Scarce in Iowa, these Blanding’s turtle hatchlings get head start in UNI lab

The Iowa Department of Natural Resources is hoping to give a claw up to one of Iowa’s most elusive — and most threatened — turtle species by head-starting two Blanding’s turtle hatchlings at the University of Northern Iowa.

“I was like a nervous father,” UNI biology Professor Jeff Tamplin said about monitoring the temperature inside an incubator, where the turtle eggs spent about two months before hatching in early August.

Blanding’s turtles, found in low numbers across Iowa, are an interesting species not only for their distinctive yellow throats and hinged lower shells, but because they can live 75 to 80 years, with female turtles laying eggs throughout their lives.

But like many species, Blanding’s turtles have seen their favored habitat — lakes and wetlands — disappear to farming and development. Females also are at risk from vehicles when they cross roads to lay eggs on dry ground.

The Iowa DNR decided last year to start tracking Blanding’s turtles to learn more about their habits and territories to come up with ways to reduce risks to their survival, said Jenny Fredrickson, a diversity technician in the department’s nongame program.

On one of their first trips to trap turtles and affix radio transmitters, state scientists in June found a pregnant turtle about to lay her eggs in a farm field, which could be dangerous because of equipment use there.

Iowa DNR Clear Lake Unit Biologist TJ Herrick directed the turtle to safer ground. When she laid her clutch, he carefully moved the eggs to Tamplin’s lab, which has an incubator.

Of the 20 eggs, most were not fertilized and only two hatched. Rather than release these tiny turtles into the wild, where they are prime snacks for fish and other animals, the scientists decided to care for them in the lab until they are bigger and have harder shells.

The hatchlings are kept in individual plastic tubs set up like a fish aquarium with gravel and artificial plants arranged so the turtles can hide or climb out of the water to bask under special ultraviolet lights.

“The UVA helps with psychological benefits and induces basking behavior, the UVB induces vitamin D production in the skin which is necessary to metabolize calcium for healthy shell and bone development,” said Tamplin, an Iowa turtle expert whose research is focused on the wood turtle.

Tamplin and his students feed the hatchlings food pellets designed for turtle hatchlings and some general fish food. But when the turtles get bigger, they will get small live redworms or other small crustaceans so they learn to catch and eat live food, Tamplin said.

Scientists don’t know the hatchlings’ gender and it probably won’t be evident until the turtles reach maturity in 10 to 15 years. Because the eggs were incubated in moist sand at 29.5 degrees Celsius — on the warm side — they are more likely to be female than male. Like most turtles, the Blanding’s turtle has temperature-dependent sex determination.

Climate change is putting some sea turtle species at risk because the warmer temperatures are causing more turtles to be female and scientists fear at some point there won’t be enough males. But for Blanding’s turtles in Iowa, females may be in short supply.

“The female that was gravid (pregnant) that we captured was the only female we have captured at that site,” Fredrickson said. “Females are contributing more to the population. If we choose, that would be the preference to get the populations up.”

UNI will raise the turtles until May or June. Then they will be released back into the lake where their mother was found. Because they will be fed all winter, rather than hibernated, the hatchlings should be the size of typical a 3- to 4-year-old turtle by next spring, Tamplin said.

When they are released, the hatchlings will have their own tiny transmitters so scientists can keep track of them without disrupting their lives in the wild.

In Iowa, Blanding’s turtles are considered State Threatened and a Species of Greatest Conservation Need, which means it’s illegal to catch or kill them.

In 2016, Iowa set seasons for hunting a few other turtle species and established a catch limit. The bill also ordered a five-year study to determine if turtle harvest can continue without threatening turtle populations overall. Some states, including North Dakota, Kansas, Illinois and Indiana, have banned commercial harvest of turtles, Iowa Rivers Revival reported.

Some small changes can help turtles, like the Blanding’s turtle. Culverts under roads near ponds and wetlands can keep turtles and other creatures from being crushed by cars. Often fencing is needed to direct the turtles to the culverts, Tamplin said.

“We more try to focus on habitat, managing the (public) lands we have and encouraging landowners to have good habitat,” Fredrickson added.

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