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<br />Arizona Game and Fish Department <br />Draft EA: Kanab Ambersnail <br /> <br />June 1998 <br />Page 20 <br /> <br />masses (Sorensen and Kubly 1998), One KAS, with two sporocysts, was later dissected, The <br />reproductive tract was reported to be intact, even with the presence of the 12 mm-Iong sporocysts <br />(pers, comm, 1. Hoffman), Parasite infection of the KAS population at VP is low (<10% total <br />population 1995-1997 [Stevens et ai, 1997a, 1997b; IKAMT 1998]), and likely has evolved naturally <br />with this population, <br /> <br />Relocated KASs, infected with the parasite are unlikely to contaminate existing mollusk populations <br />at proposed establislunent sites, Baer ( 1971) reports that the genus Leucochloridium may parasitize <br />many species of passerine birds (definitive hosts), but always selects Succinea spp, (in the same family <br />as Oxyloma and Catiflel/a) as the molluscan intermediate host. However, KAS investigators have <br />not observed this parasite in other molluscan species at VP or other locations throughout Grand <br />Canyon and vicinity, Likewise, AGFD has not found any scientific literature on other landsnails, <br />aquatic snails, or slugs as being intermediate hosts for the genus Leucochloridium, Currently, there <br />is no scientific evidence that the native parasite L. cyanocittae is detrimental to KASs at the <br />population level, or to any other landsnails in the Grand Canyon region, <br /> <br />The risk of Leucochloridium infecting new KAS populations is present regardless of transport <br />method or founder stock. Certain precautions can be taken to reduce the occurrence of this parasite <br />in new KAS populations, Mature KASs (>13 rom in size) can be examined for visible sporocysts, <br />One method for screening trematode parasites requires moving KASs into a sterile holding facility <br />to raise new progeny, Propagation is a time and effort-intensive process requiring environmentally- <br />controlled enclosures, acquisition and maintenance of host vegetation and mollusks, necessary state <br />and federal permits, and compliance with the draft USFWS captive-breeding policy and American <br />Zoo and Aquarium Association Species Survival Plan (SSP) guidelines, <br /> <br />TPZ is well equipped to handle a large, long-term population ofKASs as a refugium, However, a <br />June 1998 memo from their KAS refugium manager (M, Demlong) cautions that a significant change <br />in their role (from refugium to rearing KASs for reintroduction) may force them to withdraw their <br />participation, Demlong cites several reasons that currently prevent TPZ from propagating KASs for <br />reintroduction stock: lack of additional funding and available staff (rearing efforts are 10 times more <br />labor intensive); expensive refugium enclosures have already been built, and were not designed to <br />propagate large numbers of snails; TPZ would need legal clarification of their requirements under the <br />draft USFWS captive-breeding policy; and the September 1998 moratorium on establishing new <br />studbooks or SSPs, <br /> <br />There is no 100"10 guarantee that new KAS populations will be parasite-free, even using captive-bred <br />stock, Passerine birds that range throughout the Grand Canyon region can infect new KAS <br />populations after establislunent. In addition, Baer (1951) reports that the encysted metacercaria <br />(minute, larval stage) of Leucochloridium can be directly passed by infected mollusks to the <br />surrounding vegetation, Other KASs grazing on this vegetation may ingest the expelled metacercaria <br />and become infected, Moving egg masses from VP would require moving a small amount of <br />