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<br />ABsTRACT <br /> <br />The endangered Kanab ambersnail (KAS; Succineidae: Oxyloma haydeni kanabensis Pi1sbry 1948) <br />occurs in only two locations in the American Southwest: a privately-owned wet meadow at Three <br />Lakes, Utah, and a large, perennial spring calIed Vaseys Paradise (VP) in Grand Canyon National <br />Park. Believed to be relics of the Late Pleistocene glaciation, KASs are restricted to wet1and <br />habitats near limestone or sandstone cliffs. These rare landsnails are found residing and feeding <br />on cattails (Typha spp.), watercress (NOSIlIltium officinoJe), and crimson monkeyflower (MimuJus <br />cardi1lll1is). Habitat loss and incidental take by flooding are specific threats to KASs. In March <br />1996, the VP population experienced habitat loss and incidental take during an experimental <br />45,000 cfs (1275 m3/s) stage flood from Glen Canyon Dam. The Arizona Game and Fish <br />Department (AGFD) participated with an interagency monitoring team between 1995 and 1997 <br />to study the ecology of KAS and flood impacts to VP and its population. From March 1996 <br />through October 1997, habitat rwNery in the flood-impacted low zone (< 1275 m3/s stage) has <br />been slow; 10Ial area of primary and 'JI"NVlru.ry vcgelal:ion is 34.8% less than the pre-flood, March <br />1996 level. Preliminary population estimates, doived from bootstrap statistics, show an increased <br />number of KASs, indicating a return to the 1995 level of abundance. In August 1997, visible <br />sporocysts of the puasitic trematode, LeucochJoridium cyanocitule, were observed in four KASs. <br />In June 1996, AGFD began surveying and evaluating comparable habitats in Grand Canyon and <br />vicinity for establishing additional KAS populations. Currently, 74 sites have been surveyed, <br />including 57 sites documented in Sorensen and Kubly (1997). Between July and October 1997, <br />we visited 17 new sites in I1Ol'I:ht'Zn Arizona. Three sites were evaluated as "more desirable" KAS <br />habitat: one within Grand Canyon National Park (Dripping Spring) and two on the Hualapai <br />Reservation (Travertine Falls and Bridge Canyon Creek). No additional KAS populations were <br />found, but new occurrences of other mollusk species were recorded. <br /> <br />~ <br /> <br />" <br /> <br />" <br /> <br />:~ <br />::..j <br />:.~ <br />?, <br />:~.j <br />~ <br />.:~ <br /> <br />..:. <br /> <br />~... <br />" <br />~}. <br />;:~ <br />~ <br />\~.; <br />" <br /> <br />r:~. <br />.~~ . <br />';ij <br />~.:>> <br />~, <br /> <br />.< <br />