Capybaras (Hydrochoerus spp.) Fact Sheet: Reproduction & Development

• In mating season, dominant males conspicuously guard females
• When female in estrus, dominant male sniffs her frequently
• Female whistles when in estrus to attract males
• Female pursued by male enters water and swims back and forth
• Pair mates in water; female often submerged for brief copulation
• Females not wanting to mate may dive deep enough to dislodge male
• Mating pair often interrupted by a second male

• Mating season year round with peak at beginning of wet season
• Female estrus cycle: every 7.5 days; remain receptive only 8 hours
• One litter per year; two litters possible under good conditions
• Harem-based polygynous breeding (one dominant male, several females)
• Life span of male's sperm longer than that in most rodents; capybara mating system promotes sperm competition
• Group association essential for raising young; groups smaller than four adults fail to rear any young

 Gestation

• 150 days
  

Birth

• 4 to 5 pups most common; a breeding group may have 15 pups or more at one time
• At birth young weigh about 1,500 grams (3.3 lbs)
• At birth, all cheek teeth already erupted, with signs of wear (Kramarz 2002)

Infant (< 1 year old)

• Young can follow mother and eat grass shortly after being born (are precocial)
• Young nurse about 16 weeks
• Young may suckle indiscriminately from several females;
• Small groups of young move about herd, nudging females until one stands to allow nursing
• Very young ride on females' backs
• Very young avoid water where caiman and anaconda lurk
• Females spend a lot of time caring for young of different ages

Juvenile

•  Yearlings disperse from parents' group

Subadult

•  By 18 months, weigh about 40 kg (88 lb.)

Adult

• Females sexually mature age 7 to 12 months
• Males between 15 and 24 months

Wild populations

• 7–10 years

Managed care

• Median life expectancy (AZA 2023)
  • Males: 7.1 years
  • Females: 8.6 years

• Preyed upon by foxes, bush dogs, feral dogs, ocelots, cayman, jaguars, eagles, caracaras, black vultures and human hunters
• Wild capybara, especially in Venezuela, are poached and illegally hunted more intensely in the weeks before Easter, when they are a sanctioned by the Catholic Church as a substitute for fish (because of their semi-aquatic habits).
• Jaguars prey most often on young males at the periphery of the group (and furthest from the water)

A one-day old capybara, weighing only 3 to 5 pounds.

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

Macdonald and Herrera (2001)
Nogueira et al (1999)
Ojasti. (1968)
Paula et al (1999)
Rowlands and Weir (1974)
Weigl (2005)