Black-naped Oriole – immature

on 26th March 2018

“The ripe papayas in the neighbourhood are a magnet for Black-naped Orioles (Oriolus chinensis maculatus) and this self-feeding, immature bird was present today at the same time as an adult. Note the immature features:

OrioleBN-imm [AmarSingh]

1. Poorly developed black on tail (above).
2. Incomplete/developing black nape and face mask.
3. The black streaks on the breast (below).
4. The iris is red-brown, rather than fully blood red.

OrioleBN-imm [AmarSingh]
OrioleBN-imm [AmarSingh]

“Of interest is the bluish facial skin, not described in literature. Looking through my older images of juveniles, it is present in some images/birds. I suspect the black mask will obscure this in adults. The bill is like the adult colour, although I have seen immature birds of similar development that still have partially black bills.

OrioleBN-imm [AmarSingh]

“There is still limited data on how juveniles and immatures change. I went through all my past images of young birds and did this composite of 9 different birds based on age/appearance (see above). The top 3 are recently fledged birds. The middle three juveniles that were able to feed self, and the bottom 2 on the left immature birds with one adult on the bottom right. Some observations:

1. The iris changes from grey-brown, to brown, then brown-red to blood-red.
2. The bill is much more variable. Although generally black in juveniles it can have a pink hue; sometimes more pink in younger birds and darker black in older birds. A more mature bird (8th in sequence) can have residual black in bill while a less mature bird can have an all pink bill.
3. Similarly the black nape and eye mask can develop earlier or later.
4. Some have a more prominent hooked bill.”

Dato’ Dr Amar-Singh HSS
Amar-Singh HSS (Dato’ Dr)
Ipoh, Perak, Malaysia
15th February 2018

Location: Ipoh, Perak, Malaysia
Habitat: Urban environment

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.

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