Escalante River 2016
Flannelmouth Sucker ( Catostomus latipinnis ) • Large-bodied • Protected under interstate Up to 30 inches conservation agreement • Long lived • Conservation actions Breed at 6 years of age − Non-native eradication • Widely distributed − Allowing passage at diversions Colorado River and tributaries Recent population declines • Threats − Non-native fishes − Water development − Habitat fragmentation
Bluehead Sucker ( Catostomus discobulus ) Medium sized Protected under - Grows to 14 inches interstate conservation Widespread agreement - Occupy higher elevations than Conservation actions Flannelmouth Sucker - Also found in Snake - Increasing passage at diversions River and Bear River - Non-native eradication basins • Threats - Water development - Hybridization with non-native suckers
Roundtail Chub ( Gila robusta ) Large Minnow Protected under interstate - Grows to 17 inches conservation agreement Widespread though rare Conservation actions - Inhabits Colorado River - Non-native eradication main-stem and most large tributaries - Habitat restoration including - Population declining flow regime alteration and non- - Lower Colorado River native vegetation removal population is a candidate for federal listing Threats - Habitat loss from water development and river morphology changes (i.e. loss of sediment and temperature changes) - Non-native fishes
Sampling Reaches
Sampling Methodology Sample 20 sites within each station Sites are contiguous areas of similar habitat (run, riffle, pool, backwater); Select individual sites in proportion to the availability of habitats Conduct three-pass depletion seining Attempt to seine ~ 5 x 10 m area (not always possible); Seine by moving downstream; Place fish from first two passes in separate buckets;
Sampling Methodology Categorize site according to: Habitat type; Dominant substrate type Habitat measurements… Measure width and length of area seined , using meter tape; Estimate depth of area seined by averaging depths experienced on each end of seine; Measure width and length of overall habitat sampled (note >25 m for such areas).
Results High abundance of Flannelmouth Sucker in Reach U2- U1 Abundance of Bluehead Sucker relatively low No Roundtail Chub observed 1.15 2.27 0.25 FMSU SE 0.46 SE 1.08 BHSU Number of fish per m ³ 0.20 RTCH 0.15 0.10 0.05 0.00 U2 U1 L1 L2 L3 Station
Results High numbers of Flannelmouth Sucker fry in reaches U2-U1 (n=494; 88% of total FM captured in all reaches; 298 of total FM were not measured) Large adult FM congregated in Reaches L2-L3 Number of Flannelmouth Sucker 50 186 N=262 45 40 35 30 25 20 15 10 5 0 0-10 31-40 61-70 91-100 121-130 151-160 181-190 211-220 241-250 271-280 301-310 331-340 361-370 391-400 421-430 451-460 481-490 511-530 Total length (mm)
Results Very few Bluehead Suckers captured (n=7) 408 unidentifiable Sucker fry 11-30 mm captured; 91% of those captured in Reaches U2-U1 215 unidentifiable fry captured; 96% of those captured in Reaches U2-U1 16 Number of Bluehead Sucker 14 12 10 8 6 4 2 0 11-20 31-40 51-60 71-80 91-100 111-120 131-140 151-160 171-180 191-200 211-220 231-240 251-260 271-280 291-300 311-320 331-340 351-360 371-380 391-400 Total length (mm)
Results 25 Number of Speckled Dace 42 Speckled Dace 20 captured 15 10 76 % captured in 5 Reaches U2-U1 0 0-10 101-110 111-120 121-130 11-20 21-30 31-40 41-50 51-60 61-70 71-80 81-90 91-100 Multiple ages classes; Total length (mm) reproduction confirmed
Non native fish captures 18 Brown Trout captured; 94% were captured in Reaches L1-L2 Calf Creek inflow at beginning of Reach L1 the likely source 7 Number of Brown Trout 6 5 4 3 2 1 0 0-10 31-40 61-70 91-100 121-130 151-160 181-190 211-220 241-250 271-280 301-310 331-340 361-370 391-400 421-430 451-460 481-490 511-530 Total length (mm)
Habitat 1.0 0.9 Proportion of sites 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 U2 U1 L1 L2 L3 Station Run Riffle Pool 1.0 0.9 Proportion of sites 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 U2 U1 L1 L2 L3 Station Sand Gravel Cobble Boulder Bedrock
2009-2016 0.25 2.27 1.16 2009 Flannelmouth Sucker per m 3 SE 1.07 SE 0.46 2011 0.20 2013 2015 0.15 2016 0.10 0.05 0.00 U2 U1 L1 L2 L3 Station 0.16 2009 0.14 Bluehead Sucker per m 3 2011 0.12 2013 0.10 0.08 2015 0.06 2016 0.04 0.02 0.00 U2 U1 L1 L2 L3 Station
2009-2016 2009 Number Flannelmouth n=181 60 n=323 2011 Sucker captured 2013 50 2015 40 2016 30 20 10 0 U2 U1 L1 L2 L3 Station 30 2009 Number Bluehead 2011 2013 captured Sucker 20 2015 2016 10 0 U2 U1 L1 L2 L3 Station
Hoop Netting Goal; to collect Roundtail Chub fin clips for genetic analysis prior to supplemental stocking. provide an additional sampling effort for Three Species monitoring of the Escalante River
Methods 15 nets Set over a two day period Set overnight Set in locations where RTCH were caught in previous sampling efforts (2015) Targeted RTCH habitat (deep pools with low velocity, deep runs w/cover) Water depth, temperature, set time, UTM at each site.
Methods Pull nets the next day Fish collected in live wells All fish measured Non-natives removed Natives released
Results No Roundtail Chub captured 0.350 0.300 0.250 Flannelmouth Sucker 0.200 Bluehead Sucker CPUE Specled Dace 0.150 Brown Trout Flathead Catfish 0.100 0.050 0.000 SPECIES Bluehead Flannelmouth Sucker Speckled Dace Brown Trout Flathead Catfish Sucker Total captures 80 19 34 6 3 Adult 0.293 0.070 0.125 0.022 0.011 Young 0.000 0.000 0.000 0.000 0.000 Total 0.293 0.070 0.125 0.022 0.011
Number of Flannelmouth Sucker 10 0 1 2 3 4 5 6 7 8 9 0-10 31-40 61-70 91-100 121-130 Results 151-160 Total length (mm) 181-190 211-220 241-250 N=80 271-280 301-310 331-340 361-370 391-400 421-430 451-460
Number of Bluehead Sucker 10 0 1 2 3 4 5 6 7 8 9 0-10 21-30 41-50 61-70 81-90 Results 101-110 Total length (mm) 121-130 141-150 161-170 181-190 201-210 N=19 221-230 241-250 261-270 281-290
Spot seining Seined pools and runs not ideal for hoop nets between sets All fish captured were identified and measured Non-natives were removed Natives released
Results Table 1. Total fish captured and catch per effort during spot seining of the Escalante River, June 26-27, 2016. Flannelmouth Sucker Bluehead Sucker Specled Dace Browm Trout Number of Seine Date Hauls Total CPE 1 Total CPE 1 Total CPE 1 Total CPE 1 6/27/2016 60 23 0.383 8 0.133 5 0.083 3 0.050 6/28/2016 43 38 0.884 11 0.256 2 0.047 1 0.023 Total 103 61 0.592 19 0.184 7 0.068 4 0.039 1 CPE = catch per effort
Number of Bluehead Sucker Number of Flannelmouth Sucker 10 10 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0-10 0-10 21-30 31-40 41-50 61-70 61-70 91-100 81-90 121-130 Results 101-110 Total length (mm) 151-160 Total length (mm) 181-190 121-130 211-220 141-150 161-170 241-250 271-280 181-190 N=61 301-310 201-210 N=19 331-340 221-230 361-370 241-250 391-400 261-270 420-430 281-290 451-460 301-310
Conclusion Native sucker reproduction confirmed Recruitment from 2015 year class was unconfirmed Large, older adult native sucker population is robust No Roundtail Chub present in sampling reaches
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