DOT says pond-building effort is working for turtles

Highway 100 extension project requires effort to protect local wildlife

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CEDAR RAPIDS — But are the turtles smiling?

That’s the question from Wally Taylor, the Cedar Rapids environmental attorney who has been seeking to block the long-delayed, $200-million project that will extend Highway 100 from Edgewood Road NE west and south to Highway 30.

Both of Taylor’s lawsuits on behalf of the Sierra Club Iowa Chapter were dismissed this month, one in state court and one in federal court, even as the Iowa Transportation Commission approved full funding for the 7.5-milelong highway project in its five-year construction plan and as the Iowa Department of Transportation continues the project’s pre-construction work.

Out at the area where the new four-lane will pass near the original, state-sanctioned Rock Island Botanical Preserve next to Xavier High School, Terry VanDeWalle, senior consulting biologist at work for the DOT, had some thoughts about smiling turtles.

A reptile and amphibian specialist, VanDeWalle has been working with the DOT on the Highway 100 extension project for a decade, stretching all the way back to early environmental studies for the project to see what its effect would be on the local turtle population and, particularly, on the Blanding’s turtle, which enjoys special status on the state’s list of threatened species.

The DOT can’t build a highway without taking steps to help the Blanding’s turtle live with it.

Last week, VanDeWalle, of Stantec Consulting in Independence, and Mary Kay Solberg, a senior environmental specialist with the DOT, showed off a newly constructed turtle pond to emphasize the care that the highway project is taking with the Blanding’s turtle.

VanDeWalle and Solberg say the new pond appears to be doing everything that was hoped for it. In fact, VanDeWalle went so far as to suggest that the Blanding’s turtles and the larger number of painted turtles and snapping turtles in the area very well may be smiling.

“We assume they are happy when they’re lounging on logs and basking in the sun because that’s what they naturally do,” he says.

Road progress

Fussing with the turtles in this spot next to and at the Rock Island Botanical Preserve — which includes additional land donated to the original preserve 11 years ago as the project was moving toward construction — is among the first pieces of the highway construction project. Bids for the project’s new bridge across the Cedar River and for the grading of the highway roadbed are slated for early 2014.

To accommodate the turtles, the DOT late last year oversaw the construction of the new turtle pond at a cost of about $77,000, which has been built so its north edge is only 15 or so feet from the south edge of the old pond. The slope next to the new highway would have extended about half way into the old pond, so a new one was needed, the DOT’s Solberg explains.

It was vital, said VanDeWalle, to have the new pond as close as possible to the old one because Blanding’s turtles and turtles in general have a strong sense of home. “They like to go to the same place, over and over again,” he says.

Each year as winter approaches, these turtles go into hibernation at the bottom of ponds, either by lying at the bottom or burrowing into the mud there.

Actually, there are three ponds or wetlands in and around the Rock Island Botanical Preserve that painted turtles, snapping turtles and the protected Blanding’s turtles share when they emerge from hibernation in early spring until they return to hibernation as winter approaches.

However, VanDeWalle’s research has revealed that all or nearly all the turtles hibernate in the one pond that now has been moved, probably because the others at times don’t have any water in them.

“So the question of why is this pond important?” says VanDeWalle. “ If that pond goes away, none of these turtles have a place to hibernate, and this population won’t survive. ... This (new) pond is right here, where the turtles expect it to be.”

With the new pond in place this spring, VanDeWalle set up an enclosure around the old pond so turtles could not leave it. Using bucket traps, he then captured all 200 or so turtles as they emerged from the old pond and placed them in the new pond.

Now, with summer here, the turtles continue to use the new pond but also make their way among it and two other ponds that are less than a mile apart, he says.

In the mix of turtles, VanDeWalle has found nine of the threatened Blanding’s turtles. One has died, a victim of a predator, likely a raccoon, that chewed a leg off. Seven others have transmitters on them while the eighth had a transmitter dislodged.

Environmental attorney Wally Taylor points to the turtles’ strong homing instinct and says moving the pond isn’t going to work.

“Of course, the DOT is going to say everything is just fine,” he says.

His and the Sierra Club Iowa Chapter’s lawsuits to block the Highway 100 extension, he adds, has been more than a fight over one animal or plant species. The litigation has attempted to defend “a unique ecosystem,” Taylor says.

VanDeWalle and Solberg note that none of the three ponds near or in the nature preserve is a natural pond.

Solberg says the pond that has been moved was dug by a homeowner for his fish about 30 years ago, and VanDeWalle says it’s “about as bad as it gets” when it comes to natural habitat.

“It literally was just a hole in the ground,” he says. “The water quality is bad. But the critical element: It had water in the winter. … So there’s no reason to believe the turtles won’t use the new pond. They used that (the old one).”

Pond design

In building the new pond, which is fed by groundwater, VanDeWalle and the DOT had some 10 years of hydrological data and plenty of information on turtle movements that went into the pond design. It is five-and-a-half feet deep and 27,200 square feet in size, compared the old pond’s size of about 16,000 square feet, according to the DOT.

Yet to come, says Solberg, is a box culvert — 105 feet long and 10 feet wide and 10 feet tall — to allow turtles, deer and other wildlife to make their way under the new highway to a pond, known as the Swan Pond, on the new roadway’s north side.

Across the river, the DOT also has purchased 30 to 40 acres of property to create a new sand prairie to accommodate another species of turtle, the ornate box turtle, which, too, is on the state’s threatened list.

The new highway also will feature an animal barrier fence to keep deer and other wildlife off the highway as well as a bend in its alignment on the east side of the river to avoid a state-protected grass species, says Solberg.

Even without the new highway, VanDeWalle says the population of turtles now in the vicinity of the preserve is in trouble because of the way that development has closed in around them over the years. He points to the Swan Pond and says that the fertilizers that run off lawns from nearby developments, pollute the pond’s water, suck oxygen from it and compromise it for wildlife.

He also notes that only one of the eight known Blanding’s turtles in the vicinity is a male, and on a recent check, none of the female Blanding’s turtles was carrying eggs.

VanDeWalle speculates that the cold wet spring may have delayed reproduction or maybe the lone known male is only now coming of age and able to fertilize eggs.

A highway that is about to be built, he says, can’t change a species’ prospects if only one sex of Blanding’s turtles is left in this spot.

“If one sex disappears, you have a ghost population,” VanDeWalle explains. “But I’m not willing to concede that yet.”

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