A group of researchers lead by Rulon Clark of San Diego State University has taken a high-tech approach to studying wildlife interactions, specifically the predator-prey relationship of the rattlesnake and California ground squirrel in the Blue Oaks Ranch Reserve in California. Using a robotic squirrel, the team is studying whether different tail-flagging behaviors change the likelihood of a rattlesnake to strike.
California ground squirrel pups make up to 69 percent of the rattlesnake's diet, but it the squirrel is also capable of neutralizing the snake's venom, which allows it to stand its ground in order to thwart attacks. The squirrel has been seen tail-flagging in the presence of rattlesnakes or when they believe rattlesnakes are nearby, a technique that the researchers think is used to warn a rattlesnake that their presence is known and that a surprise attack won't work.
Clark and his team in partnership with the National Science Foundation have been studying rattlesnake attacks by placing mini wireless video cameras at the site of tagged rattlesnakes that have assumed the coiled position and are likely waiting for hunting opportunities. The videos are helping them to understand the process the snakes use to attack their prey and their success rates, but now they have a tool that will let them figure out if the squirrel's tail has any effect on those things.
The National Science Foundation says, "To test Clark's ideas about vigilance advertizing and perception advertizing from squirrels, he and his research team are currently recording controlled encounters between live rattlesnakes and a life-like robotic squirrel, which can be programmed to wag its tail. What's more, its body can be heated by copper coils to anatomically correct temperatures, and its tail temperature can be increased above its body temperature during predator-prey interactions. The robotic squirrel's body is made from taxidermic skin, and it has a realistic smell because it is stored in squirrel bedding when off-duty."
The team is currently performing tests where the robo-squirrel's tail is motionless, wagging or wagging and heated. They will compare the rattlesnake's response to the different behaviors and see if the tail signals perform different functions or none at all. They'll also study whether how close the squirrel is to the snake or how long they flag makes any difference in whether the snake strikes.
You can see a video of the robotic squirrel flagging a rattlesnake below.