UW Research and Collections Contribute to Delisting of Plant

Research by University of Wyoming scientists has contributed to the removal of federal protection for a plant found in southeast Wyoming, northern Colorado and western Nebraska.

The Wyoming Natural Diversity Database (WYNDD) at UW has led monitoring of the Colorado butterfly plant (Oenothera coloradensis) -- listed in 2000 as threatened under the Endangered Species Act -- at F.E. Warren Air Force Base near Cheyenne. In 2018, WYNDD scientists heralded a new peak in population numbers at F.E. Warren, where almost 15,000 Colorado butterfly plants were tallied, the highest total in 32 years of monitoring.

The U.S. Fish and Wildlife Service followed suit in monitoring other populations -- with landowners’ permission -- and concluded that the Colorado butterfly plant has healthy vital signs and has recovered, despite the threats identified in 2000 when it was listed.

The Colorado butterfly plant is restricted to wet meadows, with its center of distribution in Laramie County and nearby areas of Colorado and Nebraska.

Earlier this month, the Fish and Wildlife Service announced its decision to delist the plant: www.federalregister.gov/documents/2019/11/05/2019-24124/endangered-and-threatened-wildlife-and-plants-removing-oenothera-coloradensis-colorado-butterfly. The rule goes into effect Dec. 5.

On that day, UW researchers, landowners and agency biologists will gather at the Fish and Wildlife Service’s Ecological Services Field Office in Cheyenne to recognize the species’ recovery partnerships.

WYNDD’s Colorado butterfly plant monitoring at F.E. Warren has been a collaboration with federal partners and many students over the years.

The Colorado butterfly plant is restricted to wet meadows, with its center of distribution in Laramie County and nearby areas of Colorado and Nebraska. (Bonnie Heidel Photo)