Natalie Clements / Colony of Sandmartins (Riparia riparia) entering nesting holes in cliff. Multiple birds enter and leave frame, Abergavenney, Wales, June.

Natalie Clements / Sandmartins (Riparia riparia) landing outside of nesting holes in cliff, as others peer out of them, Abergavenney, Wales, June.

Natalie Clements / Sandmartins (Riparia riparia) perching outside of nest holes with chicks inside begging for food. Two enter and one leaves frame as another flies through, Abergavenney, Wales, June.

Natalie Clements / Sandmartins (Riparia riparia) entering frame and landing on cliff at nesting site, with some hovering near cliff and leaving frame, Abergavenney, Wales, UK, June.

Natalie Clements / Sandmartins (Riparia riparia) entering frame and feeding chicks in holes in bank, with some chicks peering out of the holes, Abergavenney, Wales, June.

Natalie Clements / Sandmartin (Riparia riparia) enters frame and enters nest with chick in it, as another lands outside entrance of nest hole above before turning around and leaving frame, Abergavenney, Wales, June.