Join for FREE
It only takes a minute!
Zeiss - Always on the lookout for something special – Shop now

Welcome to BirdForum.
BirdForum is the net's largest birding community, dedicated to wild birds and birding, and is absolutely FREE! You are most welcome to register for an account, which allows you to take part in lively discussions in the forum, post your pictures in the gallery and more.

Mystery Gulls from Choshi, Japan

Reply
 
Thread Tools Rate Thread
Old Monday 11th March 2019, 01:18   #1
jmorlan
Hmmm. That's funny -- Opus Editor
 
jmorlan's Avatar

 
Join Date: May 2003
Location: Pacifica
Posts: 2,031
Mystery Gulls from Choshi, Japan

9-10 February 2019. Choshi--Choshi Port, Chiba Prefecture, Japan.

I was unable to match these up with expected Vega or Slaty-backed Gulls. The first might be Mongolian, but after seeing real first cycle Mongolian and discussion with locals decided that it was probably just a variation of Vega.

I'm drawing a blank on the second. Maybe another Vega? Any help would be much appreciated.
Attached Thumbnails
Click image for larger version

Name:	MysteryGullIMG_0709.jpg
Views:	54
Size:	76.7 KB
ID:	689251  Click image for larger version

Name:	MysteryGullIMG_1307.jpg
Views:	64
Size:	120.5 KB
ID:	689252  
__________________
"The nice thing about standards is that you have so many to choose from." A.Tanenbaum

Last edited by jmorlan : Monday 11th March 2019 at 01:25.
jmorlan is offline  
Reply With Quote
Old Friday 22nd March 2019, 13:04   #2
smiths
Registered User

 
Join Date: Oct 2003
Location: the beach
Posts: 866
Hi Joe,

both birds are either Slaty-backed Gulls or perhaps hybrid Slaty-backed x Vega Gulls.
The pattern of the greater coverts does not look entirely typical of Slaty-backed but otherwise the birds match this species pretty well.
smiths is offline  
Reply With Quote
Old Friday 22nd March 2019, 13:22   #3
jmorlan
Hmmm. That's funny -- Opus Editor
 
jmorlan's Avatar

 
Join Date: May 2003
Location: Pacifica
Posts: 2,031
Thanks. I can see that for bird #1. For bird #2, the black wing-tips and white body with checkered mantle are hard to reconcile. We considered worn Slaty-backed, but it did not look worn in the field. Is Great Black-backed Gull a possibility?
__________________
"The nice thing about standards is that you have so many to choose from." A.Tanenbaum
jmorlan is offline  
Reply With Quote
Old Friday 22nd March 2019, 17:43   #4
smiths
Registered User

 
Join Date: Oct 2003
Location: the beach
Posts: 866
Quote:
Originally Posted by jmorlan View Post
Is Great Black-backed Gull a possibility?
Absolutely not.

1w Slaty-backed can show blackish primaries. Upperparts look fine for this species; most of the scapulars are still juvenile and fresh which helps explain the different appearance from more advanced birds like #1.
I do not see a truly white body here, just white head/neck set off from uniform brown flanks - much like bird #1 actually.
smiths is offline  
Reply With Quote
Old Saturday 30th March 2019, 02:26   #5
jmorlan
Hmmm. That's funny -- Opus Editor
 
jmorlan's Avatar

 
Join Date: May 2003
Location: Pacifica
Posts: 2,031
Thanks again. Some folks in a Japanese bird forum think it may be a Caspian Gull or hybrid based on these February 2CY images...

http://gull-research.org/cachinnans/02cyfebr.html

Thoughts?
__________________
"The nice thing about standards is that you have so many to choose from." A.Tanenbaum
jmorlan is offline  
Reply With Quote
Old Monday 29th April 2019, 06:09   #6
smiths
Registered User

 
Join Date: Oct 2003
Location: the beach
Posts: 866
It is all wrong for Caspian Gull: fresh juvenile plumage in February still (!), barred greater coverts, brown flanks, wrong bill shape, short primary projection, and also too much white on the juvenile scapulars.
smiths is offline  
Reply With Quote
Advertisement
Reply


Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Mystery Raptor Japan Wollruss Bird Identification Q&A 5 Monday 24th December 2018 00:54
Vega Gull?, Choshi, Japan Terry Townshend Bird Identification Q&A 6 Tuesday 1st February 2011 09:01
gulls, guls, gulls - Western Japan lostinjapan Bird Identification Q&A 4 Wednesday 5th December 2007 22:59
Mystery passerine from Japan Dave B Bird Identification Q&A 42 Tuesday 11th September 2007 13:31
Choshi Port, Chiba, Japan Charlie M Vacational Trip Reports 4 Monday 13th February 2006 12:48



Fatbirder's Top 1000 Birding Websites

Help support BirdForum

Page generated in 0.21286607 seconds with 19 queries
All times are GMT. The time now is 11:17.