Photographed today (3/5/2011) I am still learning butterfly identification.
No interactions present.
Chalkhill is ruled out by date and colour, but a magnified view of the photo shows fairly clearly the chequered fringes that indicate Adonis Blue, which certainly flies on Laverstock Down. Also, because of the angle of the wings one can see on the forewings a patch of androconial scales which the Common Blue does not have.
As Michael says, the enlarged view clearly shows the chequered fringes and general absence of the black subterminal line that makes this a male Adonis. Chalkhill is larger, paler, and flys from early July onwards - this is an early year, but not *that* early!
Record your ladybird sightings!
Lat/Lng: 51.07925, -1.76263
OS grid ref: SU167311