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I <br /> <br />and then weighing the entire group, a total of 2,440 fish in the school <br />was estimated. We do not know whether this school represented the majori- <br />ty of the surviving population or not. However, at least 34.9% of the <br />7,000 squawfish had survived 10 months since stocking. In the corner of <br />the pond that we could routinely seine, catch rates dropped off in late <br />September 1987, perhaps due to the fish redistributing themselves as <br />I temperature or food supply changed. In mid April of the following year we <br />were again unable to seine any squawfish from that portion of the pond. <br />However, in mid June the fish reappeared there and we captured 71 with one <br />seine haul. Subsequently, we found angling to be the most efficient <br />method of sampling at West Pond, and through fall of 1987 we could readily <br />catch a sample of 20-30 squawfish in a short time. When the pond was <br />rotenoned in September 1989, 330 squawfish were recovered, representing a <br />survival rate of 4.7% over a 3-yr period. <br />Predation. There were no predacious fish in West Pond, other than the <br />stocked squawfish themselves. Cannibalism was probably not an important <br />factor affecting squawfish survival. Though forage was limited, size <br />variation among squawfish was probably not great enough to allow the <br />largest squawfish to eat the smallest (Appendix; Table 7). <br />Disease. Squawfish in West Pond became infected with Asian tapeworm. The <br />pond was inadvertently inoculated with this cestode when fathead minnows <br />were transferred there from neighboring T & F Pond during 1986. Minnows <br />in T & F Pond apparently became infected in 1983 when parasitized squaw- <br />fish from Dexter NFH were stocked. All the squawfish in T & F Pond even- <br />tually died from undetermined causes, but the other species of fish that <br />remained there were sampled and determined to be worm-free by the Fort <br />' 26