) Fact Sheet: Reproduction & Development


Characteristic courtship behaviors

  • Spraying
  • Cocking the tail
    • Females perform behavior when sexually aroused
    • Tail lifts and is cocked at an angle
  • Making flehman
    • Males primarily exhibit this behavior
    • Similar to behavior in many other ungulate groups
    • See Olfaction/scent marking
  • Dung scraping
    • Females behavior
    • Scrapes dung pile more energetically
      • Increases in scraping frequency and forcefulness
  • Male follows estrus female for long distances
    • Effort an attempt to be accepted as a mating partner
    • Approach and following behavior
      • May follow calmly
      • Approachs with stiff, dragging legs
      • Exhibits "bluff and bluster" display
        • Male and female face each other nudging heads and jousting with horns
        • Not done with great force


  • Duration
    • Lasts for half an hour or more




  • Males and females mate with more than one individual
    • Partnering can last from one mating session, to days, weeks, or sometimes months
  • Males do not defend harems of females
    • Males do defend a receptive female by charging a potential competitor

Year-round reproduction

  • No discreet breeding season


  • Duration
    • Lasts three days
    • Cycles every 25-30 days
  • It can be difficult to tell when a female is in season
    • Changes in behavior provide clues
  • It is also difficult to tell when a female is pregnant
    • May only become apparent few days before she gives birth

Gestation and parturition

  • Gestation
    • 15-17 months, in the wild
    • 15-18 months, in managed care
  • Age at first parturition
    • 3.5 to 5.7 years old
    • Varies group to group
    • Dependent on density and resource availability

Interbirth Interval

  • Duration
    • 2.5 to 4 years

Life Stages


  • Litter size
    • 1 infant
  • Birth weight
    • 27 - 45 kg (59.5-99.2 lb)

Infant (< 1 year old)

  • Development
    • Begin solid foods in 7-10 days of birth
      • Nibble on grass and small, non-woody plants


  • Independent of mother at 2.5 to 3 years old
    • Birth of new calf results in mother's rejection of the older sibling
    • May find a non-related adult to join after being rejected


  • Sexual maturity
    • Reports of sexual maturity vary widely
    • Females
      • 3.5 to 4 years (Schenkel & Schenkel-Hulliger 1969)
        • May conceive as young as 3.8 years (Estes 1991).
      • Up to 7 years
    • Males
      • 6 years
      • Fully grown at 8 to 10 years (Schenkel & Schenkel-Hulliger 1969)
      • Up to 0 years (Estes 1991).

Typical Life Expectancy

Managed care

  • Diceros bicornis michaeli
    • Median life expectancy
      • 19 years (AZA 2023)



  • Drought
    • Somewhat vulnerable
      • Survive better than many species
    • New mothers and their calves are the most vulnerable
      • Due to reduction in availability of nutritious food
    • Pregnant females often abort their fetuses
  • Malnutrition
    • Kills an animal directly or  makes it more vulnerable to parasites and disease


  • Uncommon cause of mortality
    • Predators typically target sick or young individuals
  • Potential predators
    • Lion and hyena
      • Attacks are rare

Exploitation by humans

  • Primary cause of rhino death
  • Poaching
    • Highly vulnerable to hunting
      • Black rhinos tend to revisit the same resting spots during the day

Year-round Reproduction

Black Rhino and calf

East African black rhino & calf at the San Diego Zoo.

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



Black Rhino calf

Baby African black rhino born at the San Diego Zoo Safari Park in 2010.

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

Page Citations

Bertschinger (1995)
Estes (1991)
Goddard (1966 & 1967)
Hillman-Smith & Groves (1994)
Merz (1991)
Rookmaaker (1998)
Schenkel & Schenkel-Hulliger (1969)

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