A grassland bird eavesdrops on prairie dog calls to keep itself safe from predators

Long-billed curlews (Numenius americanus), a North American bird species, eavesdrop on the barks of prairie dogs (Cynomys ludovicianus) for intel on the approach of predators. Prairie dogs have specific calls that alert their neighbours if a predator is closing in by land or by air. When nesting curlews hear these barks, they press their bodies to the ground, which makes them “essentially invisible on the Plains”. Without the cues, researchers were able to get a remote-controlled ‘predator’ within 16 metres of the birds before they sensed danger.