A beautiful day, and some interesting gulls to see. This first-winter Black-Headed Gull is a visitor from Finland on its first trip abroad.

Its ring says: ST294.731 MUSEUM ZOOLOG HELSINKI FINLAND. One of the regular ring observers has already noted its arrival, so it will go into the records.

This gigantic creature is a first-winter Great Black-Backed Gull, the first I have ever seen.

I noticed it because of its size, but had to go home and check that it was not a very large Lesser Black-Back or Herring Gull. But I am pretty sure of this one: the B-shaped front edge to the darker feathers on its folded wings is distinctive. Great Black-Backed Gulls are serious predators and often take pigeons. If this one stays, it will join the resident Lesser Black-Backs in the hunt for the park's Feral Pigeons.

And here, to complete the set of young gulls, is a first-winter Common Gull.

When adult they have pale grey backs like Black-Headed Gulls but are larger, with no black spot behind the eye and pale legs of a light greyish straw colour, and are easily spotted in flight by the white 'window' on their otherwise black wingtips. There are now quite a few of these winter visitors on the Serpentine. But they are not nearly as common as the Black-Headed Gulls. Sometimes you see them chasing the smaller gulls to take any food they are carrying, or whirling gracefully around in tight circles as they dispute the ownership of a bit of bread.

The pair of Tawny Owls were dozing peacefully side by side in the sunlight at the top of their nest tree.