Winter Birding: 1st winter Scandinavian Herring Gulls

The thought of trying to pick out a Scandinavian Herring Gull (Larus Argentatus), amongst a flock of 100's of varied plumaged British Herring Gulls (Larus Argenteus), is enough to put any birder off gulling for life! But fear not my friends, as here is a brief guide to identifying 1st winter Argentatus Herring Gulls whilst out in the field.

This image (Elliot Montieth), clearly shows a typical 3rd winter Argentatus Herring Gull
amongst a flock of 'Argenteus' birds. As you can see its mantle is noticeably darker and this
is how the majority of Argentatus Herring Gulls are picked up.

The key things which I note when I'm out in the field during the winter months when looking through a flock of Herring Gulls, usually tends to be the pattern of the scapulars. This is a good feature to look out for due to the majority of 'Argenteus' birds having already moulted there 1st cycle scapulars and begin to start showing 2nd cycle feathers on the mantle. The 2nd cycle scapulars mainly appear in the the upper half as a result of 'Argenteus' moult occurring earlier than there northern race of 'Argentatus' due to the differences in breeding.

Here's you standard 1st winter Argenteus Herring Gull (Image - Cian Cardiff)

So lets begin shall we ? Insert 1 shows a classic 1st winter 'Argenteus' Herring gull: note the grey scapulars which have replaced the old 1st cycle set and the fact that it has replaced so many scaps this early in the season (Mid-November), it would be very unusal for a 1st winter 'Argentatus' to show this advanced moult.

1st winter Argenteus Herring Gull (Image - Cian Cardiff)

The second insert gives a good view of the scapulars up close on a classic 1st winter 'Argenteus'. Then to compare a not so classic 'Argenteus' a rather dark edge of the scale type bird. This dark bird would throw the most experienced of Gullers, maybe thinking that this bird was within range for a 'Argentatus' or maybe even that of a American Herring Gull! But after seeing this bird over a few hours I got good enough view of all the features needed to ID Herring Gull races, including the tail.

So, here's my step guide to Herring Gull ID for Argenteus (British) and Argentatus (Scandinavian) races.



1st winter Argenteus - Key Features:

  • Body Structure: The majority of birds tend to be a similer size with on occasion a huge male or tiny female mixed in which can cause confusion with other species.

  • Moult: As stated above, the Argenteus moult comes before that of the northern race Argentatus due to earlier breeding in the southern limits of there breeding range.

  • Tail pattern: The tail pattern is consistent of that of a neat black and white flecking along with white edging.

  • Bill: The bill thickness varies massively but is most typically noticeably thin

  • Underwing: The underwing coverts can be rather plain depending on how far north or south the bird has originated from with in general the further south of its original the more washed out it tends to be observed and as you can guess the further north a bird the darker it becomes.



1st winter Argentatus - Key features:

  • Once again and like that of Argenteus, most birds tend to be rather large and bulky, with the exeption to smaller female birds.

1st winter argentatus Herring Gull (Image - Cian Cardiff)

  • Moult: Due to the breeding season of Argentatus being held further north, the moulting is delayed and the scapulars tend to show no second generation feathers in that of text book birds. But as it tends to be there are some of those not so text book birds that have a habit of throwing people off and do that show a couple of 2nd generation feathers. But I find it best to stick with the classic big bulky birds.

  • Underwing: The underwing coverts tend to be very sooty in the 1st winter birds and are rather stand out in my opinion.
1st winter argentatus Herring Gull (Image - Cian Cardiff)

  • Bill: The bill of Argentatus be big and chunky on many males and rather dainty on female birds.

  • By mid winter (December/January), birds tend to go into the first stages of moulting, growing new tail faethers and dropping tail feathers. (Be aware of retarded moulting argenteus)
1st winter argentatus Herring Gull (Image - Cian Cardiff)



This is just meant to be a brief overview these two Herring Gull races and there's more to come! Get finding folks.

Regards, Cian & Elliot

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