2008-06-12_GENERAL DOCUMENTS - C1980007 (3)

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of wildlife highway mortality- and mitigation in North America. ERO Resources (2001) and the Service (2003a) used these traffic volume thresholds for the U.S. Hlahway 160 East Improvements project biological assessment and biological opinion number ES!LK-6-CO-03-F-022. respectively. Gibeau and Heuer (1996), recorded 7 (47 percent) aborted crossing attempts out of 15 total attempts made by lynx along a road they state has a traffic volume as high as 4.000 VPD. More recently. Alexander et al. (2004) corroborated the above relative numbers in a study examining hiahway traffic volumes on habitat permeability of six carnivore (including lynx per N. Warren. Forest Service. pers. comm., November 18, 2004) and four ungulate species in the Canadian Rocky Mountains.. Alexander et al. (2004) found that hither traffic volumes sit.:nificantly (P<0.05 reduced habitat permeability for carnivore and ungulate guilds and both guilds combined. Landscape level permeability was significantly impaired for carnivores at moderate traffic volume (5,000-5,000 VPD) and they recommended that mitigation should be implemented at these highway volumes to restore o- maintain habitat connectivity (Alexander et al. 2004; N. Warren, Forest Service, pers. comm., November 18, 2004). Movement and dispersal corridors should be several miles wide with only narrow -aps. Large tracts of continuous coniferous forest are the most desirable for Canada lynx travel and dispersal (Tanimoto 1998). The Service (58 FR 16052-16086, 68 FR 40076-40101) found that lynx are impacted by high traffic volume on roads that bisect suitable lynx habitat and by associated suburban developments. The finding detennined that the impact of high traffic volume was low except in the Southern Rockies ecosystem. s Colorado Population Size The CDOW initiated a lynx reintroduction program in February 1999. The program augmented • any existing population with transplants from Canada and Alaska, with the intent of reestablishing viable, self-sustaining populations in primary blocks of suitable habitat throughout the Southern Rocky Mountains. Ninety-six lynx were released into the San Juan Mountains during the winter/spring periods of 1999 and 2000 by the CDOW. No releases took place in 2001 or 2002. In 2003, 33 additional lvnx were released into south-central Colorado as part of the State's recovery program. In April of 2004, 37 lynx were release into the States "core" area., and 38 lynx were released in 2005, with releases planned in subsequent years. In May and June of 2003, the State of Colorado confirmed the birth of 16 lynx kittens. Evidence of reproduction and multiple individuals within each litter suggests that there is an adequate local supply of prey. CDOW confu ned reproduction in 2004, consisting of the birth of 30 kittens to 1 1 females and in 2005, 16 dens was visited and a total of 46 kittens were found. Seventeen of the 2004 cohort are known or presumed dead and the status of 4 is unknown. The remaining 18 were all tracked during the winter of 2004-2005. Some of the lynx initially released by the CDOW appear to have established home ranges, as demonstrated by radio telemetry (Tanya Shenk, pers comm. 2001) N'lanv of the released ]vnx have displayed fidelity to areas awav from the release areas su(--,estin,-, that they have sought these areas out. and sufficient prey exists to support them. Most of these lynx are currently known to occupy the San Juan Mountains. A number of lynx have made and continue to make exploratory movements throughout the Southern Rockies. Several animals have taken up residence for extended periods in the central and northern mountains. Cun-ently. 1_,,n-.\ exist in most major portions of the Southem Rockies Ecosystem. i5