Agriculture and Ranching. Agriculture and ranching activities can result in habitat loss and fragmentation, depending on range management practices, stocking densities, and infrastructure. Shinnery oak, an essential element of DSL Habitat, was historically cleared for agriculture and to increase forage for grazing. In 1974, the herbicide tebuthiuron was introduced to control shinnery oak. Historically, shinnery oak is estimated to have covered 405,000 ha in Oklahoma, 607,000 ha in New Mexico, and 1.4 million ha in Texas (Xxxxxxxx and Xxxx, 1998). By 1994, an estimated 130,000 and 40,000 ha of shinnery oak in Texas and New Mexico, respectively, had been treated with the herbicide (Xxxxxxx and Xxxxxxxx, 1996). The effectiveness of tebuthiuron applications varies, but a 95 percent reduction in oak cover has been documented with as low as a 0.4kg/ha application rate (Xxxxx and Xxxxxx 1984). The reduction in shinnery oak cover is reflected in DSL populations – areas experience drastic reductions and extirpations following herbicide treatment (Xxxxx et al., 1997) Herbicide application by agricultural and ranching interests, particularly tebuthiuron, can kill shinnery oak. The loss of shinnery oak has been correlated with reductions in DSL abundance (Xxxxx et al., 1997). Top-kill of shinnery oak due to mechanical removal or fire often triggers rigorous resprouting within a year of disturbance, pending favorable conditions. Persistent drought may delay regrowth, leaving the surface habitat exposed to significant wind erosion before conditions enable resprouting to occur (Xxxxxx et al., 1989; Xxxxxx 2006 and Cox et al. 2012). While tebuthiuron demonstrates low toxicity to fish and wildlife, it persists in the environment in soils and vegetation. Chemical decomposition varies with climate and soil conditions. Half-life ranges between 11 and 61 months (Xxxxxxxx 1985). In the arid southwestern United States, decomposition in the natural environment was estimated to occur between three and seven years. In Texas, tebuthiuron persisted in the Claypan Resource Area for more than two years (Xxxxx et al., 1982). Furthermore, chemical recycling via absorbing and decaying vegetation may prolong the presence of tebuthiuron in the environment. One study detected the herbicide in the environment via contaminated plant tissues over 11 years after initial application (Xxxxxxx and Xxxxxx, 1991). The herbicide is most commonly applied in pellet form by air. The 2020 DSL CCAA prohibits herbicide application...
Agriculture and Ranching. The Implementation Committee, with input from ranching industry participants, will develop a grazing plan for areas near designated Life History Sites or Sensitive Habitat Areas, subject to approval by the Executive Committee. The Implementation Committee will also develop a Vegetation Plan to incrementally remove invasive species (Creosotebush, Xxxxxx tridentate; Honey Mesquite, Prosopis glandulosa; Saltcedar, Tamarix spp.; Russian Olive, Elaeagnus angustifolia; and Tarbush, Flourensia cernua) and replant with native grasses, trees, or shrubs. The Agriculture and Ranching Participants (Agriculture and Ranching Participants) shall implement the following Conservation Measures, as set forth in greater detail in each CI, to minimize adverse effects on Covered Species: Zone A:
Agriculture and Ranching. The original calculation of habitat loss for agricultural activities in the 2012 TCP limited the losses over 30 years to 1,087 acres or approximately 0.5 percent of total habitat loss, which the TCP characterized as “minimal.” (See TCP at 60; See also 77 Fed. Reg. at 36,892.) As reflected in the 2012 TCP Take analysis, grazing and other agricultural activities historically have not resulted in significant habitat loss. (See 77 Fed. Reg. at 36,892.) CPA had no record of any ranching and agricultural disturbances. The 2020 DSL CCAA restricts the creation of New Surface Disturbances by Agriculture and Ranching Participants in High and Intermediate Suitability areas of DSL Habitat. In addition, grazing activities must be conducted as prescribed by NRCS Code 528. Further, the more stringent restrictions in this 2020 DSL CCAA on tebuthiuron use should markedly limit the loss of shinnery oak associated with dune complexes caused by use of the herbicide. Similarly, restrictions on new fencing in High and Intermediate areas of DSL Habitat should also minimize the threat of predation. Accordingly, we anticipate Take associated with agricultural and ranching activities to be minimal and not greater than the 1,087 acres projected in the TCP. The estimated range-wide take allocation for this covered activity is presented based upon forecasted future covered activities under this plan and under the TCP.
