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An adult Caspian photographed on Saturday 29 January in southern England. A fine bird when seen standing. But the black in the primaries is rather limited (to about P6) and very solid.

Interesting bird, but I would really like to see a better image with the underwing of the wing tip...

hi neil,

if tongues on pouter 2 primaries were long and extended i'd include this in caspian variability. a view of upperwing tongues would be advisable, hard to see and photograph if not spreading wings (landing, turning).
a have several examples of caspians with reduced black on p5, in exteme cases without any p5 mark. the distribution of black on upperwing is absolutely ok for caspian.

lou

Thanks for your comments Lou and Cristian. Unfortunately, these were the only two worthwhile flight shots I got.

I would be careful to draw any firm conclusions based on this bird. IMO it's hard to exclude any Herring influence in this individual.

Ruud Altenburg wrote:I would be careful to draw any firm conclusions based on this bird. IMO it's hard to exclude any Herring influence in this individual.

i 'm not saying that herring influence is excluded. i just say that caspians with reduced p5 mark are not uncommon in core land cachinnans.

lou bertalan wrote:

Ruud Altenburg wrote:I would be careful to draw any firm conclusions based on this bird. IMO it's hard to exclude any Herring influence in this individual.

"i 'm not saying that herring influence is excluded. i just say that caspians with reduced p5 mark are not uncommon in core land cachinnans.[/quote

Correct, but then again we don´t know what Ruud was refering to?

JanJ

Surely Ruud is refering to the combination of p5 and the perfect argenteus-p10, leaving Herring is a serious option on this one.
Actually, p5-p10 is very good for herring.
Limited p5 markings in core cachinnans area being not uncommon is a statement I would not stand for.
As shown in the cachinnans part, adult cachinnans in Romania in May only occasionally show such a limited amount of black.
Its certainly not as common is not uncommon!

Theo

Theo Muusse wrote:Surely Ruud is refering to the combination of p5 and the perfect argenteus-p10, leaving Herring is a serious option on this one.
Actually, p5-p10 is very good for herring.
Limited p5 markings in core cachinnans area being not uncommon is a statement I would not stand for.
As shown in the cachinnans part, adult cachinnans in Romania in May only occasionally show such a limited amount of black.
Its certainly not as common is not uncommon!

Theo

ok, maybe "not uncommon" is a deceiving statement. i have not yet counted them but i guess the percentage lies somewhere between 4-6% which is a lot.
i don't see p10 being better for argenteus than for cachinnans (dorsal tongues hidden?). bill is another argument, although not as perfect as one might want. i think it's just hard to tell, it could be a cach, could well be something between or even an odd herring (although i don't know such birds).

On the second pic, I see on the hindwing, a very good underside of Herring!

Theo