We have an old cherry tree stump which is no doubt where they are breeding. Spotted first male of the year by the stump. Put out some soft apple for them to nibble on. They like soft fruit or a little container of sugared water. For the latter, nothing too big - we don't want them falling in. An old saucer or a jamjar lid would suffice.
I was taking Tea on the patio when I noticed a movement on the lawn. Closer examination showed a female beetle bumbling her way through the grass (and they do bumble a lot!)