Relationships between River Relationships between River Environment & Aquatic Life Environment & Aquatic Life

Don SadaDon SadaWalker Basin Stakeholder MeetingWalker Basin Stakeholder Meeting

December 12, 2007December 12, 2007

Dr. Sudeep Chandra (UNR), Fish

Dr. Christian Fritzen (DRI), Periphyton

Dr. Kumud Archarya (DRI), Food Webs

Ron Hershey (DRI), Water Chemistry

Personal ExperiencePersonal Experience Aquatic Ecologist Aquatic Ecologist (30 years)(30 years)

– Understanding relationships between the environment and aquatic Understanding relationships between the environment and aquatic communities in West U.S.communities in West U.S.

High, middle, and low elevation streams, High, middle, and low elevation streams, rivers, and spring-fed environmentsrivers, and spring-fed environments– FishFish– Aquatic insectsAquatic insects– MollusksMollusks

River Goods & ServicesRiver Goods & Services Traditional Traditional

BenefitsBenefits ConsumptionConsumption

– IrrigationIrrigation– TransportationTransportation– Clean waterClean water

Other BenefitsOther Benefits– Flood controlFlood control– Waste purificationWaste purification– RecreationRecreation– Wildlife & fishWildlife & fish– Food supplyFood supply

Condition of U.S. RiversCondition of U.S. Rivers

PRESETTLEMENTPRESETTLEMENT

Free flowing riverFree flowing river 3,060,000 Miles3,060,000 Miles

Number of DamsNumber of Dams NoneNone

River Water QualityRiver Water Quality All UnimpairedAll Unimpaired

Extinction RatesExtinction Rates 1 sp./million years1 sp./million years

CURRENT CURRENT

Free Flowing RiverFree Flowing River 600 miles600 miles

Number of DamsNumber of Dams75,000 (> 2 m high)75,000 (> 2 m high)

River Water QualityRiver Water Quality> 33% Impaired> 33% Impaired

Extinction RatesExtinction Rates123 recorded since 1900123 recorded since 1900

Imperiled or EndangeredImperiled or Endangered - > 25% fish I or E- > 25% fish I or E

- > 50% mussels I or E - > 50% mussels I or E - > 33% crayfish I or E- > 33% crayfish I or E- > 25% amphibians I or E- > 25% amphibians I or E

RIVERENVIRONMENT

Nutrients

Energy BenthicCommunities

Water ColumnCommunities

Substrate Composition

Hydrograph

Turbidity

RiparianCommunities

GeologyGradient

River Environment & Aquatic Life River Environment & Aquatic Life

Environment ‘Drives’ Characteristics Environment ‘Drives’ Characteristics of Aquatic Lifeof Aquatic Life

– TemperatureTemperature

– SubstrateSubstrate

– NutrientsNutrients

– Current VelocityCurrent Velocity

– Hydrograph Hydrograph

ChallengesChallenges

Regional differences Regional differences – Fish Fish – MacroinvertebratesMacroinvertebrates

FlowFlow– Deserts vs. northeast U.S.Deserts vs. northeast U.S.

TopographyTopography– Mountainous Nevada vs. Mountainous Nevada vs.

‘flat’ east & midwest‘flat’ east & midwest

GENERALITIES FROM ELSEWHERE ARE INAPPROPRIATE FOR NEVADA

Regional Context ImportantRegional Context ImportantOne Example Doesn’t Work EverywhereOne Example Doesn’t Work Everywhere

Management Management potentialpotential

Restoration Restoration potentialpotential

Hydrograph Hydrograph considerationsconsiderations

Environmental Environmental assessmentassessment

State of KnowledgeState of Knowledge

Local ContextLocal Context– Few Sites & SporadicFew Sites & Sporadic

Fish, East Fork (CDFG) Fish, East Fork (CDFG)

– MacroinvertebratesMacroinvertebrates East ForkEast Fork Historic & scattered Historic & scattered

through Mason Valleythrough Mason Valley

Watershed ContextWatershed Context– Many Sites & FrequentMany Sites & Frequent

Water QualityWater Quality Flow manipulationFlow manipulation MacroinvertebratesMacroinvertebrates Fish distributionFish distribution Riparian studiesRiparian studies Environment and aquatic Environment and aquatic

life relationshipslife relationships

Truckee RiverWalker River

REGIONAL INFORMATION MEAGER COMPARED TO OTHERS

Walker River StudiesWalker River StudiesLocationsLocations

Eight SitesEight Sites

Base of Sierra Base of Sierra Nevada to LakeNevada to Lake– East and West ForksEast and West Forks– MainstemMainstem

Walker River StudiesWalker River StudiesMethodsMethods

Quantitatively Quantitatively Describe River Describe River Physical Habitat Physical Habitat

Quantify Spatial & Quantify Spatial & Seasonal Differences Seasonal Differences and Variation and Variation

– Water ChemistryWater Chemistry– Aquatic LifeAquatic Life

FishFish MacroinvertebratesMacroinvertebrates PeriphytonPeriphyton

ProductsProducts Determine existing biological and Determine existing biological and

environmental conditionsenvironmental conditions Understand northern Nevada’s rivers Understand northern Nevada’s rivers

within national contextwithin national context

Provide insight into restoration potential Provide insight into restoration potential and goalsand goals

Inform hydrologic models regarding the Inform hydrologic models regarding the consequences of different management consequences of different management decisionsdecisions