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Subject: Is it female Mugimaki flycatcher? [Print This Page]

Author: fatchun Time: 10/09/2010 16:58 Subject: Is it female Mugimaki flycatcher?

TPK 10-9-2010

Sorry for only a few shots provided and I could not see its back as it just appeared with a short time only.

Thank you for your advice.

Author: wgeoff Time: 11/09/2010 09:37

This could be the female Blue-throated although the breast and throat colour is very orange. Mugimaki should have two pale wing-bars which I can't see any sign of on these photos. Also the wings seem rather short for a Mugimaki.

It's very early for a Mugimaki, these don't usually arrive until mid-October.

[ Last edited by wgeoff at 11/09/2010 14:27 ]

Author: Beetle Time: 11/09/2010 17:42

geoff,
i have another individual seen on the same day, it will be great if you can compare both individuals.
http://www.hkbws.org.hk/BBS/viewthread.php?tid=12089

Author: fatchun Time: 11/09/2010 17:50

Quote:

Original posted by wgeoff at 11/09/2010 09:37
This could be the female Blue-throated although the breast and throat colour is very orange. Mugimaki should have two pale wing-bars which I can't see any sign of on these photos. Also the wings seem ...

Thanks geoff. I know there might be some different betwee the real color and the color in the book(Honk Kong and South China Bird guide), but, in my opinion, I think that the female blue-throated flycatcher would have paler throat instead of the same color as the color of the chest.

One point that I missed when ID this bird was the length of wings. Yes, when comparing the length of wings, this bird has shorter wings than the Mugimaki. Thank you very much.

Author: fatchun Time: 11/09/2010 18:10

Quote:

Original posted by Beetle at 11/09/2010 17:42
geoff,
i have another individual seen on the same day, it will be great if you can compare both individuals.
http://www.hkbws.org.hk/BBS/viewthread.php?tid=12089

The photos reflect the same coloration as the real bird. So I think it should have the same / about the same orange color in its throat and chest.

For me, these two birds were quite different. If the bird of my photos is blue-throated, would Beetle's one is other species of bird? Or, this tells us that there might have two or more individual of blue-throated flycatchers in TPK? If yes, it would be a very interesting record for me.=]

Author: wgeoff Time: 11/09/2010 19:33

I think it needs an expert to sort these out, and that's not me.

Without a back view of the first bird (the Mugimaki?), it's difficult to be sure but I don't think it's a Mugimaki. Here are two Mugimakis on OBI and the longer and more pointed wings and pale wing bars can be seen

http://orientalbirdimages.org/birdimages.php?action=birdspecies&Bird_ID=2681&Bird_Image_ID=38832&Bird_Family_ID=216

http://orientalbirdimages.org/birdimages.php?p=5&action=birdspecies&Bird_ID=2681&Bird_Family_ID=216&pagesize=1

and here are two Blue-throated with rather different breast colours

http://orientalbirdimages.org/birdimages.php?p=7&action=birdspecies&Bird_ID=2642&Bird_Family_ID=216&pagesize=1

http://orientalbirdimages.org/birdimages.php?p=10&action=birdspecies&Bird_ID=2642&Bird_Family_ID=216&pagesize=1

Blue-throated has now been split into two species, an eastern form called Chinese Blue and a western form still called Blue-throated. Only the eastern form should appear in HK in the wild. Whilst the males are quite easy to differentiate, I'm not sure that applies to the females although an orange throat (like the first bird by fatchun) should indicate the western form, the eastern form should have a pale throat. The two OBI photos above are both claimed as western. However there are subspecies also as well as first winter birds. Female Blue Flycatchers are clearly very difficult to separate, it needs an expert not me.

The second bird could be a Hainan Blue female but seems rather bright on the back and wings. I'm no expert so we need an expert to comment

[ Last edited by wgeoff at 12/09/2010 12:59 ]

Author: ajohn Time: 13/09/2010 13:37

The taxonomic situation I think is actually even more complicated than Geoff suggests. Blue-throated has been split by IOC (and therefore the Records Committee) into Chinese Blue (C. glaucicomans) and Blue-throated (C. rubeculoides with several subspecies rubeculoides, dialilaema and klossi). Chinese Blue is a long-distance migrant, from China to Malaysia, and is on Category B of the Hong Kong list. Blue-throated is supposedly resident.

Certain recent males in HK have shown some features of subspecies klossi of Blue-throated, including a paler orange breast and narrow extension of orange into the throat. In my opinion, the recent male(s?) at TPK also show these features. I think the RC are still investigating whether this could be caused by a captive diet, and whether there is any age-related variation. According to the literature, klossi is supposedly resident, occurring no closer than southern Vietnam. I don't know what females are like - there is a description in Robson but I can't find any photos.

So it may be necessary to consider three species in assessing these females: Hainan, Chinese and Blue-throated. I think these will be very difficult to assess away from the known ranges. I don't have much experience of female blue flycatchers, and these comments are based on literature not experience. As Geoff mentioned Chinese should show a paler throat, so this bird is probably not Chinese. This bird does seem to have a strong orange colour to the breast, which may suggest Blue-thoated, but that may also be related to age or light conditions. Robson suggests Blue-throated tends to show a stronger buffy eye-ring and paler lores; again this bird may fit. So, there are features suggesting Blue-throated but I'm not sure whether Hainan can be fully ruled out. Not Mugimaki though.

Author: fatchun Time: 13/09/2010 17:07

Thanks for detailed discussion by Geoff and John! I think female blue flycatcher in most case are difficult to be correctly identified. Or I should say no definite answer for the ID of such female blue flycatchers. This may be due to the complicated situation of the distribution of them in HK. Some, most probably blue-throated, are captive, some are true migrants, and some are unknown situation.

I have learnt more through this detailed discussion and information provided. Again, thank you very much.

Chun

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