An earlier post established that the Javan Myna (Acridotheres javanicus) needs 25 days to be with its parents after fledging in order to learn how to fend for itself. This is termed the fledgling period by Erritzoe et al. (2007).
There was another opportunity to confirm the fledgling period of the Javan Myna when on 6th January 2019, a pair of adults walked through my garden with a noisy fledgling tagging along. The latter was begging loudly all the time while the adults were feeding themselves, only occasionally passing food to the noisy fledgling.
The begging cries continued for the next week or so. Initially both adults accompanied the fledgling. Then only one adult was around. And whenever there was an opportunity, this adult left the fledgling to forage alone. When alone the fledgling was able to feed itself, as seen when it was at the compost heap (video below). It had no problems picking from discarded papaya peels and watermelon rind, spending nearly half an hour there. At times it’s begging cries were heard briefly.
At one point an unfamiliar adult arrived at the compost pile. The fledgling flew off but returned to cautiously feed nearby. When the adult flew off, the fledgling continued feeding. When one of the familiar adults arrived, the fledgling flew off to join it and started begging for food.
The total number of days the fledgling remained with the adults was 21. On the next few days the ex-fledgling, now a full fledged juvenile, was seen foraging alone in the garden. No begging cries were heard.
YC Wee
Singapore
27th January 2019
Reference:
Erritzoe, J., K. Kampp, K. Winker & C. B. Frith, 2007. The ornithologist’s dictionary. Lynx Edicions, Barcelona. 290 pp.
