Sunda Golden Oriole?

posted in: Species | 2

“Breeding season is here, and every morning the male Black-naped Oriole calls from the trees outside our fourth floor apartment. Usually it is hidden inside the canopy, but this morning it was out in the open giving stunning views; although I don’t own a camera anymore I couldn’t help myself, I grabbed one of Ng Bee Choo’s and produced this snapshot. Notice how the neck and throat sack balloons up when it calls.

Sunda Golden Oriole? [MortenStrange]

“Where I grew up in northern Europe, the Eurasian Golden Oriole (Oriolus oriolus) was rare and elusive. Here I love seeing the local species, O. chinensis, almost every day, what a stunning bird; the penetrating fluty whistle can be heard everywhere, even in the city. The Black-naped Oriole forms a superspecies with other closely related birds in Europe, Africa and India, the O. chinensis itself occurs in 20 identified subspecies.

Sunda Golden Oriole? [MortenStrange]

“However, exact status and taxonomy in Singapore is not entirely clear. Old literature suggests that we have two subspecies here: O. c. diffusus which is a winter visitor from China and Russia and O. c. maculatus, resident in Malaysia, Singapore and parts of Indonesia (for some reason it is absent from Borneo, apart from a few single records). I have seen the migratory diffusus in Thailand (where maculatus doesn’t occur), and it is strikingly different; it has bright yellow upperparts with just a narrow strip of black in the wing. I have never seen this form in Singapore, has anyone else out there? In fact, I wonder if it even occurs now!?

“Our resident form, maculatus, appears to be a fairly recent invader; 100 years ago it was rare in Singapore. Deforestation and possibly the bird trade from Indonesia enabled it to expand; today it is among our top-10 most numerous birds according to various surveys. With recent taxonomic revisions, the maculatus form has been proposed split into a separate species, Sunda Golden Oriole (O. maculatus); with Dark-throated Oriole (O. xanthonotus) now locally extinct in Singapore, that would then be our one and only beautiful taxon in the Oriolidae family.”

Morten Strange
Singapore
28th February 2018

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2 Responses

  1. Howard Banwell

    I took a photo at my Koh Samui house in 2011 but only on reading this today did I realise it may be of interest to anyone tracking the Black-naped Oriole species.

    From what I have read in various source material, as Morten implies, O.c.diffusus is the non-breeding winter visitor present throughout Thailand, while O.c.maculatus is the resident breeder from Indonesia northwards to Peninsular Malaysia and perhaps the extreme south of Thailand.

    My photo shows an adult male maculatus with an apparently somewhat dependent juvenile. Interest lies in 1) the fact that this subspecies has spread at least as far as Samui (c.600km up into Thailand), and 2) the breeding date which – assuming the juvenile is say 4-weeks old – must have seen mating perhaps in September and hatching late-October, dates outside the commonly reported December to July timeframe (Robson, Wells, HBW).

    When I posted this on the BCST Thai Bird Report Facebook page earlier, I was told that O.c.maculatus has been breeding at least as far north as Bangkok for many years now

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    • Morten Strange

      Hi Howard; thank you for your comment. You are right, my statement ” …Thailand (where maculatus doesn’t occur),” was an over-simplification! Round (1991) has O. chinensis as “common winter visitor, may possibly breed”, Robson (2000) has it as “Uncommon to common resident … extreme south Thailand …”. There indeed seem to be more records lately of the resident form, maculatus, in Thailand. Your personal experience and other comments confirm this. Others may be better experts in this than me, but it could be that maculatus has either been overlooked or is actually expanding northwards out of its original Sunda range. Thank you for pointing this interesting development out. Morten

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