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        Discussion Area 討論區 >> Birding Reports & Tips 觀鳥報告及心得 >>  Warblers at Long Valley
        
(Message started by: Mike Kilburn on Oct 20^th, 2003, 7:37pm)

Title: Warblers at Long Valley
Post by Mike Kilburn on Oct 20^th, 2003, 7:37pm

Ths morning Long Valley was full of warblers along with some other migrants and winter visitors.  Almost all the birds were towards the northen corner.

Dusky Warbler - 25 (minimum)
Yellow-streaked Warbler - 1
Black-browed Reed Warbler - 3
Oriental Reed Warbler - 5
Pallas' Grasshopper Warbler - 2
Lanceolated Warbler - 1
Fantail Warbler (Zitting Cisticola)
+ both prinias

Yellow-breasted Bunting - 14
Little Bunting - 2
Eurasian Skylark - 1

+ one escaped Mongolian Lark

Mike

Title: Re: Warblers at Long Valley
Post by Gary on Oct 21^st, 2003, 5:12pm

So many good warblers in Long Valley!
How did you find the Yellow-streaked Warbler. How can it be distingusihed from Dusky Warbler? Is it just by color?

Gary

Title: Re: Warblers at Long Valley
Post by Mike Kilburn on Oct 21^st, 2003, 6:38pm

Iwas a little scared that someone would ask that question!

The answer is that it is not too difficult to separate from Dusky Warbler, but much more difficult to separate from Radde's Warbler.

The best place to look for the answer is the 1994 Hong Kong Bird Report. There are 2 articles by Paul Leader on the identification of Dusky, Yellow-streaked and Radde's Warbler.

The most important step is to be familiar with Dusky Warbler. This species can show a lot of variation as can be seen from the very interesting set of photos taken at Long Valley one or two days ago. with 25+ Dusky Warblers at Long Valley yesterday that is a lot of variation!

You are right that the colour is a good starting point. Dusky is dark dusky-brown with a greyish tinge, while Yellow-streaked and Radde's are both more olive-green in colour.

the next featuresw to compare are the bill and legs - dusky has the darkest legs, while Radde's and YS Warbler have brighter, more orangey legs. However Raddes has rather obvious thick legs compared to Dusky. Yellow-streaked has thinner legs closer to Dusky than Radde's.

The bill of Radde's is very strong and deep from top to bottom, Dusky is fine and pointed. YS is somehwere between the two. The bird yesterday had a bill that look short and wide but not deep. Also it did not show a curved upper mandible, which is a good feature for Radde's

Warning: Both Rade's and YS can show lots of yellow on the underparts, and the streaked of YS are only visible with excellent close views.

Perhaps the most useful feature of all is the call;

Dusky has a harsh "Tack" , which can be repreated several times.
Radde's sounds similar, but softer, while YS has a bunting like "zic", which can also be repeated.

I heard this call but did not see the bird make it.

Hope this helps. Appreciate any correction from the experts
Mike