To swallow and regurgitate? Not the Yellow-vented Bulbul!

on 9th February 2006

My Alexandra palms (Archontophoenix alexandrae) are fruiting again. The large bunches of red fruits invariable attract Asian Glossy Starlings (Aplonis panayensis) that are a delight to watch, what with their iridescent dark plumage and bright red eyes. I was pleasantly surprised to observe earlier that these birds swallowed the fruits whole but soon regurgitate the seeds after the pulp had been removed in the gut.

Reviewing my earlier images of koels caught in the act of raiding these fruits, I found that I have evidence that Asian Koels (Eudynamys scolopacea) regularly swallow the fruits (see above) but have yet to actually see them regurgitate the seeds.

Yellow-vented Bulbuls (Pycnonotus goiavier) are similarly attracted to these fruits, but only when the starlings are not around. But these bulbuls apparently have a smaller gape than the above two birds as they are not able to swallow the nearly rounded 10×12 mm fruits. Instead, they peck on the red fruits to remove pieces of the soft outer covering, leaving the fruits with patches exposing the seed surface still attached to the bunch.

Obviously the starling, koel and bulbul are inefficient seed dispersers as far as the Alexandra palm is concerned. Depositing the seeds at the base of the parent palm is not advantageous to the plant at all.

I wonder whether there are any animals that actually disperse these seeds. As an exotic palm introduced from the warmer regions of Eastern Australia, it is very possible that the seed dispersers are absent in Singapore.

YC Wee
Singapore
9th February 2006

Comment by R. Subaraj: It would be interesting to find out if some of our local animals like plantain squirrels, actually help disperse the large seeds of some of our exotic palms.

If you like this post please tap on the Like button at the left bottom of page. Any views and opinions expressed in this article are solely those of the authors/contributors, and are not endorsed by the Lee Kong Chian Natural History Museum (LKCNHM, NUS) or its affiliated institutions. Readers are encouraged to use their discretion before making any decisions or judgements based on the information presented.

YC Wee

Dr Wee played a significant role as a green advocate in Singapore through his extensive involvement in various organizations and committees: as Secretary and Chairman for the Malayan Nature Society (Singapore Branch), and with the Nature Society (Singapore) as founding President (1978-1995). He has also served in the Nature Reserve Board (1987-1989), Nature Reserves Committee (1990-1996), National Council on the Environment/Singapore Environment Council (1992-1996), Work-Group on Nature Conservation (1992) and Inter-Varsity Council on the Environment (1995-1997). He is Patron of the Singapore Gardening Society and was appointed Honorary Museum Associate of the Lee Kong Chian Natural History Museum (LKCNHM) in 2012. In 2005, Dr Wee started the Bird Ecology Study Group. With more than 6,000 entries, the website has become a valuable resource consulted by students, birdwatchers and researchers locally and internationally. The views and opinions expressed in this article are his own, and do not represent those of LKCNHM, the National University of Singapore or its affiliated institutions.

Other posts by YC Wee

5 responses

  1. Yes, I have seen this before. However, yellow-vented bulbul will be able to swallow other smaller fruits / berries. A week ago, I sighted the yellow-vented bulbul feeding on Osmoxylon berries.

  2. I found a injured Koel in the ground
    and a large group of crows was hitting
    her. I saved her and took her to doctor.
    Now am feeding her with red cherries.
    Please suggest what fruits, vegetables and
    Nut I can feed her.

  3. I found a injured Koel in the ground
    and a large group of crows was hitting
    her. I saved her and took her to doctor.
    Now am feeding her with red cherries.
    Please suggest what fruits, vegetables and
    Nuts I can feed her.

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