Sunday, 12 August 2012

Elegant Tern photo shoot

Elegant Terns have typically been midsummer visitors to Britain and Ireland, and it's likely just a very few individuals have been involved. To be completely accurate though, the species still is yet to be admitted formally to the British list and lies in continual limbo amid the threat of pseudo-Elegant Terns and their offspring from further south (France and Spain). Anyway, I saw a fair number of Elegant Terns on Californian beaches last week so felt duty bound to take some shots from the core range and at a time of year that we may expect them here. Click on the photos to enlarge them.

One thing that did grab me though, which doesn't seem to be in the literature too much (though is mentioned in Birding World's orange-billed tern article from July 2003), is the fair amount of adult birds that do not have fully black legs - pretty crazy orange markings in some birds to rather more subtle markings on the foot base on others. In a flock of 122 Elegant Terns on a San Francisco beach on 9th August 2012, 20% of adults in this flock did not have what I would class as black legs. If you don't remember the putative Cayenne/probable hybrid/generally mashed up looking tern at Cemlyn in June 2006, then have a look at some images here - those leg markings remind me of what several Elegants looked like last week. Perhaps the Anglesey bird was therefore the offspring of a mixed Elegant x Sandwich Tern pairing, as I've not experienced that spangled leg look in any of the other species I've seen - and over the years I've seen a fair few Sandwich, Royal and Lesser Crested Terns.
adult Elegant Tern with jazzy orange, spangled legs

same bird as above, with dependent offspring still begging for food
As these photos show they're variable in moult timing and bill colour, structure and length too. Lots of the birds look like those 'classic' carrot-billed birds with decurved paling bills (from blood orange at the bill base) while others are rather less obvious in appearance. Some adults showed rather squat, deep based and concolourous yellow-orange bills similar to what you'd expect in Lesser Crested Tern. Although no birds were solidly black-headed, a few birds did have just a hint of white mottling on the forehead. Also note the neat dark primary wedges on the underwing on all the flying birds.

Note the shortened bill on this bird, as it is not a full adult (dark centred tertials and coverts).
Just a few shots to show the white rumps. I didn't find any birds that showed obviously grey rumps. Admittedly the light was quite bright at times which made assessing this pretty tricky.

And, just to finish off, here are what the 1st year birds look like. Notice the varying leg colour - one bird that I saw had wholly salmon pink legs, to some with seemingly all dark legs.

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