My guess is there is a lot more easy food in the area with the increase in tourist numbers. They usually hang out on the Millennium bridge giving you the evil eye. Also, I see we have mating pairs of ducks with an interloper hanging round in the background.
I love the seagulls with their evil eye. Their "guano" probably does some damage, I quite like their screeching though. I got woken up by it on Saturday, which made a difference from the bin collectors or loud "revellers" on their way home.