A small sand martin Riparia riparia colony of no more than 30 occupied holes is located on a sheer bank some 2-4m high in a disused part of a sand quarry.
The sand martins come and go in chattering waves in the warm, rain. A kestrel Falco tinnunculus lurks on a nearby wire and flies over creating a rising flock of chattering anxiety. A hobby Falco subbuteo, the most efficient predator of hirundines in Britain, would elicit a special warning call, but none shows.
The young scream from their entrance holes and this brings the obliging parents in to pass small balls of insect food. Sand martins are designed for ephemeral landscapes of sand and water, but damp sand that sticks together and does not collapse as the nest hole is a long, precarious adit into the bank dug out with a stout beak and sharp claws. Large ticks Ixodes lividus rapidly multiply on the adults and young in the nest, some having survived in the cavity from the previous year. Breeding in quarries as well as river banks is uncomfortable and precarious, yet sand martins are both pugnacious and tenacious and extraordinarily successful.
With a world population estimated to be more than 50 million individuals with little evidence of serious declines anywhere in its global range, this little brown bird currently enjoys a winning strategy. The European population migrates to West Africa where it currently contends with fluctuating Sahelian winter rains; perhaps worse is to come from climate change.