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Arizona Game and Fish Department Draft EA: Kanab Ambersnail June 1998 Page 12 habitat. The base of the spring may be affected by natural disturbance (flash floods down Nankoweap Creek), Limited amount of primary vegetation could only support a small KAS population, This site is accessed by a 4-mile (6.4 km) hike from the river corridor. Sites 13-15 may require planting additional host vegetation, diversion or retention of water, and/or construction of flood control barriers to be more suitable for KAS populations, C, TIMING OF THE PROPOSED ACTION Considerations for timing of proposed translocations ofKAS include proposed BHBFs, the period of reproductive activity, availability of different life stages, and winter dormancy, The most opportune times to translocate KASs may well be compromised by BHBFs, Those KASs living in the lower vegetation zone ofVP are likely to be inundated by a BHBF, and will probably be swept downstream and perish, KASs living in the habitat below the BHBF's stage discharge elevation should be removed prior to the flood, and can be used for translocations, This is an important consideration in reducing the incidental take for VP KASs and providing a founding stock that would have been lost anyways, Most KASs at VP secrete a mucoid plug (epiphragm) to close the foot opening in the shell and overwinter on rock surfaces or dry plant material in a dormant state, Transition to the overwintering state typically begins in October, Overwinter mortality can be quite high, in some years >50% of the autumn population, We consider the period of overwintering, November-February to be generally unsuitable for moving KASs unless some factor, such as a BHBF during this period, will cause losses of individuals that could be moved, Most KASs that successfully overwinter are immatures; individuals that reached adulthood in the previous year typically perish during this period, From March through May, KASs are growing and amassing energy stores to be used in reproduction, There are relatively few adults or individuals <5 mm in length available during much of this period, Movement of pre-reproductive individuals to new sites during spring months would allow for production of progeny in the new site during the normal reproductive period of May-August. Individuals produced at the new site can then grow and enter the period of overwintering at that site, The only drawback to this scenario is that individuals may be moved who harbor the trematode parasite, Leucochloridium. The parasite is not expressed (visible) until KASs reach lengths of>13 mm, From June through September, all size classes of KASs, including eggs, are available for translocation, Movement of reproductive age individuals becomes increasingly less suitable as this period progresses, because these individuals have little chance of surviving the winter at the new site, Any transfer of adult KASs risks the movement of individuals infected with the parasite Leucochloridium, Movement of egg masses has been tried on one occasion, Twelve egg masses were transported from VP to NAU in August 1997, Researchers involved in the transport did not isolate