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Ou203? The fecundity of seven females from Island Lake (Type B), averaging 270+mm in length, had a mean value of 299 eggs per fish (Nelson 1972). Como Creek greenbacks (Type A) held at the USFWS Fish Technology Center (FTC) at Bozeman, Montana, produced 1.5 eggs per gram of female weight for 2-year-old greenbacks weighing 254 grams, and 1.4 eggs per gram of female weight for 3-year-olds weighing 357 grams (Dwyer 1981). In the Big Thompson River (Forest Canyon), RMNP at an elevation of approximately 3,200 m, Bulkley (1959) observed slightly hybridized (Type B) greenback fry emerging on August 26. Food and FeedinQ Jordan (1891) mentioned that Q. g. stomias fed on invertebrates when held in the Leadville NFH, but were reluctant to accept fish flesh as food. Bulkley (1959) reported that the elightly hybridized greenbacke in Forest Canyon, RHNP (3,200 m), fed upon terreetrial organisms during the summer, primarily adult Hymenoptera and adult Diptera. Fausch and Cummings (1986) found greenbacks in Hidden Valley Creek, RMNP (2,690 m), fed opportunistically on a wide variety of organisme. In Hidden Valley Creek, analyeis of greenback stomach contents revealed that terrestrial invertebrates comprised a relatively constant proportion of the diet through September, but the proportion of terrestrial invertebrates in the diet declined rapidly in October as temperatures declined. None of the stomachs contained YOY greenbacks. The stomach of an 1.19 kg pure (type A) Cascade Creek greenback, illegally taken from Lytle Pond, Fort Carson contained a 114 mm tiger salamander (Amvetoma tiarinum) in 1982. Variations in the Arkansas darter population that co-exists with the greenbacks in Lytle pond indicate that greenbacks eat these native darters, although this observation has not been confirmed by stomach analysis of the greenbacks. Size and Growth Behnke (1979) stated that, "Historically, it appears that the greenback seldom attained a large size. About 1-2 pounds seems to be typical maximum size given by old timers. In Twin Lakes, Colorado, during the late 1800's, the greenback did not exceed .a foot in length, while the yellowfin cutthroat (now extinct) attained a size of 10-12 pounds." Nonetheless, the size and growth of greenbacks varies, based upon the elevation and population size. In small headwater habitats, the greenback has attained a relatively large size of 356-380 mm as observed in the headwaters of the South Fork, Cache La poudre River, where it is much larger than most brook trout in similar habitat. In september. 1981, 40 pure (type A) Cascade Creek greenbacks were transferred to the fishless 0.4 ha Lytle Pond at an elevation of 1,889 m to establish a wild broodstock. Although none of these greenbacks exceeded 250 mm in september 1981, one male attained a total length of 510 mm and a weight of 2.00 kg by November 1983. Studies of tagged greenbacks in Lytle pond have shown a 79 mm and 410 9 increase for male greenbacks, and a 86 mm and 315 9 increase for pre-spawning females from April 1991 to April 1992. The growth rate of adult greenbacks at higher elevations can be much lower depending on a variety of factors including population density. This is demonstrated by two alpine lakes in RMNP (Sandbeach and Pear) where the exotic fish population had been removed. The lakes were stocked with 161 mm greenbacks at the rate of 22.7 to 26.0 kg/ha on June 30, 1989. After 10 weeks, the fish increased in length by an average of 57 mm (range 47-68 mm). 10