Friday 10 June 2011

Adulthood in two years.

Just one of the numerous recently fledged Black-headed Gulls (Chroicocephalus ridibundus) that is starting out on its two year quest to reach maturity.

The juvenile plumage initially develops with the head and upper parts becoming more ginger-brown. Its first moult (post-juvenile moult) usually starts after the bird first flies [check out  this link] when just the head and body feathers will be renewed.

This is a 1st winter bird still showing the retention of some of its juvenile feathers including the dark tail but with the distinctive black tipped yellow bill. Through its first summer it will hold onto some of the faded juvenile plumage but may acquire a partial dark hood, often heavily spotted white, plus the legs and bill base will change to a more orange-red.

Above is an adult in its winter plumage sporting the bold dark ear spot and black tipped red bill. Its spring moult is also a partial moult when only the head and body feathers are renewed.
 
At the end of the its two year moult cycle this years juvenile (image 1) will look much the same as its adult parent showing that distinctive dark chocolate-brown cap plus the red bill and legs.   FAB.

21 comments:

  1. that's a long time to adulthood, i'd think! :)

    ReplyDelete
  2. Theresa ... it takes most gull species 3 to 4 years and us just a little bit longer!!

    ReplyDelete
  3. Terrific post paired with wonderful photos to illustrate the maturing of Black-headed Gulls! Fantastic!

    ReplyDelete
  4. Frank what a splendid summary and the images are superb~

    ReplyDelete
  5. And it's no wonder I have trouble trying to ID gulls! lol

    Great set Frank.

    ReplyDelete
  6. Thank you Julie.

    Thanks Mary.

    Hi Keith. I have the same issues but at least the Black-headed is relatively easy!

    ReplyDelete
  7. wonderful gulls, wonderful shots

    ReplyDelete
  8. Thanks for the explanation. I'll try to remember for this fall when they'll be back :)

    ReplyDelete
  9. Gulls are very difficult for me to id. It seems I am not alone. Great pictures.

    ReplyDelete
  10. That is quite a change of plumage. VEry beautifully illustrated.

    ReplyDelete
  11. Good series Frank!! Boom & Gary of the Vermilon River, Canada.

    ReplyDelete
  12. A very handsome bird! Terrific photos too!

    ReplyDelete
  13. A great series. Very nice to see the complete moult sequence like this.

    ReplyDelete
  14. Perfect series. You've got the entire process beautifully photographed!

    ReplyDelete
  15. Wonderful series on the gulls. They do change in appearance as they age.

    ReplyDelete
  16. Informative post, well-illustrated with your wonderful photography!

    ReplyDelete
  17. They really do a lot of changing don't they? Great post!

    ReplyDelete
  18. They are a beautiful bird, especially the adults! Great shots!

    ReplyDelete
  19. Beautiful informative series, Frank. Great shots!!

    ReplyDelete
  20. Hi Everyone. Thanks for all your comments while I've been away. If only all gull species plumages were this easy to comprehend ... birding would be so much easier..lol. FAB.

    ReplyDelete

I hope you enjoyed your visit and I appreciate your comments.