Highlights From Shawell This Week

The highlight for the week was the Caspian Gull below, but I also saw some other splendid gulls...

Near-adult Caspian Gull

My usual Wednesday dinner time stop off at Shawell was a bit miserable and short-lived this week, because of the dreadful weather. I only stayed for about ten minutes, but I did manage to spot a really smart adult or near-adult Caspian Gull. The photo does not really do it justice, as this was a classic bird. Its legs are long and thin and it is long winged. The primary pattern is spot on and its eyes were nice and dark. I initially thought it was one that I saw about a month ago, but after comparing photos of both birds I realised it isn't the same one, so it is a new one for this year.

Adult or Near-adult Caspian Gull

Yesterday the weather eventually improved and for the first time I saw as many colour-ringed Herring Gulls as Lesser Black-backed Gulls. There were loads of gulls at the landfill in the morning, but many off them were resting out of view, Even so there were plenty viewable from Gibbets Lane. Once the tipping finished at about 11:30 it was time to move to the lagoons. My timing was perfect, as a great swarm of gulls arrived at the same time as me. A couple of adult Yellow-legged Gulls were amongst them and they looked very smart. Their fresh summer plumage contrasted with the scruffier winter plumaged Herring and Lesser Black-backed Gulls. 

One of the most eye-catching gulls of the day was the fourth-winter female Yellow-legged Gull in the picture below. It looks adult like, but when it flapped its wings there was a few dark feathers left wherr they should be grey in an adult. The tertials (or according to bloggers auto spell check tortillas) also appeared to show a few dark markings.

Yellow-legged Gull

Amongst the gulls visible from my side of the dividing bank was a third-winter Caspian Gull. Many hundreds of gulls are hidden on the other side of the bank and this third-winter kept disappearing over the crest of the bank and then re-appearing somewhere else. Trying to recreate and do justice to what you see with the eye is difficult when digiscoping and it is made even harder if you are looking into the sun. The third-winter is not one of the two I saw earlier in the month.

Third-winter Caspian Gull

The gulls began to drift off into Warwickshire by about 14:30; mostly heading towards Draycote Water. As the numbers started to dwindle it was tempting to leave, but small groups continued to arrive from the landfill site just to the north. Amongst one of these groups was a fine near-adult Caspian Gull. The photo below shows the text book features: elegant and long winged, a small head, small dark eyes and a longish slender bill.

 Near-adult Caspian Gull

Near-adult Caspian Gull

As normal I was left puzzled  by one of the gulls yesterday. I hadn't been at the lagoons long when I found a smallish gull that at first glance looked like a Caspian. I soon noticed its bill was a little short. I then turned my attention to its primaries and they were more third-winter like, but the gull itself looked more like a fourth-winter or adult. The longest primary (P10) was mostly dark with a small white mirror (see photo below). If it is a third-winter I would expect to see some dark markings on the tail, but it was clean white. Its bill ratio is 2.16. Of the 100 Caspian Gulls sampled in Identification of Caspian Gull. Part 2: phenotypic variability and the field characteristics of hybrids, by Chris Gibbins, Grzegorz Neubauer and Brian Small 13% had a similar bill ratio, but so did 59% of the Herring Gulls and 25% of known hybrids that were sampled. P5 showed a typical black band as far as Caspian Gull is concerned, but this is unusual in Herring Gulls. So this is either a hybrid or an extreme Caspian Gull.  

I have considered whether it could be a Yellow-legged Gull, but its mantle colour appeared too pale and its primary feather pattern, especially on P8, 7 & 6, does not seem quite right. Its bill lacks the steep gonys angle and its dark eyes are unusual amongst Yellow-legged Gulls.

As always comments are welcomed.

Mystery Gull