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' number of fathead minnows in one seine haul was only 7.7% that of squaw- fish; the number of carp was about double that of squawfish (n = 1739 fish sampled). However, most of these carp were too large to be available as food for squawfish. Bulkley and Berry (1985) found that mouth width ' limited the size of rainbow trout (Oncorhynchus mykiss) that Colorado squawfish could consume and that mouth width roughly equaled 10% of squaw- fish body length. Frequencies of body depths of carp collected from Fish Chalet Pond on 10 November 1986 (n - 25) were compared with frequencies of ' mouth widths of squawfish (estimated from total body-length measurements). Assuming that carp with body depths greater than the mouth width of squaw- f ish were unavailable as food, we estimated that 40% of the squawfish had ' no carp available, 55% of squawfish had only 8% of the carp available to them, and only 5% of squawfish had 28% of the carp available (Table 2). Thus fish forage was limited for stocked squawfish; the availability of invertebrates was not estimated. On 9 July 1987, body-depth frequencies of carp and fathead minnows were ' again compared with frequencies of estimated squawfish mouth widths (Table 2). Apparently, the only carp present were yearlings from the 1986 co- hort, we detected no YOY carp. No forage fish were available for 32% of ' the squawfish; 48% of the squawfish had only 7.5% of the carp and no fatheads available; 5% had 7.5% of the carp and 15% of the fatheads avail- able; the remaining 16% of the squawfish were capable of preying on vary- ' ing proportions of the two forage species. Thus prey fish were probably scarce for all but the largest squawfish; smaller squawfish may have had 1 only invertebrate foods available to them. 1 14