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Alison Harwood Ecologist. Assessment of Fish Abundance and Species Composition at Selected Sites in South Dakota: An Overview. Overview. 64 sites visited in 2008-09 62 wadeable sites 2 boatable sites 4 sites repeated within 2008-2009 assessment for QA/QC
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Alison Harwood Ecologist Assessment of Fish Abundance and Species Composition at Selected Sites in South Dakota: An Overview
Overview • 64 sites visited in 2008-09 • 62 wadeable sites • 2 boatable sites • 4 sites repeated within 2008-2009 assessment for QA/QC • 4 sites revisited from 2000-2004 assessment • Fish collected at 60 sites
Sampling Procedures: Wadeable Streams • Equipment • Smith-Root backpack electroshocker • 9” ring anode, rat-tail cathode • fishing net • bucket for fish • Safety equipment • insulated waders • lineman gloves • personal flotation devices
Sampling Procedures:Wadeable Stream • 1 netter and 1 fisher move upstream • Reaches < 500 m • fished continuously in all habitat • Reaches > 500 m • fished along banks, alternating sides for each subreach • Fish identified at end of reach (< 500 m) or each subreach (> 500 m)
Sampling Procedures: Boatable Streams • Equipment • boat electroshocker • fishing net • livewell • Safety Equipment • lineman gloves • personal flotation devices
Sampling Procedures:Boatable Streams • 1 operator and 1 netter move downstream • Fished for the lesser of an • entire length of a subreach or • 700 seconds • Alternated banks as shown below • Fished for the lesser of the entire reach or 500 individuals • Fish identified at the end of each subreach
Results • Fish collected at 60 of 64 sites • Sampling conditions were not suitable at remaining 4 sites: • insufficient habitat • unsuitable conductivity in water
Results • 3,508 individuals collected from wadeable streams • Diversity in streams ranged from 0-11 species • 41 total species caught • Goldeye • Flathead minnow • Brook trout • Several others…
Results • 893 individuals collected from boatable streams • Diversity in streams ranged from 6-26 species • 29 total species caught • Shortnose Gar • Paddlefish • Shovelnose Sturgeon • Several others…
Results • Frequently sampled fish: • Sand Shiner (Notropis stramineus)- 609 individuals • Green Sunfish (Lepomus cyanellus)- 563 individuals • Fathead Minnow (Pimephales promelas)- 389 individuals • Heritage species identified: • Skipjack Herring (Alosa chrysochloris) – 6 individuals
Species Diversity By Site South Dakota Counties
Species Diversity By Site • 2 basins had an average of < 5 species/site • Grand River Basin • White River Basin • Conditions in these streams did not allow for a high diversity of fish South Dakota Counties
Species Diversity By Site • Some commonalities among streams with < 5 species detected: • sandy/muddy bottom • little overhanging vegetation on banks • few riffle areas • high amounts of suspended sediment • little structure in river (i.e., few logs, large rocks, etc.)
Anomalies • Common anomalies included: • parasitic lesions • “black spot disease” • tumors Possible tumor Black Spot disease
Revisited Sites • 2000-04 • Both seine netting and electrofishing methods used • 2008-09 • Only electrofishing used • Did this affect fishing efficiency?
Revisited Sites • Sampled more individuals and more species in 2 of the sites • Sampled fewer individuals and fewer species in 2 of the sites • Differences may be attributable to many factors, not just sampling method
Conclusion • The EPA will be evaluating the samples collected during the study. • Changing the fish sampling methods did not appear to affect the numbers of fish sampled.
Acknowledgements • Thank you to all of the technicians and staff members who helped with the field collection. • John Clark • Rachael Yarger • Kathy Neitzert • Darin Larson • Ashli Maddox • Parker Norton • Galen Hoogestraat • Kammy Durham • Ryan Thompson • Tyler Meyer • 2 personnel from the Nebraska Water Science Center • Numerous landowners and Tribes for granting us access onto their lands