Eden Prairie police are warning drivers to stay alert for turtles crossing their roads, even as the reptiles' peak migration season starts to taper off for the year.

In recent weeks, police have received more than a dozen calls related to turtles, according to the department's Facebook page. Officers are urging drivers to call 911 if they see a turtle "causing a hazard to itself or motorists," rather than trying to help the turtles themselves.

Sgt. Lonnie Soppeland said the season for peak turtle migration is winding down but isn't yet over. He said the number of nature preserves in the area makes places like Eden Prairie danger zones for turtles on the move.

But drivers also put themselves at risk of getting hit by other cars when they stop to help turtles, he said.

"If the turtle is in the road, we would rather have a squad car out there with lights to block traffic so that we're able to move the turtle safely off the road," Soppeland said.

Migrating turtles this time of year often move upland from areas around lakes and rivers to familiar nesting locations, and drivers shouldn't be alarmed if they find turtles far from bodies of water, according to the Minnesota Department of Natural Resources.

The DNR's website says that, ideally, drivers should let turtles cross a road unassisted, and not make any rapid movements that would scare them or cause them to stop.

The Blanding's and Wood species of turtles are threatened throughout Minnesota and may not be handled without a special permit, according to the DNR. But in life-or-death situations, the department recommends moving the turtles a few feet off the road for safety and documenting the incident with the Nongame Wildlife Program.

If it's necessary to pick a turtle up, the DNR recommends grasping it gently along the midpoint of its shell and moving it in the direction it was headed.

Carol Hall, a herpetologist with the DNR, said the peak migrating season is generally from late May to mid-June. Much of the metro area is a hot spot for migration because of the number of lakes and rivers, she said.

To help mitigate turtle roadway mortality, the DNR and several other partnering organizations constructed a tunnel in 2014 under Hwy. 4 near Big Marine Lake near Forest Lake, a popular spot that year for crossings of the Blanding's turtle. The tunnel was the first of its kind in the state and included barriers at its openings to help guide wildlife inside.

Since the tunnel's construction, the DNR has tracked turtles and other reptiles, amphibians and small mammals using it, Hall said.

Hall said she's aware of some other proposals for turtle tunnels, though funding is uncertain at this point. Other attempts to reduce roadway mortality, such as "Turtle Crossing" signs, have some benefits but aren't always worth installing, she said.

"It's not really the answer to the problem," she said. "Like a lot of wildlife signs, they just kind of lose their effect over time."

Hall maintained that roadway mortality poses a significant risk to turtle populations, particularly those that are threatened.

"Road mortality can be a significant issue when individual turtles are lost over time," she said. "Populations slowly die out."