White Headed Cormorants
Lol
I was quite surprised this morning to find two Cormorants on the local
lake, both with white heads and virtually identical. My initial
impression was that they were probably partial albinoes ... but am
reliably assured that they are a continental variant of the common Great
Cormorant.
Does anyone have any info/experience of this sub-species ??
--
Lol Middleton - Sully, Vale of Glamorgan - L...@Lolm.demon.co.uk
IEvans9195
Could these have possibly been juveniles rather than a sub-species ? Near
Portsmouth at Langstone Harbour there have recently been several with
semi-white heads which I have taken to be young birds in their first
winter.
Mark Hardwick
Lol <Lo...@lolm.demon.co.uk> wrote:
>I was quite surprised this morning to find two Cormorants on the local
>lake, both with white heads and virtually identical. My initial
>impression was that they were probably partial albinoes ... but am
>reliably assured that they are a continental variant of the common Great
>Cormorant.
>Does anyone have any info/experience of this sub-species ??
>--
Lol
This is actually quite complex.
The continental race you refer to is P.c. sinensis and they do indeed
have white heads in adult summer plumage (don't worry about the
"summer" bit - quite a few Cormorants are already in breeding
plumage).
"White-headed" Cormorants occur regularly in the south (and elesewhere
I guess) and it used ot be supposed that these were all sinensis
birds. However, there was a paper published sometime in the late 1980s
(sorry cannot remember exactly when or where) which altered this view
and pointed out that a number of the birds breeding in western Wales
have white heads. I would guess that is where your birds hail from. It
seems safest to assume mowadays that British cormorants can have white
heads and that this is kust a plumage vairation.
Best wishes
Mark H.
Daan Sandee
In article <pVq+pHAp...@lolm.demon.co.uk> Lol <Lo...@lolm.demon.co.uk> writes:
>I was quite surprised this morning to find two Cormorants on the local
>lake, both with white heads and virtually identical. My initial
>impression was that they were probably partial albinoes ... but am
>reliably assured that they are a continental variant of the common Great
>Cormorant.
>
>Does anyone have any info/experience of this sub-species ??
>--
The continental subspecies, Phalacrocorax carbo sinensis, breeds from the
Netherlands S and E into China. The nominate subspecies, P.c.carbo,
breeds in the British Isles and Scandinavia (and eastern North America.)
P.c.sinensis has a lot of white on the head and neck, often appearing
almost completely white-headed. (Immature cormorants, of any subspecies,
may have extensive white on the throat, but are always dark brown with
dingy white, as opposed to the glossy black with brilliant white breeding
plumage of the adults.) Any decent field guide should explain this ;
see Jonsson, p.54.
Those birds are supposed to stay to the east but I see a number of them
every year in Massachusetts, where P.c.carbo is common in winter but a
rare breeder.
Daan Sandee
Burlington, MA Use this email address: sandee (at) cmns . think . com
R Slack
Lol wrote:
>
> I was quite surprised this morning to find two Cormorants on the local
> lake, both with white heads and virtually identical. My initial
> impression was that they were probably partial albinoes ... but am
> reliably assured that they are a continental variant of the common Great
> Cormorant.
Sounds pretty much as though the birds you describe were sinensis
Cormorants, especially if they had large white thigh patches too? Adult
Cormorants, particularly older birds, can show very white/grey heads, and
are frequently mistaken for sinensis, but their head colouration is never
to the extent of a sinensis, and they always possess quite a small thigh
patch.
Keep looking I'm sure there may be more birds over the spring period.
Russell
Colin Davies
Lol wrote:
>
> I was quite surprised this morning to find two Cormorants on the local
> lake, both with white heads and virtually identical. My initial
> impression was that they were probably partial albinoes ... but am
> reliably assured that they are a continental variant of the common Great
> Cormorant.
>
> --
> Lol Middleton - Sully, Vale of Glamorgan - L...@Lolm.demon.co.uk
I always assumed white headed Cormorants were continental birds, but
there are so many, especially at Seaforth in spring, that I guess some
British birds must show this plumage variation. They are certainly very
handsome birds in this plumage, not a bit like the scruffy looking
individuals that frequent such places as Eccleston mere in winter.
Regards
Colin
Lol
In article <5cg7m3$2...@cherry.news.easynet.net>, Mark Hardwick
<mhar...@valu-trac.com> writes
>Lol <Lo...@lolm.demon.co.uk> wrote:
>
>>I was quite surprised this morning to find two Cormorants on the local
>>lake, both with white heads and virtually identical. My initial
>>impression was that they were probably partial albinoes ... but am
>>reliably assured that they are a continental variant of the common Great
>>Cormorant.
>
>>Does anyone have any info/experience of this sub-species ??
>>--
>
>Lol
>
>
>The continental race you refer to is P.c. sinensis and they do indeed
>have white heads in adult summer plumage (don't worry about the
>"summer" bit - quite a few Cormorants are already in breeding
>plumage).
Yes .. the birds in question did have ver prominent white 'breeding
patches' .. a diagnostic aspect of breeding plumage AFAIK .. so that
ties in ... and also discounts the very reasonable possibilty of
Juvenile plumage in another post ( thanks to IEvans )
>"White-headed" Cormorants occur regularly in the south (and elesewhere
>I guess) and it used ot be supposed that these were all sinensis
>birds. However, there was a paper published sometime in the late 1980s
>(sorry cannot remember exactly when or where) which altered this view
>and pointed out that a number of the birds breeding in western Wales
>have white heads. I would guess that is where your birds hail from. It
>seems safest to assume mowadays that British cormorants can have white
>heads and that this is kust a plumage vairation.
>Best wishes
>Mark H.
Wow !! Does that mean that at last we are totally independent I wonder?
.. and Wales can now be considered to be 'Continental' ?
How come the Cormorants were the first to know I wonder ... hey Malcolm
do you want me to send you some Cormorants so we can annexe Islay .. I
will only help if you promise to bring down the price of Lagavulin :-)
( mind you I would gladly pay twice the price sooner than miss :-)
Seriously though, thanks for that Mark, very informative.