U.S. DEPARTMENT OF THE INTERIORBUREAU OF LAND MANAGEMENT
|Fish, Wildlife, and Plant Conservation|
Species recovery starts with one or more inventories to determine a species presence or absence on public lands. Where species are present, the BLM actively engages in planning for its recovery. BLM field biologists and managers may serve on interagency recovery teams. On the ground, BLM then focuses resources on implementing actions in the recovery plan Recovery actions may include monitoring of populations, restoring or maintaining suitable habitat, conducting research to understand and address threats to the species, and participating in efforts to establish new populations. As of 2010, the BLM is participating in the implementation of more than 1,600 actions identified in recovery plans, including restoration or enhancement of more than 30,000 acres of habitat for the direct benefit of listed species.
Case Study: Recovery in Action
BLM Biologist's "Head Start" Program Enhances Populations of Threatened Chiracahua Leopard Frog
The BLM is actively participating in recovery actions for the threatened Chiracahua Frog, listed as a threatened species in 2002. The 2007 recovery plan calls for establishing "refugia" of backup populations of frogs to help protect the genetic diversity of isolated populations. This entails capturing tadpoles and frogs in the wild and rearing them in artificial habitats.
Young tadpoles are most vulnerable to predation, flood, and other environmental influences. Therefore, short term refugia (i.e. ponds) are used as “head start” sources to ensure the tadpoles survive to a breeding age, at which time they may be transplanted to a more long term refugium or back into the habitat from which they were captured.
Any manipulation of a listed species requires a special permit from the U.S. Fish and Wildlife Service (FWS) or National Oceanic and Atmospheric Administration – Fisheries. (See "Don't Do This At Home," below.)
That is why Jack Barnitz, a wildlife biologist for the BLM's Las Cruces, New Mexico, District, obtained a permit. Wanting to do more for the species, in 2009 he established a “refugium” for the listed frog. This is very labor intensive. The artificial habitat must be maintained within stringent guidelines established by the FWS and listed in the frog's Recovery Plan.
To get started, he captured tadpoles and juvenile frogs from two source populations, then reared and raised them to adulthood in two water troughs engineered as artificial ponds. He tested them for Chitrid fungus and treated them as necessary, following accepted guidelines.
Frogs from one population were transported to the long-term Fortworth Zoo ranarium and breeding facility. Frogs from the second population went to a long-term refugium established on the USDA-Agriculture Research Station, Jornada Experimental Range (JER) in Las Cruces.
The JER agreed to become a cooperator in the Chiracahua leopard frog recovery effort by allowing the modification and use of their large open topped water storage tanks. If these refugia become successful in sustaining breeding populations, they will become a source of healthy, disease free frogs to augment populations and/or reestablish them back into historic habitats (public, private, or state lands). The JER agreement can provide up to four (and possibly more) different refugia.
The US Forest Serivce, the Turner Endangered Species Fund, and others are also conducting captive rearing programs and have established long term refugia, using livestock water storage tanks similar to what BLM is doing in cooperation with the JER.
Barnitz is currently maintaining a small number of adult frogs from one distinct population in his refugium. He is hopeful that these adults will breed and provide additional individuals for placement in refugia or into native habitat.
Don’t Do This At Home!
The southwestern willow flycatcher (Empidonax traillii extimus) is an endangered bird that inhabits riparian habitats in six southwestern states. Federally-listed in 1995, it also is recognized as endangered by the State of New Mexico. Declining populations are attributed in part to habitat loss and degradation.
The southwestern willow flycatcher requires dense riparian habitat for nesting. The birds spend the summer, and nest, in the southwestern U.S. They winter in Central America. In 2005, the U.S. Fish and Wildlife Service (FWS) designated approximately 737 miles of critical habitat for the species in five states, including New Mexico. Most of the species’ known breeding territories in New Mexico occur in the southwestern part of the state, along the Gila River in the Gila/Cliff area and further downstream in the vicinity of the Gila Lower Box near the Arizona border. This includes riparian habitat managed by the BLM.
In 1990, the BLM’s Las Cruces Field Office, in cooperation with two grazing permittees, excluded livestock grazing from approximately 6.5 miles (400 acres) of the Gila River riparian corridor known as the Gila Lower Box in western New Mexico. The exclosure project was initiated to achieve riparian habitat management goals; at that time, the flycatcher was not listed. The photo pairs in this article show the difference in riparian vegetation after some years. Above and left are photos of the Dixon Fence area taken in 2002 and in 2009. The photos below right were taken in the downstream area of Lower Box in 1995 and in 2009.
In cooperation with the permittees, the BLM built exclosure fences to restrict livestock grazing within the riparian area and provided livestock waters outside of the riparian area. With the exception of two gap fences crossing the river, the permittees have maintenance responsibility for the upland fences and livestock waters.
Riparian conditions have improved dramatically since the riparian exclosure fence was constructed. From 1993 to the early 2000’s, available flycatcher habitat along the Gila Lower Box riparian corridor was limited to only a few suitable patches. Habitat has since improved to provide continuously suitable habitat along the entire corridor.
Another problem for the flycatcher is parasitism. Female cowbirds lay their eggs in flycatcher nests; their hatchlings can kill young flycatchers. Since cowbirds are associated with cattle, altering grazing regimes not only can improve riparian habitat, but it can also reduce cowbird parasitism.
The BLM Las Cruces Field Office has been conducting breeding surveys for southwestern flycatchers since 1993. Following FWS protocol, they are conducted from the middle of May until nesting is completed in summer. The field office completed surveys in 1993, 1996 – 2005, and 2007– 2008. Since the surveys began, southwestern flycatcher population estimates and the number of breeding sites have greatly increased. Breeding surveys indicate that in 1993, one nest and 7 birds were counted in the lower Gila River, New Mexico, area; in 2008, 130 nests and about 260 birds were counted in the same area. The dramatic improvement in flycatcher territories no doubt has contributed to the increased number of nests and birds observed during the breeding season. (Improved survey methods may account for some of the increase.)
The Gila Lower Box is primarily native cottonwood/willow habitat. The presence of invasive salt cedar is limited. However, the BLM Las Cruces Field Office monitors salt cedar densities with plans for future treatments if needed. The Field Office continues to monitor other changes in riparian condition throughout the Gila Lower Box as well.
photos at left: Fisherman's Point, taken in 1992 and in 2009.