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1 1 1 1 I 1 1 Vanicek and Kramer (1969) analyzed stomach contents of 198 Colorado squaw- fish collected from the Green River. They found Cladocerans, copepods, and chironomid larvae to be the most important food items for squawfish up to 50 mm in length, but these items were not found in larger fish. Utili- zation of insects increased until squawfish were 100 mm long, after which fish became the major food item; squawfish over 200 mm long ate only fish. The smallest squawfish containing fish in their study was 50 mm TL. Our stomach analysis of 290 squawfish from Fish Chalet Pond revealed a diet composed chiefly of Cladocera,,copepods and insects; insects were primari- ly chironomid adults and larvae, corixids and spiders, with mayflies becoming seasonally important (Table 1). Most fish (74%) had at least one ' item in their stomach at the time of collection. Feeding occurred even in December, when water temperature was 3 C. Of the 215 squawfish with food, ' eight (3.7%) contained fish remains; the smallest of these squawfish was 60 mm long. Fish remains from all but one of these were identifiable by ' the Larval Fish Lab; all were fathead minnows. Piscivory increased during the second year (1987) as squawfish increased in size; on 9 July, four (91-149 mm long) of 14 (28.6%) squawfish containing food had eaten fish; one contained three fathead minnows. Cladocera remained in the diet of 1 1 t t t squawfish as large as 67 mm TL through 10 June 1987, after which this item dropped from the diet. Though piscivory increased, insects remained the dominant item in diets of squawfish longer than 100 mm. During July- September 1987, fish were found in only five of 30 squawfish (16.7%) containing food and > 100 mm long; diets consisted primarily of diptera, mayflies and corixids. Catch rates in hauls of a large seine (76 m x 1.8 m) indicated that fat- head minnows were scarce in Fish Chalet Pond. On 10 October 1986, the 11