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Subject: [Eagles] Eastern/Western[?] Marsh Harriers in Fight (澤鷂/白頭鷂[?]) [Print This Page]

Author: jsk_ppp Time: 22/11/2015 00:03 Subject: Eastern/Western[?] Marsh Harriers in Fight (澤鷂/白頭鷂[?])

Mai Po - 14 November 2015

[ Last edited by jsk_ppp at 1/12/2015 21:01 ]

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Author: lpaul Time: 22/11/2015 07:34

Nice pictures. Do you have more pictures of the right hand bird. Especially showing the underwing pattern and the rump pattern? Thanks

Author: jsk_ppp Time: 22/11/2015 08:29

Yes, I have, but I can only upload the photos tonight.

Author: jsk_ppp Time: 23/11/2015 00:17

Some photos of the right hand bird are added for reference. I have more, but due to the daily upload quota, I only uploaded three of them. Is it possible that it is a Western Marsh Harrier?

[ Last edited by jsk_ppp at 23/11/2015 00:22 ]

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Author: lexusjohn Time: 23/11/2015 08:37

Great shots !!!

JSK_PPP Good job

Author: Jonathmartinez Time: 23/11/2015 10:35

the underwing pattern of the outer primaries fit well for Western Mars Harrier (note the limited pale area at the base of the outer primaries), but the head pattern and the yellow streak on breast suggest that it is not a pure bird and probably have some Eastern Marsh Harrier origin as well. Nice looking bird...

Author: jsk_ppp Time: 23/11/2015 13:49

Thank you John.

Author: jsk_ppp Time: 23/11/2015 13:51

Thank you Jonathan. Do you mean that this bird is kind of a mixed species with both Eastern and Western Marsh Harrier origins? Thanks.

Author: Jonathmartinez Time: 23/11/2015 14:17

yes exactly, but the situation is very unclear especially about which features is reliable or not to exclude any hybride, maybe some of the features especially about head pattern and streaks on breast are just a case of moulting issues. The underwing pattern suggests that this bird has strong Western Marsh Harrier influence, and it could be possible that this bird is simply just a Western Marsh... As Paul said, good pictures showing the rump may be of great help to better document this bird.

Author: jsk_ppp Time: 23/11/2015 20:25

Thank you. Let me find the pictures with its rump tonight.

Author: jsk_ppp Time: 24/11/2015 00:22

Two photos added showing its rump.

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Author: jsk_ppp Time: 25/11/2015 00:33

Photos added.

Author: Jonathmartinez Time: 25/11/2015 11:18

the broad and pale tip on one of the uppertail covert is probably indicating some Eastern Marsh origin as well, on a pure Western I would have expect uniform brown or with a slight rufous tip uppertail covert but not as contrasting as on this bird....So an Hybrid to me...

Author: lpaul Time: 25/11/2015 12:15

I think the under-wing is spot on for WMH and that the breast, forewing, and rump markings are all within the range of WMH. The biggest problem in my mind in the head pattern. The dark eyestripe is just too poorly defined and does not reach the base of the bill as it should on a juvenile WMH. I also think that the crown is too streaked. Below is a link to a useful online article discussing EMH and WMH hybrids.

http://www.birdskorea.org/Birds/ ... arsh-Harriers.shtml

Author: jsk_ppp Time: 25/11/2015 20:58

Thank you Jonathan and Paul. It is indeed very difficult to identify raptors, given their individual variations and that it takes several years for them to become adults.

Author: tampccw Time: 20/12/2015 15:56

Superb !

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