Reproductive behaviour and food consumption associated with the captive breeding of platypus (Ornithorhynchus anatinus)

A female platypus Ornithorhynchus anatinits was intensively monitored with the use of video equipment in captivity at Healesville Sanctuary, Victoria, Australia to record feeding and behavioural changes that occurred as a result of only the second successful raising of young platypus (twins) in captivity. These results revealed the female to be inactive (not leaving the burrow) for periods up to 6 days, and mating occurred 15-21 days before eggs were laid. The nest was built over 5 nights between 5 and 9 days before the eggs were laid. The eggs were thought to have been laid during a 4-day period when the female was confined to her burrow. Once the eggs were laid there was a slow initial rate of feeding which sharply rose 20 days after the eggs were laid. The first time the female spent a day away from the young was 39 days after the eggs were laid, after which she decreasingly nested with them until she spent only 8% of the time with them when they emerged from the burrow, 131 and 136 days after the eggs are thought to have been laid. She rarely went in the nest after day 155, suggesting that the lactation period is c. 135-145 days, assuming 10 days for incubation. The time of emergence also corresponded with the peak in the female's food consumption, which correlates well with the high demands of late lactation, with the daily food intake reaching e. 90-100%, of body weight 140 days after the eggs are thought to have hatched. This captive breeding of the platypus has provided the first records of the gestation period, food consumption in relation to breeding stage, the time the female spends with her young during their development, and a partial growth curve of developing platypus.