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could not be closely adhered to because the number of broodfish and rearing facilities were limited. As more captive razorback sucker matured more fish would be available for spawning and therefore more progeny would be produced. As additional facilities and grow-out ponds became available, the increased space would provide more flexibility and allow family lots and year classes to be divided up and reared in different locations and under different conditions to allow differential growth. It was speculated that in 1996 and 1997, the number of fish available for stocking would fall well short of the number projected for stocking. However, it was believed. that by 1998, additional rearing facilities and space would become available and more broodfish would be available to produce more young fish. Therefore, the projected number of fish to be stocked in both the Upper Colorado and Gunnison rivers in 1998 and subsequent years was increased. As more information was obtained on the return rate of stocked fish, study direction changed in 2001. Because of this, the size of razorback sucker to be produced and stocked was adapted. Preliminary results from the recapture of stocked razorback sucker from this and similar ongoing monitoring programs in the San Juan River indicated that return of razorback sucker stocked at lengths less than 200 nun was low. Stocking razorback sucker smaller than 200 mm may be futile because it was assumed that their post-stocking performance (i.e., survival) in the wild was poor. In light of these data, in 2001, managers made the decision to stock only those razorback sucker harvested from grow-out ponds that were 200 nun or larger into the Upper Colorado and Gunnison rivers. Razorback sucker that were less than 200 mm were returned to grow-out ponds to grow larger. Thus, the plan to stock the number and sizes of razorback sucker originally recommended for 2000 and 2001 into the Upper Colorado and Gunnison rivers (see Table 1) was abandoned. Another reason for the discontinuance was that there was a facility limitation. In other words, there simply was not enough grow-out pond acreage at the time to produce the numbers and sizes of razorback sucker recommended to be stocked annually in both the Upper Colorado and Gunnison rivers. General Domestic-produced and reared razorback sucker were stocked in the Gunnison River starting in the fall of 1995 and continued through the fall of 2001. Eighty-one family lots of razorback sucker were stocked during this period. A total of 18,395 juvenile, sub-adult, and adult razorback sucker were stocked in the Gunnison River during this period. Twenty-five fish captured from Etter Pond were re-located and stocked in the Gunnison River in April 1994 (2 1) 15