Ageing Herring Gulls

[adriaens]

Thought I'd start a new thread on this, rather than post it under the Vega Gull one.
Here is a Herring Gull (blue CCAD) that I would have aged as a 2nd-cycle in the field, were it not for its colour-ring:
https://picasaweb.google.com/lh/view?uname=Zorkyyy&isOwner=true&tags=CCAD#

Except for the colour-ring, there is not much that betrays this bird's true age, I think. All primaries look really similar to 2nd-generation feathers: no white mirror, no white apical spots, slight brown tinge on inner primaries, only thin white tips to inner primaries. On the right wing, one or two inner secondaries show an adult-like pattern (blue-grey, with broad white tip), but such feathers are not present in the left wing, so, in theory, they could have been acquired through accidental loss. The only thing is probably the tail band, which is normally broader and more solid in 2nd winter.

[Brian S]

Sorry Peter, I may be missing this and probably irrelevant, but when were the photos taken? The primaries in particular look strange for a 3rd cycle Herring.

Brian S

[adriaens]

They were taken last Sunday (7 Feb 2010). The date should be visible in the column on the right of each photograph, above the map with photo location. Clicking on "more info" will also give you the file name and EXIF information. In addition, clicking on the magnifying glass just above the top right corner of each photograph will give you a slightly larger version of it.

I certainly agree that the primaries look like 2nd-generation, but the bird is a 3rd-cycle none the less. It was ringed as a pullus on 10 July 2007.

[JanJ]

A good example Peter of an old problem so to speak. Can we confidently age - in this case, Hering Gulls. Quite straightforward in first cycle but in older 'subadults' it´s more unreliable - hence 'type' 2 cy, 3cy or what ever term people prefer to use. I remember an article in British Birds back in the begining of the 80's, I think (maybe Brian or someone else remembers?), where photos of ringed Herring Gulls showed various plumage featuers not reflecting their true age - in a similar fashion to Peter's bird.
I think, however, nowadays with more extensive ringing project going on - we have learned more about the development of plumage features and the variation in Herring (and other taxa) and more is hopefully to come. Among others, Peters bird highlights the problematics of ageing gulls correctly.

JanJ

[W. Ruskin Butterfield]

Monaghan, P., and N. Duncan. 1976. Plumage variation of known-age Herring Gulls. British Birds 72:100-103. ??

[JanJ]

Monaghan, P., and N. Duncan. 1976. Plumage variation of known-age Herring Gulls. British Birds 72:100-103. ??

Yes, that´s the one. Thanks!

JanJ

[adriaens]

Check out 'blue KS.AV' on https://picasaweb.google.com/lh/view?q=KSAV&uname=Zorkyyy&psc=S# :
colour-ringed as an adult in 2008; metal-ringed in 2001 so at least 9 years old.
It still has remnants of a blackish tail band!

[adriaens]

Another Herring Gull that may be difficult to age is "yellow 2V" on https://picasaweb.google.com/lh/view?uname=Zorkyyy&isOwner=true&psc=S&tags=2V#

Again, it is a 3rd-cycle bird that looks more like a 2nd-cycle. The inner primaries are bluish-grey - a bit adult-like - but not convincingly so.

I have the feeling this is going to be a regularly updated topic :frown:

[adriaens]

Hard to believe perhaps, but this argenteus, looking like a retarded 3rd cycle, is actually already in its 4th cycle, as shown by the ringing data...

https://picasaweb.google.com/Zorkyyy/4cEuropeanHerringGullColourRinged#5589858964512872 034

Photo taken on 10 March 2011. This bird was ringed as a pullus in July 2007, and has been reported regularly since.

[JanJ]

Yes, another good example how impossible it is to age LWHG if not ringed.
I would never have guessed the age of this Herring.

JanJ

[adriaens]

Another interesting puzzle, though technically not a Herring Gull this time.
I photographed this American Herring Gull at Half Moon Bay, California, on 6 February 2011. I have no idea about its exact age. All of its primaries are 2nd generation, but its tail feathers and most of its secondaries are 3rd generation!
So: 2nd winter or 3rd winter ? Take your pick...

5182

5183

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[JanJ]

Another interesting problematics (if you like), which btw never cease to end of course. Peter´s wording, 'take your pic' sems quite relevant. So, should we judge from the tail or the wing, with the outer, and especially (?) inner primaries looking like 'standard' 2nd cycle, as does the coverts and tertials.
Maybe it´s a matter of taste, but I´m rather fixed on the tail, which means that I could go for a 2nd cycle - which is based on the amount of 2nd cycle features. Doe´s that make any sense. :puzzled:

JanJ

[lou]

Another interesting problematics (if you like), which btw never cease to end of course. Peter´s wording, 'take your pic' sems quite relevant. So, should we judge from the tail or the wing, with the outer, and especially (?) inner primaries looking like 'standard' 2nd cycle, as does the coverts and tertials.
Maybe it´s a matter of taste, but I´m rather fixed on the tail, which means that I could go for a 2nd cycle - which is based on the amount of 2nd cycle features. Doe´s that make any sense. :puzzled:

JanJ

if you're fixed on the tail the logic answer would be 3rd cycle, jan? but i ask myself if such rectrices could be 2nd gen? and beside the adult grey right sec. 4, could the dark centered ones also still be 2nd gen? or are those white tips much too wide? probably. still the bird as a whole looks very much like a 2nd cycle smith, esp. judging by its primaries.

lou

[JanJ]

Meaning Lou. By being 'fixed' on the (looking) older than 2nd cycle tail other mentioned features call for 2nd cycle.

JanJ

[adriaens]

As far as I know, such largely white tail feathers do not occur in 2nd-cycle Am. Herring Gull, and neither do such white secondaries (with black spots). The pattern exactly matches that of 3rd cycle.
Note, however, the outermost 3 secondaries in each wing; these are brown, and look like 2nd-generation!

From colour-ringed European Herring Gulls, we know that 'advanced birds' are very rare at best. For instance, birds looking mostly like 2nd cycle (brown wing coverts, brown outer primaries, brown secondaries, brown tail,...) but with blue-grey inner primaries have invariably turned out to be in their 3rd cycle, just showing a retarded plumage.
However, the subject bird is not a European Herring Gull, and it was photographed in California (a different cilmate), so who knows...

[LeeEvans]

This problem of accurately assessing the ageing of LWHG in the field was brought home to me when sending in details of colour-ringed birds I had seen to Peter Rock in Gloucestershire. I could not believe the returns I was getting from known aged birds that Peter had ringed in the Avon and South Glos region - some birds appearing second or third calendar year were much older. It is a minefield and takes 'individual variation' to new levels.

[adriaens]

Check out 'blue KS.AV' on https://picasaweb.google.com/lh/view?q=KSAV&uname=Zorkyyy&psc=S# :
colour-ringed as an adult in 2008; metal-ringed in 2001 so at least 9 years old.
It still has remnants of a blackish tail band!

Blue KS.AV is still around (now 10.5 years old at least), and still has the same tail pattern with black spots:
https://picasaweb.google.com/115659792470435170210/AdEuropeanHerringGullsColourRinged#568497381416715 1330
https://picasaweb.google.com/115659792470435170210/AdEuropeanHerringGullsColourRinged#568497383202040 3314