WASHINGTON — Prairie dogs are the sentinels of the Great Plains, much like the famed Paul Revere, sending warnings through their distinctive barks to alert their peers of predators. Their sophisticated calls differentiate between threats on the ground and those from the sky.
“Prairie dogs are considered prey by a wide range of predators,” explained Andy Boyce, a research ecologist in Montana with the Smithsonian’s National Zoo and Conservation Biology Institute. “These include golden eagles, red-tailed hawks, foxes, badgers, and even some large snakes.” Besides, these predators also target other grassland inhabitants like the long-billed curlew.
Recent research published in the journal Animal Behavior highlights that long-billed curlews take advantage of the alarm calls from these prairie dogs. Emily Williams, a Georgetown University ornithologist not connected to the study, mentioned that it’s common for birds to eavesdrop on other bird species for cues about food or danger. However, instances of birds listening to mammals are less frequently documented. “This doesn’t necessarily mean it’s uncommon in nature,” Williams said, “it just signifies a gap in existing research.”
Prairie dogs inhabit vast colonies with intricate burrows that can stretch for miles underground. Upon hearing their neighbors’ alarm barks, they either remain vigilant or scurry into their burrows to evade approaching predators. “Their barks are powerful and can travel long distances,” noted Andrew Dreelin, a co-author and co-worker at the Smithsonian.
The long-billed curlew, building its nests in short-grass prairies, burrows its eggs into the ground. When it detects the prairie dog’s alarm, it responds by pressing itself low into the ground. “This posture, combined with their feather camouflage, renders them nearly invisible in the grasslands,” Dreelin added.
To assess how attuned these birds are to prairie dog alarms, the researchers employed a novel method. They strapped a taxidermied badger onto a remote-controlled vehicle, sending it across the Montana grasslands toward curlew nests. Sometimes, they played recorded prairie dog barks. Observations showed that with these barks, curlews would quickly hide as soon as the badger was about 160 feet away. Without the alarm, they only reacted when the badger was about 52 feet away.
“In essence, the curlews have a better chance of evading predators when they adopt this posture early, prompted by prairie dog alarm calls,” explained Holly Jones, a co-author and conservation biologist at Northern Illinois University. Prairie dogs are labeled “environmental engineers,” Jones highlighted because they create extensive burrow systems and help maintain short-grass ecosystems by trimming prairie grass.
“Beyond their engineering feats, they’re shaping ecosystems through the dissemination of critical survival information,” Jones concluded.