2008年9月15日

如何分辨黑叉尾海燕及日本叉尾海燕(Swinhoe’s and Matsudaira’s storm petrel)

Swinhoe's Storm-petrel 黑叉尾海燕 Oceanodroma monorhis 基隆外海
20080909_080 黑叉尾海燕

黑叉尾海燕

原文載自自然攝影中心

貼了一些照片之後 我貢獻一些關於黑叉尾海燕和日本叉尾海燕的資料吧
Reference: Albatrosses, petrels & shearwaters of the world by Derek Onley & Paul Scofeild

本文無圖 可以去網路上自己找XD


節錄一些文字:

General description:

Four all-dark storm-petrels occur in the west and central Pacific: Swinhoe’s, Matsudaira’s, Tristram’s and the rare dark form of Polynesian. Polynesian is simple to identify by wing shape and feeding behavoiur, but the other are difficult. Look for size and flight style, white bases to outer primary shafts, and the extent and contrast of the pale upperwing crescent; note that in all species moult and feather wear can affect the appearance of these features.

四種會出現在西部和中部太平洋的黑色海燕:Swinhoe, Matsudaira, Tristram以及稀有的Polynesian海雀暗色型。Polynesian海雀能夠以翼型及覓食行為與來鑑定,但其他三種則相當困難。要注意體型大小、飛行的方式、外側初級飛羽基部的白色及翼上半月形白色區域的大小及對比等幾種特徵,不過要注意在這幾種海雀之中,換羽以及羽毛的磨損狀況都會影響到上述特徵。

在這邊我只挑出Swinhoe以及Matsudaira兩種的比較來講:



in Swinhoe's Storm-petrel 黑叉尾海燕 Oceanodroma monorhis :

[General description]

A medium-sized, all-dark storm petrel with a
moderately forked tail. Smaller than Matsudaira’s and Tristram’s, about
the same size as Leach’s. In flight looks long, yet rather
broad-winged. ……… The wingbeats are deep and the shortish tail is
usually held closed. Close up, the bill is short and heavy and the
white bases to the primary shafts my be visible, sometimes as a faint
pale patch. Underparts similar to Matsudaira’s, completely dark, become
browner with wear. Where size is difficult to assess may be difficult
to tell form other all-dark storm petrel

為一中型,具有叉尾中等的黑色海燕。體型較Matsudaira及Tristram海燕小,但差不多與Leach海燕相同。飛行的時候看起來很纖長(?),但翅膀顯得比較寬。…略… 拍翅的幅度很大,而他的短叉尾常常是收起來的。如果能靠近點看,可以看見他的嘴喙較短厚及白色的初級飛羽羽鞘基部,但有時候看起來如隱約的淡色斑塊。翼下的顏色和Matsudaira一樣黑,但在磨損的狀況之下會略偏褐色。然而體型大小不是一個用來分辨這四種黑色海燕的好方法。

[Plumage]

Entirely sooty-black except for slightly
paler; crescentic wing bar. Most birds have white bases to shafts of
outer primaries on upperwing but these are unlikely to be very obvious
at sea. All dark, typically robust Oceanodroma bill is relatively short
and deep, with smaller indistinct nostrils. Nostrils of juveniles and
immatures are less prominent than adults.

[Moults and wear]

As plumage wears all feathers become browner,
and pale crescentie wing-bar likely to become more ovious. Likely to
moult on wintering grounds in Indian Ocean.

[Identification]

In Pacific and Indian Oceans range overlaps
with two all-dark storm-petrels, Matsudaira’s and Tristram’s. Both are
larger than Swinhoe’s with more deeply forked tails. … Matsudaira’s has
more prominent white bases to the primary shafts, which can be seen
relatively easily at sea in good conditions. …

在太平洋及印度洋與Matsudaira及Tristram兩種黑色海燕分佈重疊。不過這兩種的體型都較Swinhoe海燕大,而且尾羽分叉較深。…Matsudaira海燕在光線良好的時候可以看到明顯的白色初級飛羽羽軸。


in Matsudaira’s Storm-petrel 日本叉尾海燕 Oceanodroma matsudairae:

[General description]

A large, all-dark storm-petrel with a deeply
forked tail, larger than Swinhoe’s and Leach’s, about the same size as
Tristrua’s but lighter. In moult or worn plumage the bases of the
primary shafts of other species of all-dark storm-petrels can be
revealed and may look like the pale patch on Matsudaira’s, but most
Matsudaira’s can be identified by the prominent white bases to the
primary shafts and smaller, not particularly prominent pale upperwing
crescent.

唯一大型、叉尾分叉深的黑色海燕,體型較Swinhoe及Leach海燕大,而和Tristrua差不多,但較白。在換羽或者羽毛磨損的情形下,其他三種黑色海燕初級飛羽羽鞘基部會有如Matsudaira海燕般的白色斑塊。但大多數的Matsudaira海燕能夠以明顯白色初級飛羽羽鞘基部以及較小,不甚明顯的翼上新月型淡色區域來和其他海燕做區別。

[Plumage]

Head and neck, mantle, back, scapulars, rump
and uppertail-coverts dark brown. Tail blackish, long and deeply
forked. Underpatrs are dark brown. Upperwing-coverts dark brown,
shading to a paler brown on greater converts, forming paler diagonal
bar – often of only a relatively limited extent - on inner wing from
carpal to trailing edge. Primary coverts, primaries and secondaries
blackish-brown, with whitish bases to shafts of outer one to seven
primaries forming small but diagnostic white patch on leading edge of
wing between carpal and ping-tip; underwing uniformly dark brown. Bill
black; iris dark brown; legs and feet black.

[Moult and wear]

In fresh plumage likely to have pale tips to feathers of upperparts typical of Oceandroma. Breeds in northern summer so wing-moult likely to occur after breeding during October-January.

[Identification]

Range overlap with two other all-dark species,
Tristram’s and Swinhoe’s. … From Swinhoe’s by larger size and slower,
more deliberate flight. Swinhoe’s usually has pale bases to shafts of
primaries, as do a few Tristram’s but they are rarely as distinct as
Matsudaira’s.

分佈與Tristram及Swinhoe兩種黑色海燕重疊。… 和Swinhoe海燕相比,具有較大的體型以及緩慢而慎重的飛行方式。Swinhoe海燕的的初級飛羽羽軸基部通常呈灰白,與少數Tristram海燕相似,不過幾乎不會如Matsudaira海燕一般明顯。

結論

大概翻譯了一下 有錯請各位指教
Moult and plumage的地方懶得翻了 有興趣的自己看看 不會太難

簡單心得是:

體型->沒用
尾羽分叉->大多數時候看不出來
飛行方式->可能要看超過一百隻才會有感覺... 但好像的確挺不一樣的

剩下的就只有
1.初級飛羽末端的白色
好像是比較有效的方法 但也會受換羽影響
2.次級覆羽新月狀的白斑 Matsudaira比較淡一些
但光線不好一樣死當Orz


看了兩本書之後(另外一本是20年前的Seabird...)
新的書的確有講比較多 但不超過Seabird對於兩種鳥鬼打牆的外型描述比較之外

比較有趣的是在Seabird當中有提到 Swinhoe拿在手上的時候
會有和Matsudaira一樣白的初級飛羽羽軸

然後寫了一堆才發現前面海燕已經下課了
正在上課的是穴鳥和長尾水薙Orz

3 則留言:

匿名 提到...

一直覺得一眼就能分出來鳥的人是天才,沒想到你就是天才阿!!!!

官能貫 提到...

就是因為分不出來
才要抄書出來讓大家討論一下呀

但論壇上沒人理我Orz

匿名 提到...

天才總是寂寞的(爆笑)