The Life History of the Koala
The female usually begins at the age of two or three to mate and produce one offspring per year, while others do not produce annually depending on their age and the suitability of the habitat. Females live up to twelve years, providing five or so progeny to the population on average throughout her life.
The developing marsupial at age 35 days is termed a “joey” as it grows to two centimetres long within the mother’s pouch, typical of marsupials. The joey will move from the birth canal to pouch using its surprisingly well-developed sensory system for direction, then attaching one of the mother’s teats. The teat swells within the joey’s mouth, preventing it from being unintentionally dispatched from its food source. The joey develops for six or so months in the pouch, and begins consuming “pap,” a substance produced by the mother that includes feces with eucalyptus. The mother has an opening on her abdomen to secrete the pap, which the joey accesses by leaning out of the pouch to feed from regularly until it can leave the pouch and feed lying on its mother’s stomach.
The young eventually ride the mother’s back to feed on fresh eucalyptus leaves and suckle the now elongated teat that emerges from her pouch for up to a year or longer, dispersing when the next season’s joey appears. The breeding season of the koala spans August to February, during which males frequently bellow for mates and the previous year’s progeny disperse from their mothers’ care. As a K-selected organism in terms of life history theory, the koala which stays with its mother longer (if she does not produce another joey the following year) is thought to have a better chance of survival due to the increased parental care and protection.
Females tend to live longer than males, who lead a riskier lifestyle involving territorial fights, predation, and poorer habitats. An undisturbed male koala may live roughly ten years, though males living in more urban environments with exposure to human-induced risk factors (traffic, predatory pets) may only live a few years. |
Video about Koala's mating at an Australian Zoo
References:
1. Smith, M (1979) . Notes on Reproduction and Growth in the Koala, Phascolarctos cinereus (Goldfuss). Australian Wildlife Research 6 , 5–12.
http://dx.doi.org/10.1071/WR9790005
2. Rhodes, Jonathan R., Thorsten Wiegand, Clive A. Mcalpine, John Callaghan, Daniel Lunney, Michiala Bowen, and Hugh P. Possingham. "Modeling Species' Distributions to Improve Conservation in Semiurban Landscapes: Koala Case Study." Conservation Biology 20.2 (2006): 449-59. Web.
3. https://www.savethekoala.com/about-koalas/life-cycle-koala
1. Smith, M (1979) . Notes on Reproduction and Growth in the Koala, Phascolarctos cinereus (Goldfuss). Australian Wildlife Research 6 , 5–12.
http://dx.doi.org/10.1071/WR9790005
2. Rhodes, Jonathan R., Thorsten Wiegand, Clive A. Mcalpine, John Callaghan, Daniel Lunney, Michiala Bowen, and Hugh P. Possingham. "Modeling Species' Distributions to Improve Conservation in Semiurban Landscapes: Koala Case Study." Conservation Biology 20.2 (2006): 449-59. Web.
3. https://www.savethekoala.com/about-koalas/life-cycle-koala