Tuesday, 1 February 2011

A veritable exodus of Cormorants

The Safari headed out on the pre-dawn Patch 1 walk to the repetitive strains of Song Thrush Song once again. The avian excitement went quickly down hill as like yesterday the thrush had stopped singing by the time we’d reached the Golden Triangle. About 40 somewhat mobile Magpies were counted at Magpie Wood.
The early morning visit to Patch 2 was on the rising tide so no beach to look over. A sea mist hung low over the water about half a mile out. The first thing we saw was a long line of Cormorants flying parallel to the coast, about 165 of them in all. They were soon followed by another flock of over 200, then another and some stragglers after them, all in all we reckoned on at least 650 and that’s assuming the first flock we saw was the first to leave the roost in the river mouth.
Further out in the gloom we picked up two Little Gulls and three Kittiwakes milling about whilst a dozen Red Throated Divers flew south in ones and twos.
Close inshore was a flock of just four Common Scoters, a Razorbill flew right over them. With the murk rolling in closer to the shore we headed for a warming cuppa.
The lunchtime visit was very interesting...a substantial number of Black Headed Gulls were hovering over the very edge of the water expending a lot of energy, we couldn’t quite make out what it was they were picking out from about ‘a head’s depth’ below the surface, it looked like small fish but not the same as the ‘Pipefish’ they were catching last week, they could have been shrimps/prawns as they looked dark rather than silvery. We didn’t have the big camera and the little one was playing up so we shot back in to the office, it only takes a minute but by the time we’d got back over the road the tide had dropped a fair way and the gulls were now resting on the beach.
Now there were many more Herring Gulls working the shallows, not hovering and plunging but sitting on the water and ducking under and through the incoming waves coming up on the far side with a morsel of whatever, a behaviour we’ve never noticed before. Might try for some better video of the Black Heads and Herrings doing their respective things tomorrow – always assuming they do the same as they did today. On this video at 5 seconds there is an adult Herring Gull that ducks through one wave before riding over the next.

As the tide dropped further there was food on the beach that was easier to collect so those that were still hungry or late coming from the roost argued over whom was having what while the rest started to rest up...the top two are almost the same but can you find the odd one out?

The odd one out is a bit easier to find in this one, and no - it's not the Redshank in the middle of the melee.

We tried to get some wing tip pattern shots to show some of the range of variation in argenteus Herring Gulls but they were no a little far away and the first of several mobile bird flushers had arrived before we got many shots off...really need a dslr and a fast long lens for this kind of caper as you can see from our results.

No 1 is pretty much typical, small white tip to P10 with a fairly big mirror. P9 has a small mirror on the outer web only. There doesn't appear to be any black on P5

No 2 is like our atypical one we found dead recently, a long white tip on P10 and no white on P9 unless there is a mirror on the concealed inner web, no black mark on P5 on this one too.

No 3 appeared to be an adult until it took flight then it showed these immature outer primary coverts. The white moons at the end of the grey tongues on P 7 & 6 are showing nicely. Hard to tell from this blurry effort but the bill doesn't look to have any dark marks on it, 4th year bird or a full adult with a retarded moult?

No 4 has an incomplete narrow subterminal black band to P10, note also the small black mark on P5.

What can we deduce from all this wing tip nonsense - there's no such thing as a 'typical' Herring Gull - QED. If we've made a mistake let us know - it's quite likely so don't be shy.

Got so carried away working through the gulls for little reward we ran out of time to look out to sea.

After work it was still light on the footy field and we had a fly past by the male Peregrine before he went to roost. The Magpies were settling down too all be it rather noisily. Also making a bit of pre-sleep din from the Golden Triangle were an unknown number of Blackbirds being serenaded by (a different?) Song Thrush singing from somewhere behind the electricity plant. A few Robins chittered and twittered from within the Golden Triangle.
Where to next? More of the same if the it's all kicking off again.
In the meantime let us know who’s doing the hovering in your outback.

1 comment:

Warren Baker said...

two of those Cormorants made it here dave :-)