Alongside Alameda Walk a group of Dandelions were attracting several species of hoverfly:
Syrphus ribesii - to get a definite id for this species you need to find a female and check that the rear femur is fully orange. This is a female (note that the eyes do not join at the top of the head)...you'll have to trust me on the rear femora!
Eristalis tenax - the Drone Fly
I took these photos on the way home following a morning walk over Ampthill Park. Highlights included a Spotted Flycatcher suddenly plucking a fly that I was watching out of the air right in front of me, and a patch of scrub alongside Leg O' Mutton pond heaving with warblers: Chiff Chaffs, Willow Warblers, and a single each of Garden Warbler, Whitethroat and Lesser Whitethroat!