Preservation By David Blacker, Executive Director From the Director DVNHA One of the biggest highlights of visiting Death Valley National Park or Ash Meadows National Wildlife Refuge is seeing and maybe getting a photo of a desert bighorn sheep. You see the desert bighorn in our logo, a strong and majestic animal with iconic large curling horns, but your chance of seeing one of these incredible creatures is shrinking. Surprisingly the biggest reason is not climate change, but the spread of an invasive species that dominates and destroys their water sources and bullies them out of their historic range. In the economic downturn of the early 2000s, people stopped adopting burros and the Bureau of Land Management (BLM) pens filled up. A growing unchecked burro population began to grow and spread. I began to hear reports of sightings in Panamint Valley and the Nevada Triangle back in 2005. Now there are herds occupying Butte Valley, Skidoo, Wildrose, and southern areas of the park. Everywhere burros appear, the impact is predictable. First they seize control of the local water source, trampling or eating the native vegetation. Being very territorial, they use their size and aggressive nature to chase off any competition. Once burros move into a water source, bighorn sheep will not use it. Our partners at NPS are working diligently to reduce and remove invasive burros from the park. They have partnered with Peaceful Valley Donkey Rescue to roundup and adopt out burros from Death Valley. Burro numbers increase by 20-30% a year, so more than 750 burros need to be rounded up annually to stay ahead of reproduction. NPS is also fencing off some of the bigger springs to keep burros out. The special fencing allows bighorn sheep to slide under the fence and deer to jump over—keeping out the burros, but this is only practical at the larger springs. Controlling the population using birth control is not an option due to cost and difficulty. In my opinion, unless roundups and fencing can become much more effective, the only option will be direct reduction. Now before you start sending me irate e-mails, the park is not close to this decision yet and if all the burro loving population will begin adopting, maybe we can get ahead of this. If not, we are only talking about Death Valley National Park. Wild burros will continue to be plentiful on BLM land all over the Mojave Desert. Death Valley National Park was created to not just protect the scenery or history, but to be a safe place for the native animals to live the way nature intended. We should not let misplaced affection to allow its destruction. Long live the desert Volume 66 bighorn! Issue 1 A group of invasive burros in Butte Valley, where a great deal of resource Winter 2021 damage has been done. Photo courtesy of NPS, W. Sloan T ELESCOPE death valley natural history association dvnha.org By William Sloan, Wildlife Biologist Invasive Burros in Death Valley National Park National Park Service, Death Valley National Park Wild donkeys (Equus asinus), also known as burros (from Spanish, “borrico”), are native to west Africa. Burros were imported and used as sturdy stock animals by early miners and explorers in the 1800s throughout the American West. Escaped and abandoned animals quickly established numerous feral herds on public lands. Although frequently seen as cute, adaptable, and intelligent, burros multiply quickly, denude federal lands of native vegetation, and compete with native wildlife for limited water and forage. Viewed by horse and burro advocates as symbols of the Wild West, these animals were given federal protection by the Wild Free-Roaming Horses and Burro Act in 1971, which protects burros on Bureau of Land Management (BLM) and U. S. Forest Service lands but not National Park Service (NPS) lands where they are managed as non-native animals. Currently, herds on BLM lands nationwide consist of an estimated 96,000 horses and burros, which greatly exceeds the approximately 27,000 Above: A spring trampled and fouled by invasive burros. specified as the “appropriate management level.” Without Below: Native vegetation damaged by invasive burro browsing. natural population control from predation and disease, Photos courtesy of NPS, W. Sloan burro populations increase at an annual rate of 20-30% if left unmanaged. Burro populations cause extensive damage to native vegetation and spring ecosystems and compete with native wildlife, such as bighorn sheep and desert tortoise, for limited resources. Burros are aggressive animals that defend their territory, preventing native animals from using the few vital water sources in arid desert regions. One burro consumes approximately three tons of forage per year (about 17 pounds per day). Slow-growing arid lands quickly became degraded, which leads to serious erosion—loss of up to 76 tons of soil per square mile per year has been documented on lands damaged by burros. Besides out-competing native plant-eaters, fouling springs, and damaging vegetation, burro foraging reduces the amount of seeds available, affecting bird populations as well. Death Valley National Park is facing growing issues with damage to fragile spring ecosystems and impacts to native vegetation and wildlife from increasing populations of non-native burros on Fertility control is not a viable option because it would require park lands. Burros were eliminated from much of Death Valley administering contraceptive drugs to each burro at least every through direct reduction in the 1940s and in the 1980s. Burro two years within the vast and rugged park terrain. Fencing captures in 2005 reduced the population to less than 400, but the border of the 3,400,000-acre park is not practical, and the burro population has continued to grow since then. Burros burros will always be present on surrounding lands. The park are now in areas that were previously burro-free for decades. In is currently planning to fence a number of springs in order to 2018 the park signed an agreement with the privately-funded reduce damage to sensitive spring habitats, reduce competition nonprofit Peaceful Valley Donkey Rescue to capture and find with native wildlife, and reduce the dispersal of burros into adoptive homes for park burros. Peaceful Valley has removed new areas. The park is also working with adjacent BLM field 191 in the past three years out of an estimated population of offices to coordinate burro round-ups along border areas to around 4,000. reduce encroachment into the park. The park will continue to apply current science and best management practices to The park is continuing to look for solutions to reduce the reduce burro populations in accordance with the park’s general number of burros in the park and their subsequent impacts. management plan. 2 dvnha.org death valley natural history association T ELESCOPE By Michael Reeves, Fish and Wildlife Biologist Not Always the Big Things U. S. Fish and Wildlife Service, Ash Meadows NWR Ash Meadows National Wildlife Refuge brings up different memories for different people depending on what they ex- perienced while visiting. After all, it is an oasis in the desert. Ash Meadows is home to at least 26 endemic species of plants and animals that occur nowhere else in the world! Our playful pupfish are part of that group. Ash Meadows also has upwards of 30 springs, some easier to find than others. You TELESCOPE might not realize that some more sinister creatures also call Volume 66, Issue 1 Ash Meadows home. These specific flora and fauna are re- ferred to as invasive species. Who We Are: Most of the invasive plants and animals of Ash Meadows threaten the success of our endemic flora and fauna. Several Executive Committee aquatic invasive animals threaten our native pupfish, dace Kimber Moore Board Chair and spring snails. Some of the more detrimental to the ref- uge are the red swamp crayfish (Procambarus clarkii), green Nathan Francis sunfish (Lepomis cyanellus), largemouth bass (Micropterus Board Vice-Chair salmoides) and the American bullfrog (Lithobates catesbe- Terry Feinberg ianus). Some of these species are more threatening to the Treasurer Above: Large, invasive salt-cedar compete for endemic species that inhabit our springs than others, but the William Walton scarce resources on Ash Meadows National theme is consistent. They all compete for resources needed Secretary Wildlife Refuge. for the survival of our endemic species or they impact the Board Members Below: Adult red-swamp crayfish invade species directly by eating them or their young. Regardless spring systems feeding on threatened and Wynne Benti endangered fish and their larvae. of their strategy, aquatic invasive species undoubtedly harm John Kopczynski Photos courtesy of Rod Colvin, USFWS. the native spring ecosystem. Bob Lehmann Tom Moritz We also have invasive plants that are sometimes overlooked Dan O’Brien as detrimental to refuge resources. The two most noticeable Administrative Staff are tamarisk (Tamarix spp.) and common reed (Phragmites David Blacker australis). Tamarisk is generally found in our riparian zones Executive Director whereas the common reed is usually found in our marshes. Sandra Andrus-Sheet Either way, both are extremely adapted to surviving at Ash Office Manager/Accounts Receivable Meadows, making both mechanical and chemical removal Geneil White very difficult. They can shade or choke out the sunlight and Telescope Editor outcompete our native plants for resources. They are adapt- ed to fire, meaning removal by fire doesn’t really do much to Danielle Wood Development Specialist/Memberships extirpate them. Both are very well established on the refuge and many hours every year are devoted to restoring native Renee Rusler plants to their rightful place. Field Institute Director One of Ash Meadows biggest invasive removal efforts was Warehouse Wesley Massey, Warehouse Manager that of eradicating crayfish from the Warm Springs Complex Bill Pelkey (WSC), one of the only successful crayfish eradications in the country, an effort that took seven years, countless hours of Bookstore labor and the help of taxpayer dollars.