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water chemistry parameters at the 16.2 RKM translocation site were 216.2 mg/L for CO2, 12.7 for dissolved oxygen, 19.68 °C for temperature, 4,609 uS for conductivity, 7.3 for pH, and 5.0 NTUs for turbidity. Most parameters were similar to when humpback chub were released on August 1, 2003, except for slightly colder water temperatures and somewhat higher dissolved oxygen. Presumably, the highest CO2 levels should occur during baseflow when supersatured spring discharge does not become diluted by runoff. Fish Community We conducted a total of 1,345 hours of hoopnetting during the reconnaissance trip. We captured 2,293 speckled dace, 102 common carp (TL range = 35-105 mm), 33 fathead minnow, 3 black bullhead, (Amieurus natalis, TL range= 177-206 mm), 1 plains killifish (Fundulus zebrinus), 1 red shiner (Cyprinella lutrensis), and 1 green sunfish (Lepomis cyanellus, Figure 4). Speckled dace were by far the most common (94.2% of catch; 16.4±2.8 fish/hr) and were the only native fish captured. We captured the majority of common carp, fathead minnow, red shiner, and plains killifish in the nets closest to Chute Falls where dissolved CO2 was lowest. We visually observed two adult rainbow trout (Oncorhynchus mykiss) and six adult common carp. The 206 mm black bullhead's stomach contained an 85 mm fathead minnow; the other black bullhead's stomach was empty. During the translocation trip on August 1, 2003, we released 283 of 300 translocated humpback chub alive at 16.2 RKM; the other 17 individuals died during the acclimation process. The mean size of humpback chub (50 to 100 mm) released were smaller individuals (X=62 mm ± 0.66 SE; median=60 mm). Angling captured a 420 mm adult rainbow trout and we observed two other adults at the release site. The captured individual was over two years old (determined by otolith) and its stomach contained a humpback chub carcass that had previously died in the transportation tank and had been inadvertently discarded in the river (identified by elastomer dye). We conducted a total of 1,560 hours of hoopnetting during the monitoring trip (October 31- November 3, 2003). We captured 13,399 speckled dace (98.4% of catch), 42 humpback chub, 43 common carp (TL range = 60-198 mm), 121 fathead minnow, 7 channel catfish (Ictalurus punctatus, TL range = 62-93 mm), 3 plains killifish, and 1 black bullhead (TL=277 mm, Figure 5). No fish were captured in the gill and trammel net sets, nor were any large- bodied predator fish visually observed (probably due to low visibility). Humpback chub captured during the November trip ranged from 81 to 155 mm in length (X=114 mm ± 2.21 SE; median =115 mm). The yellow elastomer tags were only apparent on 33 of the 42 individuals. It was evident from the tagged individuals that most elastomer marks had faded over time. However, we cannot be certain whether the nine individuals with no visible tags had lost their marks or had migrated into this area from below Chute Falls. No elastomer tagged fish were identified downriver during the October 20-30, 2003 monitoring of the lower 13.6 RKM, but fading of the elastomer tags may have precluded any positive identification. The five nets closest to Chute Falls captured 78% of untagged 12