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Arizona Game and Fish Department NGTR 125: Kanab Ambersnail Report April 1998 Page 10 HABITAT SURVEYS To consider downlisting KAS to threatened status, the Kanab Ambersnail Recovery Plan (USFWS 1995) requires the provision of finding and/or eslablishing 10 separate populations of KASs which have demonstrated long-term viability in abundance, distribution, and stability. This criterion includes the establishment of fonnalland management designations and/or implementing land management plans for undisturbed, long-term KAS habitat. Conservation of existing KAS populations and habitat must be regulated through sections 6, 7, and 9 of the Endangered Species Act. Establishment of new wild KAS populations will require moving a number of KASs (including snail egg masses) from VP and/or 3L to other suitable habitat. Snails for relocation should be removed from these sites during mid- to late summer as peak reproduction occurs and population numbers are greatest. However, if high flow releases (emergency floods or scheduled habitat- building/maintenance flows >33,000 cfs [934 m'/s] stage discharge) from Glen Canyon Dam occur with anticipated loss of KASs and VP habitat, all efforts should be made to transplant imperiled KASs. Relocated snails should be examined for Leucochloridiwn parasites. This trematode typically expresses visible sporocysts in mature, infected KASs during the late summer months (Stevens et al. 1997a, 1997b). Unfortunately, young snails and egg masses are more difficult to screen for parasite infestation. There are several actions available to aid the recovery or enhancement of KAS. New KAS populations can be established in the following scenarios in order of preference: 1) Using existing natural habitats (unmodified) that are evaluated as having highly comparable biological, chemical, and physical characteristics to the VP and 3L sites. "Keyhole Spring," Roaring Spring, and Thunder River are examples of optimum KAS habitat. Saddle Canyon, Upper and Lower Deer Creek springs, 147.8 mi RR Seep, Travertine FaIls, Bridge Canyon Creek, Dripping Spring, Santa Maria Spring, Lower Ribbon FaIls, Showerbath Spring, and Canyon Creek Spring are existing natural habitats that are ranked second best for establishment sites. 2) Establishing refugium populations of KAS in academic research facilities and/or zoological gardens as supplemental genetic sources. This option requires the propagation of host vegetation in environmentally-rontrolled terraria. It is the opinion of the KA WG that refugium populations may be equivalent of IO(j) status and would benefit the species, but not contribute to downlisting. 3) New KAS populations may be found with additional habitat surveys of other locations in Grand Canyon, northern Arizona, southern Utah, and Arizona tribal lands. .