Blanding’s Turtle

One of North Iowa’s rarest forms of wetland wildlife

by Lowell Washburn

With its distinctive high-domed helmet-shaped upper shell, bright yellow throat, and endearing smile, it would be hard to mistake the Blanding’s turtle for anything else.  Sadly, it is a species that most Iowans will never have an opportunity to view.  There are exceptions, of course.  Like the adult Blanding’s recently seen making its way across Cerro Gordo county’s busy S14 blacktop that runs adjacent to Wild Goose Marsh, a 157-acre DNR managed public wetland located four miles north of Ventura.

Road crossings are extremely hazardous for Iowa turtles.  Many are killed – especially during late spring and early summer when large numbers of adults leave native wetlands in search of drier soils where they can dig nests and lay their eggs.  The ongoing danger was graphically illustrated when the tires of an oncoming vehicle missed the slow-moving Blanding’s by mere inches.  It was a near miss that could have easily ended the life of one of Iowa’s most interesting, but rarest, forms of wetland wildlife.

Fortunately for the Blanding’s, the next vehicle was driven by Iowa Conservation Officer, Matt Washburn who pulled aside to ensure the turtle did not become the species’ latest grim statistic.  A magnificent specimen, the Blanding’s was the largest Washburn had ever encountered and well worth taking time to weigh and measure before letting it continue its journey.  With a carapace [top shell] measurement exceeding ten inches and weight of nearly four and one-half pounds, the turtle was indeed a genuine ‘Booner’ and was as large as Blanding’s turtles get.

Although historically abundant, Blanding’s turtles have currently fallen on hard times.  The species has become so rare, in fact, that most Iowans – even those who spend considerable time prowling the out-of-doors -- will never see so much as a single Blanding’s in their lifetimes.

Although more than a century of wetland drainage has negatively affected all of Iowa’s 13 turtle species, some of our more familiar varieties – such as painted and snapping turtles -- have managed to maintain relative abundance.  By contrast, Blanding’s turtles have been far less successful at adapting to modern-day landscapes.

The species’ low reproductive rate has contributed to the decline.  It takes 12 to 15 years -- sometimes longer -- for a female Blanding’s to produce her first clutch of eggs.  After that, a female may only produce eggs every other year.  By compari-

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