8025 - Laserfiche WebLink

Home Browse Search

20 Colorado squawfish were also captured in stratum S. Two adults were captured on 20 May 80 and 7 May 81 at RM 33.0 and 30.8, respectively. DOW personnel captured an adult squawfish on 25 August 81 at RM 33.8. GJFS observed an adult during electrofishing on 20 May 80 at RM 31.4. Small fish were quite numerous in this strata~ as indicated by a total area CPE of 14.48 fiSh/10m2 (Table 4). Stratum S yielded the highest density of larger fish based on total hour CPE of 332.36 fishl10 hr (Table 5). This was considerably higher than the other strata in the Gunnison River. Dolores River Stratum T. Statum T yielded the most diverse fish fauna of all strata sampled in the Dolores River, with 14 species. Non-natives . comprised 95% of the total catch, and accounted for 10 of the 14 species captured. Sand shiner (40.9%), red shiner (38.6%) and fathead minnow (11.4%) were the most frequently collected species in stratum T. Roundtail chub was the most common native species caught. CPE for area and hour gears for each species in each stratum sampled in the Dolores River are shown in Tables 6 and 7. The total CPE using area gear was 10.8 fish/10m2 which was similar to strata U and V. Total CPE using hour gear was 22.29 fishl10 hr, which was low compared to the other strata in the Dolores River. Stratum U. Thirteen species were captured in stratum U. Nine non-native species represented approximately 92% of all fishes caught. Sand shiner (50.0%), red shiner (28.0%) and fathead minnow (9.8%) were the three most abundant species observed. Roundtail chub, flannelmouth suck~r, bluehead sucker and speckled dace were collected but were not common. The total CPE using area gear was 16.73 fiSh/10m2 which was slightly higher than strata T and V (Table 6). Total CPE using hour gear in stratum U was the lowest (18.44 fishllO hr) of all strata in the Dolores River (Table 7). Stratum V. Eight of the 12 species captured from stratum V were non- natives. These also made up three-fourths of the total catch, and included sand shiner (29.8%), fathead minnow (24.1%), and red shiner (16.3%). Total CPE using area gear was 11.07 fish/10m2 (Table 6). The total CPE for hour-based gear was greater in stratum V (60.6 fish/10 hr) than the two downstream strata (Table 7). Stratum W. Only nine fish were collected from stratum W in May 1981. Roundtail chub, flannelmouth sucker, common carp and bluehead sucker were the four species observed. No fish were collected from this stratum after May 1981 because water levels were too low to sample. It was highly unlikely that fish inhabited this stratum during extreme low flows.