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The Use of Biological Indicators for the Evaluation of Multiple Stressors

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The Use of Biological Indicators for the Evaluation of Multiple Stressors TheThe UseUse ofof BiologicalBiological IndicatorsIndicators forfor thethe EvaluationEvaluation ofof MultipleMultiple StressorsStressors andand thethe IdentificationIdentification ofof ImpairmentsImpairments inin StreamsStreams Timothy J. Ehlinger University of Wisconsin-Milwaukee March 19, 2008 Student Collaborators: • Richard Shaker (UW-Milwaukee) • Angela Ortenblad (UW-Milwaukee) • Jennifer Grzesik (UW-Milwaukee) DataData CollectedCollected && AnalyzedAnalyzed Fish Abundance and Species Composition Aquatic Macroinvertebrate Communities Stream Hydrology Water Quality and Nutrients Habitat Quality USUS FederalFederal CleanClean WatersWaters ActAct (CWA)(CWA) “Congressional declaration of goals and policy” to achieve the “Restoration and maintenance of chemical, physical and biological integrity of Nation’s waters…” TheThe 33 DimensionsDimensions ofof EcologicalEcological IntegrityIntegrity ((CWACWA)) Physical Chemical Integrity Integrity Biological Integrity Ecological Integrity WaterWater QualityQuality StandardStandard ConsistsConsists ofof threethree basicbasic elements:elements: DesignatedDesignated usesuses ofof thethe waterwater bodybody e.g., recreation, water supply, aquatic life, agriculture “Fishable and Swimable” WaterWater qualityquality criteriacriteria toto protectprotect designateddesignated usesuses numeric pollutant concentrations and narrative requirements AnAn antidegradationantidegradation policypolicy toto maintainmaintain andand protectprotect existingexisting usesuses ImpairedImpaired WatersWaters inin thethe LowerLower FoxFox RiverRiver BasinBasin Data from: Wisconsin DNR March 2006 IncreasedIncreased UseUse ofof ofof BiologicalBiological IntegrityIntegrity inin establishingestablishing UseUse ClassificationsClassifications andand CriteriaCriteria forfor meetingmeeting WaterWater QualityQuality StandardsStandards ““The Ability of an Aquatic Community to support and maintain a structural and functional performance comparable to the natural habits of a region.” As modified from Karr and Dudley (1981) CauseCause andand Effect:Effect: Linking stressors to the resultant biological response Habitat Structure Flow Regime Stressor Water Quality Biological Agent(s) & Toxicity Response Energy Sources Biotic Interactions Stressors Stress / Exposure Response (Yoder and Rankin, 1998)(Karr and Yoder, 2004) The Five Major Factors Which Determine the Integrity of Aquatic Resources Alkalinity Solubilities Temperature Velocity High/Low D.O. Land Use Adsorption Extremes pH Chemical Flow Nutrients Variables Turbidity Ground Regime Water Precipitation & Organics Hardness Runoff INTEGRITY OF THE Disease Parasitism WATER RESOURCE Reproduction Biotic Factors Feeding Competition Predation “Principal Goal of the Clean Water Act Nutrients Riparian Sunlight Energy Vegetation Width/Depth Source Seasonal Cycles Bank Stability Organic Matter Siltation Habitat Channel Morphology Inputs 1oo and 2 Structure Sinuosity Production Gradient Current Instream Substrate Cover Canopy MultipleMultiple StressorsStressors andand NonlinearNonlinear FunctionalFunctional ResponseResponse RelationshipsRelationships ConceptConcept ofof anan IndexIndex ofof BioticBiotic IntegrityIntegrity From Molles (2006), McGraw-Hill Inc. SomeSome FishesFishes ofof thethe FoxFox RiverRiver andand ItIt’’ss TributariesTributaries Multimetric Components of Biological Integrity Biological Condition LOW N H a T i t g i o h v S le ly e p r e a S I c n p n ie t e [Effect of Human Activity t s o c i l e Stressor Gradient e s r a nt S pe c i e s ] Deformities and Anomalies HIGH Metrics used for Wisconsin Fish IBI for Warmwater, Wadeable Streams Species richness and composition 1. Total number of native species 2. Number of darter species 3. Number of sucker species 4. Number of sunfish species 5. Number of intolerant species 6. Percent (by number of individuals) that are tolerant species Trophic and reproductive function 1. Percent that are omnivores 2. Percent that are insectivores 3. Percent that are top carnivores 4. Percent that are simple lithophilous spawners Fish abundance and condition (correction factors) 1. Number of individuals (excluding tolerant species) per 300 m sample 2. Percent with deformities, eroded fins, lesions, or tumors (delt) Scoring Criteria for Wisconsin Version of the Fish IBI Metric or correction factor Scoring Criteria 10 7 5 2 0 Total number of native* species >25 20-25 15-20 10-15 <10 Number of darter species* >5 4-5 3.0-3.9 2.0-2.9 <2 Number of sucker species* >6.0 4.7-6.0 3.0-4.6 2.3-2.9 <2.3 Number of sunfish species* >4.0 3.3-4.0 2.0-3.2 1.7-1.9 <1.7 Number of intolerant species* >6.5 5.3-6.4 4.0-5.2 2.7-3.9 <2.7 Percent (by total individuals) that are 0-19 20 21-49 50 51-100 tolerant Percent that are omnivores 0-19 20 21-39 40 41-100 Percent that are insectivores 100-61 60 59-31 30 29-0 Percent that are top carnivores 100-15 14 18-8 7 6-0 Percent that are simple lithophilous 100-51 50 49-21 20 19-0 spawners Number of individuals (excluding tolerant If < 50 fish, subtract 10 from overall IBI score species) per 300 m sampled Percent with deformities, eroded fins, If ³ 4%, subtract 10 from overall IBI score lesions, or tumors (DELT) *values vary by region of state, values in table represent Central/Southern Wisconsin, Source: Lyons, 1992 40 Contributions to Fish IBI 35 Contributions to Fish IBI 30 Poor 25 20 15 10 5 Very Fair Poor0 -5 2003 2004 Apple Creek Ashwaubenon Baird Creek Duck Creek Spring Brook 2005 2006 2003 2004 2006 2003 2004 Stream/Year 2005 Fish abundance 2006 Simple lithotrophs Carnivores 2003 Insectivore 2004 Omnivores Tolerant 2006 Intolerant sp. Sunfishes 2003 Sucker sp. 2004 Darter sp. Native species 2006 CauseCause andand Effect:Effect: Linking stressors to the resultant biological response Habitat Structure Flow Regime Stressor Water Quality Biological Agent(s) & Toxicity Response Energy Sources Biotic Interactions Stressors Stress / Exposure Response (Yoder and Rankin, 1998)(Karr and Yoder, 2004) ExploringExploring HumanHuman--EnvironmentalEnvironmental ImpactsImpacts usingusing GeoGeo--SpatialSpatial AnalysisAnalysis ImpactsImpacts ofof ChangingChanging Landscapes:Landscapes: Baird Creek Satellite Images: 1960 2005 LandscapeLandscape vsvs LandLand CoverCover PredictorsPredictors ofof IBIIBI r2 = 0.84 FoxFox RiverRiver TributaryTributary HabitatHabitat RatingsRatings PotentialPotential StressorsStressors AffectingAffecting BiologicalBiological IntegrityIntegrity ofof FishFish andand InvertebratesInvertebrates Bank Erosion Substrate Composition Riparian Vegetation Canopy Cover Depth and Flow Water Quality ImpairmentsImpairments IdentifiedIdentified fromfrom BiologicalBiological MonitoringMonitoring AbundanceAbundance ofof FishFish andand InvertebratesInvertebrates Flow Regime Flashy peak flows Low base flows SpeciesSpecies CompositionComposition Habitat Siltation and bank erosion AbundanceAbundance ofof TolerantTolerant SpeciesSpecies Dissolved Oxygen EutrophicEutrophicationation and Nutrient loading We end, I think, at what might be called the standard paradox of the twentieth century: our tools are better than we are, and grow faster than we do. They suffice to crack the atom, to command the tides. But they do not suffice for the oldest task in human history: to live on a piece of land without spoiling it. Aldo Leopold, 1938 SelwaySelway--BitterrootBitterroot WildernessWilderness .
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