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1 <br />As in late <br />1987, there was again an apparent decrease in mean length and <br />weight in October 1988. Growth slowed appreciably in 1989; increase in <br />mean total length between late-September 1988 and late-September 1989 was <br />only 7.3 mm. <br />I Food Habits. <br />We examined the stomachs of 67 West Pond squawfish collected between 26 <br />September 1986 and 3 September 1987, while mean length of squawfish in- <br />creased from 57 to 163 mm. At least one food item was found in 31 of <br />these fish; 53.7% had empty stomachs. No stomachs contained fish. Dip- <br />tera adults and larvae were the most commonly occurring food item; chiron- <br />omid larvae disappeared from the diet after mid 1987. Mayflies and mites <br />were seasonally important (Table 3). <br />No enumeration or size-frequency analysis was made of fathead minnows in <br />West Pond, so availability of forage there is unknown. However, casual <br />observations of catch rates in seine hauls suggest that fatheads, though <br />always present, were never plentiful. In addition, extremely dense sub- <br />mersed vegetation, primarily beds of muskgrass (Chara sp.), may have <br />provided fatheads cover from squawfish predation. A seasonal abundance of <br />invertebrates or a new brood of fathead minnows might explain increases in <br />condition during late summer. Squawfish were observed rising for mayflies <br />on 29 July and 28 August 1987, and stomach analysis of squawfish collected <br />on 5 August 1987 revealed a high utilization of mayflies. Mean condition <br />(K) was higher (0.70) at this time than during other times when fish were <br />sampled that year (0.63-0.64). <br />Overall, condition of squawfish, though generally higher than that at Fish <br />Chalet Pond, was low (0.64; mean of means from Appendix Table 7) compared <br />1 22