Subadult Large Hawk Cuckoo*

posted in: Morphology-Develop., Species | 3

On the afternoon of 13th January 2010, Arthur Voo spotted and photographed a cuckoo perched on a branch (ca. 7 m above ground), outside the Central Nature Reserve (National Parks Board) office. This was referred to Dr Leong Tzi Ming, who after some deliberation and comparison, suspected that it might be an immature/subadult Large Hawk Cuckoo (Hierococcyx sparverioides). This was subsequently sent to Subaraj Rajathurai for verification.

“I concur with your identification. It appears to be a sub-adult H.sparverioides,” wrote Subaraj. They are uncommon migrants to Singapore and December/January seem good months for an encounter. Distinct features include the white moustache and tail tip, the broad black sub-terminal band with a thin black band above it, the chestnut sides of neck and the bold streaking on throat to upper breast. The short tail may be due to moulting and it still retains the chestnut barring above of its juvenile plumage.”

*Albert Low has written… “It has come to my attention that with regard to the … blog post, it seems highly likely that the bird in question has been mis-identified as a Large Hawk-Cuckoo and should be more correctly considered an individual of the confusing Hodgson’s Hawk-cuckoo complex which is difficult to differentiate in the field… – please see full text under comment.

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3 Responses

  1. This note on the ID of the cuckoo by Albert Low was sent in earlier. We are archiving it for the record.

    “It has come to my attention that with regard to the below blog post, it seems highly likely that the bird in question has been mis-identified as a Large Hawk-Cuckoo and should be more correctly considered an individual of the confusing Hodgson’s Hawk-cuckoo complex which is difficult to differentiate in the field.

    With all due respect to Subaraj, the diagnostic features referred to in the accompanying text appear to be focused a tad too much on the tail section of the bird, which to my knowledge is not a particularly reliable way of differentiating Hawk-cuckoos in the field, particularly in the case of this bird where shortness may indicate some sort of damage or moulting as mentioned within the text.

    Far more telling about the ID of this cuckoo in question is the absence and presence of 3 main features depicted in the photograph. All plumages of Large Hawk-Cuckoo show either an extensive dark area on the chin. The lack of this feature is particularly evident when the bird tilted its head towards the photographer showing off a whitish chin. In addition, this individual shows extensive white patches on the tertials, a feature consistent with the Hodgson’s complex which either have white fringes on the tertials or tertials barred white. The presence of white spots on the nape is the 3rd feature on this bird which is not present in any illustrations,photographs or wild specimens of Large Hawk-Cuckoo that I have seen to date.

    The picture has been sent out to both academics and experienced birders and so far the consensus is unanimous in support of the Hodgson’s Hawk-cuckoo complex. Among the supporters are close friend Yong Ding Li, who wrote an excellent article on this confusing complex for Singapore Avifauna, and Mr Clive Mann, an ornithologist currently working on Old World cuckoos as part of an ongoing project. I personally find it very hard, if not impossible to convince myself that the bird is a subadult Large Hawk-cuckoo as claimed.

    For references, Ding Li’s article can be found at http://wildbirdsingapore.nss.org.sg /SINAV_Vol_22_No_1_Jan_08%20.pdf. There are also photographs of subadult Large Hawk-cuckoos such as the one at http://orientalbirdimages.org/search.php?action=searchresult&Bird_ID=456&Bird_Image_ID=17452&Bird_Family_ID=&p=12 for comparison. Readers may wish to check out other photographic entries under Malaysian Hawk Cuckoo and Hodgson’s Hawk-Cuckoo to gain an understanding of the difficulty of separating them in the field. While I personally would be tempted to call it a Hodgson’s Hawk due to the tertials appearing to be white with barrings as opposed to white-fringed, I will allow readers to draw their own conclusions from the references provided. I am, however, convinced that the bird is not a Large Hawk-cuckoo and would recommend that unless other sources provide compelling evidence to support that claim that the post be modified accordingly.”

    R Subaraj has responded to Albert thus: “Firstly, my apologies, if a mistake has been made on my part. I should have spent and will spend more time looking carefully at the photos. Thank you for bringing this up. With all the constant splitting that has been going on, it is good to highlight the identification criteria from time to time.”

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  2. You are right! Phil Round just confirmed it to be a 1st year Hodgson’s

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  3. […] views of the intricate network of water that fuels the ever-changing ecosystems of this lush …Bird Ecology Study Group Subadult Large Hawk Cuckoo*Name (required) Mail (will not be published) (required) Website. XHTML: You can use these tags: […]

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