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. respectively) (Table 3). Catch rates over the entire period of pikeminnow abundance estimates were 0.08 fish/hour and 0.03 fish/hour for smallmouth bass removal. No statistical analyses were performed on the data from the northern pike removal project because pike were not removed by pass. We can, however, qualitatively compare our catch rates with those from the Yampa River, a likely source of middle Green River pike. Reviewing annual reports and preliminary data from the northern pike removal projects there, catch rates are slightly higher, but have also been declining since the beginning of the projects. In the upper Yampa River, between Hayden and Craig, CO (RKM 275 - RKM 215.7 (RM 170.9 - RM 134)), electrofishing catch rates have gone from 8.0 pike/hour in 2004 down to 4.3 pike/hour in 2006 (Table 5). Electrofishing catch rates in the middle Yampa River (RKM 223.7 - RKM 95.0 (RM 139 - RM 59)) are also higher than in the middle Green River and have declined over the study period: 2.15 pike/hour in 2004 down to 1.43 pike/hour in 2006. Middle Yampa River removal crews did not set fyke nets until 2006. Catch rates for this gear type were low (0.12 fish/fyke-net night), which is similar to those seen in the middle Green River. . . . . . . Age Analysis In 2001, cleithra from 217 northern pike indicate age classes from young-of-year (YOY) through age 10 were present. Most pike collected were two to four years old and ranged from 400 to 800 mm in length. Only 12 pike were aged older than six years (Figure 7). All but one fish (a 295 mm YOY) captured in 2002 were identified as two to seven years old (Figure 7). The majority of these were actually in the four to five year-old range. In 2003, again, most fish were identified as four or five years old. Only three fish were identified as one- or two-year-old fish. The remaining fish were age-six or older. In 2004, the majority of fish were one-year-old fish, . . . 20 .