Lots of baby bunnies.
Flowers on pine trees, along with last year's baby pine cones and the year before's cones, which are mature and ready to drop off.
Barn swallows have arrived (Black-blue backs, forked tails) and a few swifts (large).
Small birds are busy building nests (watch for them gathering twigs, grass and bits and pieces to line their nests), and feeding their young on the ground or in the hedgerows. The fledglings will very often just sit there, reluctant to fly off because they haven't yet mastered the technique. Sometimes they follow Mum around, begging.
First caterpillars in my garden. Look closely at any plant with chewed or damaged leaves. The caterpillars are still tiny, and generally leaf-coloured.