22 Mar 2012

Eastern Woodchat Shrike (niloticus) - Alba Marsh (Bahrain)

A post by Laurie asking if we get badius Woodchat Shrike in Saudi Arabia prompted me to look into the eastern race birds a bit harder. This combined with the fact I have ringed three birds in the last three weeks in Bahrain prompted me to post a few images of Woodchat Shrikes Lanius senator of the eastern race niloticus. They occur from Cyprus, Levant & eastern Asia minor eastwards to Iran and winter in southern Egypt & Sudan.
 Woodchat Shrike (Lanius senator niloticus) - Second calendar year female
 Woodchat Shrike (Lanius senator niloticus) - Second calendar year female
Woodchat Shrike (Lanius senator niloticus) - Second calendar year female

Adults are told from nominate senator by extensive white on tail base measuring 25-35 millimetres and have whiter under-parts with the buff colouration restricted to the flanks. The white patch on the primaries is larger, being 17-20mm beyond the primary coverts in the closed wing of adult males compared to 10-16mm in the nominate sub-species. The female niloticus often has no black on the face even in adult plumage. Juveniles shown extensive moult of the body feathers, particularly the median and greater coverts on migration, with the equivalent moult in the nominate race occurring on the wintering grounds after migration. They are normally paler than nominate with greyer upper-parts. Birds average smaller to the west of their range and larger to the east.
 Woodchat Shrike (Lanius senator niloticus) - Second calendar year male
 Woodchat Shrike (Lanius senator niloticus) - Second calendar year female
 Woodchat Shrike (Lanius senator niloticus) - Second calendar year female
Woodchat Shrike (Lanius senator niloticus) - Second calendar year male


The last bird we caught we measured the white tail base which measure 32 millimetres and the white patch on the primaries which measure 20 millimetres fitting nicely inside the niloticus range. The other measurements of wing length and bill length also fitted for all three birds caught.

Andrea Corso kindly pointed out the following......"I underline that niloticus is easy (to identify) only when typical...however, around the Eastern Mediterranean basin and Middle East there are several clinal populations with birds which are very hard to be positively ID. In the Sicilian Channel islands, for example, we used to see several birds which have really mixed or intermediate characters .... same in SE Italy, in Turkey etc etc"

As is normally the case this shows that birding is not as simple as it at first appears!

3 comments:

  1. Nice shots - i'm off to Maroc in a couple of weeks time and shall be checking Woodchats in coastal areas for poss badius.

    Laurie -

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    Replies
    1. Laurie,

      Good luck - they are a rare in Morocco as far as I can remember. senator occurs as a non-breeding visitor and rutilans as the breeding sub-species. I am not so up on African birding but this is my recollection.

      Jem

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  2. Most useful series of bird in the hand photos Jem - that unmoulted median cov on the 2cy f really stands out. More of the same please.

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