cjacky

Date : 9-MAR-2009
Location : MP

第一次去搵金腰燕 , tick到啦. 再睇書時先發現有另一種叫班腰燕既燕子.

書上說班腰燕和金腰燕很相似, 而班腰燕的頸後沒有完整的偏紅項蔕. hmmmmmmmm 個腦即刻hang 左. 唔識分.


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再係internet search 一下, 台灣果邊. mlchiang 有說:
兩者分辨重點不在栗色頸圈的連續否。而在於體型大小與胸腹紋粗細，多寡。與栗腰帶的色澤深淺。其間亞成鳥的色澤又有些變化，會混淆辨識。我也是看過標本才知前述頸圈的差異是錯誤的描述
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好像有點明白. 不過現時還沒機會親眼比較過. 現在還不會分. . . . .

當天見到既燕子有以下特徵
1. 頸後沒有完整的偏紅項蔕
2. 腰間有條紋
3. 翼底比較白色.
4. 身上條紋是粗還是幼?

msamuel

I share the same puzzle with cjacky.

The following are the photos I took at Xianghai, China on 03May2009:






I originally thought they are Striated Swallow.  But if not having a complete orange band on nape is not instrumental in differentiating a Striated Swallow from Red-rumped Swallow, can any expert out there help to identify which are which, or they are the same kind?

I notice that Striated Swallow is not listed in any category on the "Non-rare Species Report Form".  Would it be possibly that there may be one or two that were overlooked / mis-identified as Red-rumped Swallow?

[ Last edited by msamuel at 1/07/2009 14:52 ]

Sze

Have asked Geoff! And Thank you very much for his teaching again !
His reply is as the follows. Share with all of you!

" I can only look in the textbooks - Field Guide to the Birds of South-east Asia by Robson or Birds of East Asia by Brazil are the best.

Both textbooksn suggest that Striated Swallow has much less red/orange around the rear of the head (the nape) than Red-rumped. There are some other differences like slightly larger size and heavier streaking on the underparts for Striated but these are relative and not easy to observe.

From the photos, all these birds show quite extensive orange/red around the back of the head and should therefore be Red-rumped rather than Striated. Also they don't appear to be heavily streaked on the underparts so no other reason to think they may be Striated.

Best regards
Geoff "

wgeoff

But looking at the photos claimed for Striated Swallow on the OBC website, I'm not sure it's as easy as the textbooks suggest.

Maybe someone who has seen both species would like to comment.

msamuel

The photo below shows more clearly the color on the nape.


Thank you for the interest in this discussion and the responses.  Any further comments are most welcome.

lpaul

Geoff, I think some of the photos on OBI are incorrectly identfied.  I hate to say it, but these include photos from a certain John and Jemi Holmes!!

The id of the two is difficult because there is so much racial variation within the two species, so much in fact that it seems likely that they both represent more than one species.

I find a quick method to separate the two is the shape of the streaks below.  On Red-rumped thay are narrow and even in width, in Striated they are slightly thicker, but usually flare towrds the base of the streak.  However, I've not seen this published so I'm not too sure how reliable this is!

Paul

Sze

Geoff and Paul!Thank you very much for your teaching and sharing!
We have learnt more again! Thanks a lot!

John Holmes

Thanks to Paul Leader for his comments about the Striated Swallow photos on the OBI website.

We have pulled our reference books out again : "A field guide to the birds of South East Asia" (Robson), "Birds of East Asia" (Brazil),  "Swallows and Martins of the World" ( Turner & Rose) and "Handbook of the birds of the World" - Volume 9.

In HBW Vol.9, plate 68 by Hilary Burn shows six races of Red-rumped Swallow - including two streaked races - daurica (lightly streaked) and japonica (more heavily streaked).  For Striated Swallow there are three illustrated races, vernayi (streaked but very rufous), striolata (lightly streaked) and stanfordi (more heavily streaked).

The illustrations (but not mentioned in the HBW text) support Paul's point about Striated Swallow streaks being heavier than the streaks of Red-rumped Swallow and flareing (getting wider) near the base of the streak.

The extent of rufous hindcollar markings does not seem to be as reliable as we'd thought and we're no longer confident that our OBI "Striated" Swallows - taken in SW Yunnan - are properly identified.  To avoid  confusion we shall amend identifications or remove them from the OBI website.

From a Hong Kong point-of-view it is interesting that the striolata race (see HBW etc.) of Striated Swallow occurs in both Taiwan and the Philippines.

"The Birds of HK and south China" (Viney, LAM and Phillipps) anticipates the possibility that Striated Swallow (and, for that matter, Pacific Swallow) may appear in Hong Kong

We have seen Steppe Eagle added to the Hong Kong "list" (photo by Daniel CHAN, ID'd by Paul) by means of a photograph.  I'm sure that if Striated Swallow is going to be added to the HK "list" it will only be with the evidence of clear photos.

This is the challenge... let's sort out those swallows and photograph a HK "First" !

[ Last edited by John Holmes at 6/07/2009 11:42 ]

ajohn

I've always anticipated Striated as a potential species for HK and check any Red-rumped. When they started breeding at Kam Tin, I looked carefully at the birds hoping that they would be Striated. I think the most field guides suggest they are more easily separable than is actually the case in this part of the world. This presumably results from unfamiliarity of most observers with the Chinese races which are most similar to each other. Subspecies elsewhere are very different and, like Paul, I suspect there may be hidden species in this complex.

For what it's worth, when I saw striated in the Philippines it struck me looking rather different from HK birds, seeming larger and bulkier, but I don't know to what extent this was due to context. Plumage differences were difficult to pick up in the field.

Sze

Thank you for the useful information from John Holmes!
Thanks you so much!

And also thank you for the sharing from ajohn!
Thanks a lot!  

Sze

Hi Geoff, Paul and John Holmes!
Due to the request from some Crested Bulbul Club members,I try to translate your discussion in chinese.
Anyone please feel free to tell me, if I make any mistake! Thanks a lot!

由於有部份紅耳鵯的義工對此題目深感興趣，
所以我斗膽嘗試將以上部份討論翻譯成中文，
如我對內容上有任何誤解了的，
煩請大家不吝指正！謝謝各位！


Geoff：

前帖：Geoff  主要參考以下兩本書：《Field Guide to the Birds of South-east Asia by Robson》及《Birds of East Asia by Brazil 》。這兩本書均建議可根據「枕位」（頸後的位置）的紅／橙色部份的大小來分辨斑腰燕（Striated Swallow）及金腰燕（Red-rumped Swallow）。金腰燕枕位的紅／橙色會比斑腰燕大片。另外，斑腰燕體型會較金腰燕略大，下體的縱紋亦較濃密及粗，但這些特徵都並不容易清晰界定。從以上的相片來說，以上燕子的枕位紅／橙色均比較大片，而且牠們下體的縱紋亦不夠濃密，所以應該全都是金腰燕。

後帖：Geoff：當參考過OBC網頁內斑腰燕相片後，我有點猶豫，似乎並不如書中所說那麼容易分辨！



lpaul：

Geoff，我認為OBI網頁內某些相片是錯誤辨認了的！
要分辨斑腰燕及金腰燕實在並不容易！由於牠們兩種之間似乎有很多變種，所以估計這兩種燕子都有多於一個品種！
我找到一個比較快捷的分辨方法，就是根據牠們下體的縱紋形狀來分辨。金腰燕的縱紋相對來說比較窄，而且闊度比較平均；而斑腰燕的縱紋則較粗，而且個別條紋常呈現由頂向底漸闊的形態。但是我亦不太肯定此方法的可靠性。



John Holmes：

我參考的書籍包括：
《A field guide to the birds of South East Asia》 (Robson)
《Birds of East Asia》 (Brazil)
《Swallows and Martins of the World》 ( Turner & Rose)
《Handbook of the birds of the World》- 第9冊（以下簡稱HBW Vol.9）

在HBW Vol.9插圖68（由Hilary Burn）顯示出6個金腰燕的品種，當中包括2種有縱紋的：daurica (少量縱紋) 及japonica (縱紋較濃密的)。 另外有3種斑腰燕品種，包括：vernayi (濃紅褐色及有縱紋)，striolata (少量縱紋) 及stanfordi (縱紋較濃密的)。

插圖（但沒有在HBW內文說明的）支持了Paul對斑腰燕的觀點：縱紋較金腰燕濃密，而且條紋呈現由頂向底漸闊的形態。至於頸後（枕位）紅／橙色斑的大小似乎並不是可靠的分辨特徵。

在香港比較值得注意的是striolata種的斑腰燕，因牠可見於台灣及菲律賓。而且《香港及華南鳥類》一書亦不排除斑腰燕及洋燕在香港出現的可能性。

較早前，由於拍得清晰的照片，草原鵰因而被接納加入香港鳥類名錄內。我預計只要同樣拍到清晰的照片，斑腰燕也有機會被加入香港鳥類名錄內的。

[ Last edited by Sze at 8/07/2009 00:05 ]

lpaul

I'm not sure where the rufous hind collar feature originates - but this also varies with subspecies in Red-rumped.  One of the features for identifying nominate daurica is that the hind collar is interupted with blue (Vaurie: Birds of the Palearctic Fauna).

Whilst it is of course possible that Striated Swallow could occur in HK, this is largely a resident species.  It is also worth noting that the Taiwan populations of Striated are somewhat problematic and that some authorities suggest that these are best placed within Red-rumped.

Mon

多謝Sze的翻譯，使我獲益良多，你的心意，無限感激。

[ 本帖最後由 Mon 於 8/07/2009 23:28 編輯 ]

Sze

Quote:

Original posted by Mon at 8/07/2009 23:25
多謝Sze的翻譯，使我獲益良多，你的心意，無限感激。

[ 本帖最後由 Mon 於 8/07/2009 23:28 編輯 ]

Mon姐! 客氣了! 真的幫到你們就太好了! 只怕我的語文能力不濟, 怕有詞不達意, 甚至翻譯錯誤!

cywong

May I know whether these are Striated Swallows?

JiangXi, Jun06

msamuel

The following photos were taken at Xishuangbanna Tropical Botanic Garden, Yunnan, China in Dec 2010.  According to a bird watcher who is working at the site, the birds are Striated Swallows.




Striated Swallows generally have denser and thicker streaks.

According to "A Field Guide to the Birds of China", they are only found in Taiwan and Southern part of Yunnan in China.  The Guide abandons the use of hind collar characteristics as a differentiation from Red-rumped Swallows.  Having said that, I think the photos posted by cywong above are still Red-rumped Swallows.