Feeding of Chocolate Pansy butterfly to Yellow-vented Bulbul chick

“As described in an … LINK earlier post, a pair of yellow-vented bulbuls (Pycnonotus goiavier) built a nest inside a staghorn fern (Platycerium willinckii) in my garden and one chick eventually fledged.

YVB-ChocPansy [NgiamShihTung 1

“During brooding, both parents fed the chick a variety of seeds, berries and insects. The above sequence of images was taken on day 13 after hatching. One of the bulbuls caught a Chocolate Pansy butterfly (Junonia hedonia ida) but instead of taking it to its chick straight away, it flew to a nearby fence and strutted up and down the fence with the butterfly in its beak for about 7 minutes before bringing the prey to its chick (below). I would speculate that the reason for this behaviour was to make sure that the butterfly was dead or incapacitated before feeding it to its chick.

YVB-ChocPansy [NgiamShihTung 2

“Alternatively, was it showing off its catch or performing a territorial display? The bulbul’s mate also joined it on the fence. Throughout the nesting period, both bulbuls were frequently seen perched on the fence, which I thought odd, because the fence is very exposed and they would be vulnerable to predators while out in the open. It is possible that this was a deliberate decoy behaviour to draw attention away from their nest.

OLYMPUS DIGITAL CAMERA
OLYMPUS DIGITAL CAMERA

“As seen in the video below, the adult bird flies to another fern first and looks around for some time before flying to the nest (above). Unfortunately, the butterfly seems to be too big for the chick to swallow, and the parent ends up eating (00:19 and 00:27) a portion if not the whole butterfly! After feeding the chick, the parent remains at the nest for about a minute (perhaps waiting to see if the chick will produce a fecal sac) then leaves. As it turns out, the chick fledges about an hour later (see my previous post LINK) and never returns to the nest again.

Yellow-vented bulbul feeding chick from Shih Tung Ngiam on Vimeo.

Yellow-vented bulbul (Pycnonotus goiavier) feeding a butterfly (Chocolate pansy, Junonia hedonia ida) to its chick.

“At least two Yellow-vented Bulbuls remain in my garden, and both appear to have adult feathers so I assume (or hope) that the fledgling is hiding somewhere else in the vicinity.”

Ngiam Shih Tung
Singapore
6th April 2017

Leave a Reply