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a realistic approach to advance research and recovery of these two species. This report is presented in three chapters. The first, 'The Fish" summarizes the life histories and ecological relation- ship of the bony tail (Gila elegans) and razorback sucker (Xyrauchen texanus). The second, "Complete Life Cycle of Two Endangered Fishes at Cibola High Levee Pond" provides a description of the physical and biological attributes of the pond, a brief account of its history and management recom- mendations. The third, "Oxbow Communities: The Missing Key to Recovery?" describes the need and potential role that sanctuary communities serve in the ecology, conservation, and recovery of these and possibly other native fishes. Ecology of Bonytail and Razorback Sucker The following summaries on the life history and ecol- ogy of bony tail and razorback sucker are based on research conducted from the mid-1960's to the present. Much of the information summarized here is presented in more detail else- where. I strongly encourage readers to review these sources of information. An interactive bibliography containing more than 3,000 references for the big river fishes was developed for this project by Arizona State University (Pacey and Marsh, 200 I, 2005) and can be accessed at http://www.fort.usgs.gov/prod- ucts/pu b I icati ons/co _fishbi b/co _fi shbib.asp. Capture Techniques Bonytail Larvae Bony tail larvae are phototactic (Snyder and Meismer, 1997; Mueller and others, 2002) but have two disadvantages: they are small (6-8 mm), and hatch later in the season when predators are more active (Snyder and others, 2004). This led to a problem of detecting them in light trap samples (table 2). Sixty-four overnight (8 I 8 total hours) light trap sets yielded no bony tail larvae among numerous invertebrates. In lieu of leav- ing traps set overnight, I set four for only 2 hours and captured five bony tail larvae in three of the four traps. It is possible that overnight sets experience in-trap predation by odonate nymphs. I was unable to test that theory. Larger Bony tail Techniques used to capture bony tail have remained unchanged for centuries. Local tribes used dip nets, seines, fish traps, and fashioned hooks (Wallace, 1955; Stewart, 1957). Archaeologists have reported the rock remains of hundreds of fish traps found along the ancient shoreline of Lake Cahuilla, the enhanced version of the Salton Sea (fig. 8). The Fish 9 Table 2. Catch rate of bonytaillarvae and invertebrate taxa cap- tured in light traps set in Cibola High Levee Pond in 2002. Sixty trap sets were left overnight; four were removed after 2 hours. Organism Average per seta Bony tail (traps set overnight) Bony tail (traps set for 2 hours) Dragonfly nymphs (Anisoptera) Mayfly nymphs (Ephemeroptera) Damselfly nymphs (Zygoptera) Scuds (Amphipoda) Water boatman (Hemiptera) 'n =64. 0.00 1.25 1.25 5.99 10.99 88.98 302.94 The structures date back to 700 A.D. and many were found to contain bony tail and razorback sucker bones (Schaefer, 1986). Historically, bony tail was one of the most easily caught fish in the river basin and have been taken by hook-and-Iine on baits that include worms, cheese, dough balls, and lettuce (Blake, 1864; Sleznick, NPS-retired, oral commun., 200 I). Hatchery-produced bony tail have recently been taken by anglers in both Lake Mohave and Lake Havasu (Mueller and Marsh, 2002; Kirk Koch, BLM, oral commun., 2004). Hatch- ery personnel report they are easily taken on artificial flies. Biological surveys, on the other hand, have relied heav- ily on the use of trammel nets and electrofishing. Recently, the use of electroshocking has become controversial due to reported hemorrhaging and spinal damage (Snyder, 2003). Ruppert and Muth (1997) reported a high incidence of internal hemorrhaging in young bony tail and razorback sucker. How- Fig. 8. Photograph of an ancient rock fish trap located near the Salton Sea, California. Photo courtesy of Eric White, Bureau of Reclamation.