San Diego State biology assistant professor Rulon Clark and a group of select graduate and undergraduate students are gearing up for their annual research season: the prime summer months for observing snakes and their preferred prey, the squirrel, in their natural environment. When the team goes out this year, they’ll have another tool in their snake-observation arsenal.
Clark will take a robotic squirrel designed by faculty from University of California, Davis into the field. Essentially a taxidermied squirrel body with a tail mounted to wag back and forth, it is designed to replicate a behavior known as tail flagging. While the idea of having a robotic squirrel built to “fight” a snake may seem outlandish, Clark explained the straightforward design and purpose of the mechanism.
“It’s a bit frustrating because a lot of the times when stuff like this comes out … the science aspect is often a little complicated and nuanced,” Clark said. “As the person who’s involved in the work, it’s a little bit frustrating to hear ‘some wacky scientist is working on robosquirrel.’”
The robotic squirrel will allow Clark to manipulate the simulated squirrel’s behavior to find why it engages in tail flagging and what effect this may have on a predatory snake’s willingness to strike at it.
A squirrel begins tail flagging when it senses a snake is nearby. It approaches where it believes the snake to be and begins waving its tail back and forth. Clark believes this could be the squirrel signaling to the snake that it is aware of its presence.
“If the predator knows that it’s aware of your presence, it might decide it’s better to go for a prey that’s less likely to escape,” Clark said.
According to Clark, snakes prefer to attack from the rear on unsuspecting prey. They rarely attack enemies head on and rely heavily on the element of surprise.
“Snakes are very cautious about revealing their presence,” Clark said. “So when a squirrel tail flags at a snake, it could be to inform the snake that their presence is known.”
Because of this, snakes rarely attempt to bite a tail-flagging squirrel. The robotic squirrel will allow Clark and his team to manipulate several conditions of the squirrel’s behavior, including body position and even the temperature of the tail to see exactly what part of the tail-flagging technique deters snake attacks.
The team will be using the robotic squirrel while tracking snakes throughout the summer months, using implanted tracking devices and strategically placed video cameras to collect data.