Yellow-legged Gull; Gaviota Patiamarilla

These are all the same bird. Pic 6, which was actually taken first, was looking into sun, the effect of this makes the grey back look much too dark for a Yellow-legged, closer to a pale-form Lesser Black-backed. The others I had moved round to its sunny side. This serves to show the difficulties of trying to identify Gulls of the same family (Larus) which have evolved into different species over time, especially when not seen together. At this time of year most Lesser Black-backed will have streaky heads and darker facial patches, several races are possible here along with Yellow-legged, and possible Caspian Gulls which are thankfully rare, only a handful having been confirmed beyond reasonable doubt.