Along the stretch of coast between our home in Herne Bay and Birchington to the east, lies a sand/mud cliff rising almost vertically at the back of the beach. At this time of year, as reliable as clockwork, something happens here which makes this walk a little bit special. The colony of sand martins arrive here at the completion of their intercontinental migration, returning to their customary nesting holes in the sandy cliff. Nesting season from start to finish sees much activity, and from the nesting function itself through to so the frenzy of feeding feed the hatchlings. That time is here, and Michaela caught some of the action on…