Buergers'/Goodfellow's (Dendrolagus goodfellowi) and Matschie's (Dendrolagus matschiei) Tree Kangaroos Fact Sheet: Reproduction & Development

• Information from other species
  • Observations of courtship and mating limited - primarily from Australian tree kangaroos (Martin 2005)
    • Difficult to locate and observe tree kangaroos in dense rainforests of New Guinea
  • Bennett's tree kangaroo (D. bennetianus) - in wild (reviewed in Martin 2005)
    • Observed male sitting in trees with same or different females over series of nights
    • Mating not observed, but pouch young reported 2 months later
  • Lumholtz's tree kangaroo (D. lumholtzi) - most detailed study in managed care (Johnson & Delean 2003)
    • Male investigates females in estrus
      • Approaches female from front, sniffs pouch area
      • Moves to back, sniffs female's cloaca (urogenital opening)
    • Male rubs head, neck, and shoulders on female's cloaca
      • Head, neck, shoulders become covered in cloacal fluids
    • Male engages in mating
      • Male clasps female from behind with forelimbs around her chest
      • Female hindquarters raised, supports weight on her forepaws
      • Female makes soft trumpeting sound and shivering action of head and neck
    • Mating continues for 10-35 m, up to 3 times per day, over 1-3 days
    • Mating usually occurs on the ground
• Matschie's tree kangaroo- observations in managed care (Heath et al. 1990)
  • Courtship
    • Female initiates - drops to ground, approaches male
    • Male engages in tongue-clicking and sniffing female's anogenital region
    • Initially, female growls, hisses, and/or swats at the male
  • Mating
    • If in estrus, female allows male to mount within 10 m
    • Male repeatedly mounts and engages in mating for up to 60 m

Timing of Breeding (Bush & Montali 1999; Flannery et al. 1996; Heath et al. 1990)

• Estrous cycle
  • Polyestrous - may breed any time of year (Heath et al. 1990)
  • Tree kangaroos have estrus cycle lengths of 51-79 days (Bush & Montali 1999)
    • Buergers' tree kangaroo - about 54 days (Flannery et al. 1996)
    • Matschie's tree kangaroo - 59 days (North 2008)
      • Measured by reproductive hormone levels in feces
• No embryonic diapause (Heath et al. 1990; Flannery et al. 1996; Johnson & Delean 2003)
  • Post-partum estrus and embryonic diapause (delayed development) not observed in tree kangaroos
    • Common in ground-dwelling kangaroos and wallabies

• Gestation period
  • Buergers' tree kangaroo - 44 d (Heath et al. 1990)
  • Matschie's tree kangaroo - 45 d (Kingston 1994 as cited by Flannery et al. 1996)
  • Tree kangaroos have longest gestation period of any marsupial (Martin 2005)
    • Reason unknown
    • Next closest: gray kangaroo (Macropus giganteus) at 38 d

• Birth (Flannery et al. 1996; Heath et al. 1990; Thompson 2000)
  • Litter size: normally 1
    • Twin D. g. buergersi documented at San Diego Zoo
  • Weight at birth: undetermined
  • Female assumes birth posture - sits on large horizontal branch with tail between hindlimbs, weight on base of tail
  • Young crawls from birth canal into pouch (takes about 2 min), attaches to 1 of 4 teats
  • After birth, mother cleans pouch thoroughly with tongue
• Infant - Pouch Life (Flannery et al. 1996; Heath et al. 1990; Thompson 2000)
  • Buergers' tree kangaroo
    • First out of pouch - 28-31 wk (7-8 mo)
      • Images and video (Cleveland Metroparks Zoo)
    • Permanently out of pouch - 39 wk (10 mo)
  • Matschie's tree kangaroo
    • Attached to nipple - about 100 d (3 mo)
    • Head out of pouch - about 22 wk (6 mo)
    • First out of pouch - about 28 wk (7 mo)
    • Permanently out of pouch - about 41 wk (10 mo)
• Subadult
  • Weaning age (both species): about 12 months (Wilson and Mittermeier 2015)
    • Follow mother "at foot" for 2-3 mo after permanently leaving pouch
• Adult (Flannery et al. 1996; Thompson 2000)
  • Buergers' tree kangaroo
    • Age of sexual maturity - about 2 years
  • Matschie's tree kangaroo
    • Age of sexual maturity - around 2-2.5 y old in managed care
    • A female may give birth to 10-12 young over her lifetime

Wild populations

• Buergers' tree kangaroo
  • 6–8 years (Moeller 1990)
• Matschie's tree kangaroo
  • 5–8 years (Moeller 1990)

Managed care

• Matschie's tree kangaroo
  • Median life expectancy
    • About 12 years (AZA 2023)

(Martin 2005)

• Common threats to tree kangaroos in New Guinea
• Predation
  • Humans are primary predator
    • Humans use hunting dogs - most tree kangaroos killed by dogs running them down
    • Over-hunting has caused decline or extinction of many tree kangaroo populations
  • Pythons - most too small in New Guinea to threaten tree kangaroos
    • Boelen's python (Morelia boeleni) inhabits montane rainforests above 1,000 m (3,300 ft) and is large enough to take a juvenile tree kangaroo
    • Unconfirmed reports from hunters in Toricelli Mountains that a large python takes tree kangaroos
• Falling out of trees
  • Particularly a problem for young tree kangaroos
• Habitat fragmentation and habitat loss

After birth, tree kangaroo joeys spend about 7 months growing and developing, before first emerging from their mother's pouch.

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

Bush & Montali (1999)
Flannery et al. (1996)
Heath et al. (1990)
Johnson & Delean (2003)
Kingston (1994)
Martin (2005)
Moeller (1990)
North (2008)
Thompson (2000)
ZIMS (2018)