2017年3月7日 星期二

The Cyornis Blue

Leaving this blog for more than a year, mainly because of my study. Now, as still during the unemployed period, I have more time and better start again and focusing more on bird ID.

In this Feb and March, two Cyornis species, Chinese Blue Flycatcher Cyornis glaucicomans and Hill Blue Flycatcher Cyornis banyumas were recorded in Hong Kong. I took the chance and manage to get some shots of both. The Chi Blue is quite elusive while the latter one is being fed, allowing me to take photos of reasonable quality.

Male Cyornis is usually in a combination of blue plus yellow and sometime causing problems in identification, while female is duller and much more troublesome. Luckily, the two we have recorded recently are first-winter male, and assuming adult plumage in this time of year.

Chinese Blue Flycatcher, note the brownish wing indicating this is a 1st winter bird

The key feature for separating from Hill Blue is mainly the throat. For Chi Blue, the yellow throat is more limited, showing a very narrow triangle and blue chin.

Chinese Blue Flycatcher

The Hill Blue also showing brownish wing, and pale tips on tertials.
  
Hill Blue Flycatcher
Hill Blue Flycatcher
Hill Blue Flycatcher

 The yellow throat of Hill Blue is wider and showing a yellow chin in most of the angles.

Hill Blue Flycatcher
Hill Blue Flycatcher
A comparison

Although both flycatchers are put on the latest HK checklist cat I, male Cyornis is a common pet species and many of the past records are treated as escaped birds. For the case of Hill Blue, the closest range is Guangxi and mainly non-migratory, under the subspecies whitei. Worn feather especially the tail can be observed in this bird, leaving us a question whether this bird is truly wild or not.

Hill Blue Flycatcher

And according to the recent studies, the Jungle Flycatcher is also grouped into the genus Cyornis, like this Brown-chested Jungle Flycatcher Cyornis brunneatus taken in mainland China few years ago.

Brown-chested Jungle Flycatcher