“I never thought I’d be burning prairie to help a toad,” Felix Valdez said last spring. But that’s exactly what he was doing.


Valdez, a U.S. Forest Service fire management officer, was working with U.S. Fish and Wildlife Service managers and biologists, the multi–agency Wyoming Toad Recovery Team and other partners at Mortenson Lake National Wildlife Refuge, WY, to conserve the last known population of the Wyoming toad.


That toad, now the most endangered amphibian in North America, once flourished in the wetlands and rivers of southeastern Wyoming. By the mid–1970s, the population was in decline; in 1984, the toad was listed under the Endangered Species Act. The Nature Conservancy helped establish the refuge in 1993 to protect the species.


In April 2012, Valdez was the burn boss when a prescribed burn project to benefit the Wyoming toad formally kicked off at the refuge. The project is designed to give the native toad what it needs to survive: water and warmth.


Studies show the tiny toads require pockets of warm, shallow water to breed. Historically, the refuge used grazing to keep overgrown rushes in check, allowing plenty of sunlight to warm the waters. Over time, cattle stopped grazing thicker vegetation, which was unpalatable to them, so the refuge turned to prescribed fire. Without either grazing or recurring fire to prevent overgrowth on this high plains prairie, biologists are concerned that Wyoming toads won’t survive in the wild.


So, prescribed fire, with prescribed grazing, is part of a collaborative recovery plan to achieve self–sustaining populations and ultimately delist the species.


Experimental use of prescribed fire for the toad’s benefit at the refuge started in 2005. After that burn, the number of toads increased initially but then declined by 2010. So, the recovery team determined, via adaptive management, that fire every three or four years would best maintain quality habitat.


By early 2012, fire managers approved a plan to burn up to 23 acres. They had a limited window of opportunity—just one week in April, when the weather was right and the toads were still in hibernation. The plan, which involved Service staff from at least four states, outlined specific objectives, staff and equipment needed, and appropriate environmental conditions. Wind direction was a critical factor in timing the burn, to avoid smoke blowing into nearby wilderness or populated areas.


A Healthy Mosaic

Most of the lighting, monitoring and fire mop–up at Mortenson Lake Refuge was accomplished by seven firefighters—including engines and crews from Brown’s Park Refuge, CO, and Valdez’s home base,Medicine Bow–Routt National Forest, WY/CO. The fire cleared vegetation, created a mosaic of burned and unburned patches, and returned nutrients to the soil. Spring irrigation at the refuge then filled small shallow pools, all in time for the waking toads to start their annual call for mates.


The next burn at Mortenson Lake Refuge could occur as early as spring 2015. In the meantime, a captive–breeding program—with toad populations held at Saratoga National Fish Hatchery, WY, the University of Wyoming’s Red Buttes Biological Lab and various zoos—is contributing to the species recovery effort. To date, more than 160,000 tadpoles and toadlets have been released at the refuge and other safe–harbor sites.


Researchers continue to study the toad’s habitat requirements and the best strategies for releasing captive tadpoles and toadlets.


“Most important and exciting to me are the multiple partners working shoulder–to–shoulder,” said Mortenson Lake Refuge manager Ann Timberman “In my experience, this is the best way to deliver conservation on the ground, and the only way to get this toad recovered.”


Karen Miranda Gleason is a public affairs specialist in the Refuge System Branch of Fire Management at the National Interagency Fire Center in Boise, ID.