Nature Conservancy Protects Native

Grassland, Prairie Rattlesnake Population

Des Moines, IA—May 18, 2005—A 15-acre addition to the Broken Kettle Grasslands, Iowa’s largest contiguous native prairie, safeguards critical hibernacula for the state’s only known population of prairie rattlesnakes, The Nature Conservancy announced today. The addition to Broken Kettle, located just north of Sioux City in Plymouth County, pushes the protected acreage to nearly 3,050 acres.

“The prairie rattlesnake is one of Iowa’s last remaining ties to the extensive grasslands that once covered the Great Plains,” said Leslee Spraggins, State Director of The Nature Conservancy in Iowa. “This addition to the Broken Kettle Grasslands safeguards critical habitat for the snake and buffers the state’s largest slice of native prairie.”

Broken Kettle Grasslands is located in the northern portion of the Loess Hills, which rise 200 feet above the Missouri River Valley, snaking in a narrow band of wrinkled bluffs that cover some 650,000 acres along the state’s western border. This region supports some of Iowa’s best examples of tallgrass prairie, which originally covered 25 million acres across parts of Iowa and Minnesota. Today, less than one percent remains; making it one of North America’s most endangered ecosystems.

The extensive prairie ridgetops feature a variety of plants and animals typically found further west in the Great Plains, such as the prairie rattlesnake. Although common in South Dakota and other western states, the prairie rattlesnake is at the eastern-most edge of its range at Broken Kettle. At one time, the snakes could be found across western Iowa and west to the Missouri River. However, as native grasslands disappeared, so to did the rattlesnake, which requires large blocks of prairie as they can travel more than 5 to 6 miles from their hibernation sites. The snake measures some 35 to 45 inches long and eats a wide variety of mammals, such as rodents, birds and ground-nesting bird eggs.

“Ensuring the hibernacula is absolutely critical,” said Herpetologist Dan Fogell. “With so much of the snake’s habitat lost, protecting its hibernation site is key to a viable population.”

Broken Kettle also harbors many plant species including, lead plant, big bluestem, silky aster, ground plum, side-oats gramma, downy painted cup, nine anther dalea, purple coneflower, snow-on-the-mountain, scarlet gaura, dotted blazing star, ten-petaled mentzelia, purple locoweed, pasque flower, bur oak, tumblegrass, little bluestem, buffalo berry, scarlet globe mallow and yucca. Animal life includes the black-billed magpie, upland sandpiper, western kingbird and the Great Plains toad.