Macroinvertebrate Macroinvertebrate Bioassessment ToolsBioassessment Tools

Aquatic Life/Nutrient WorkgroupAquatic Life/Nutrient Workgroup

August 11, 2008August 11, 2008

Discussion TopicsDiscussion Topics

Reference and stressed site statusReference and stressed site status O/E (RIVPACS) preliminary resultsO/E (RIVPACS) preliminary results MMI (multimetric index) preliminary resultsMMI (multimetric index) preliminary results BioclassesBioclasses

Reference Site ReviewReference Site Review

Two part process:Two part process: Calculated GIS-based human disturbance values and Calculated GIS-based human disturbance values and

established criteria cutoffsestablished criteria cutoffs Reviewed and critiqued aerial images at EPA using Reviewed and critiqued aerial images at EPA using

Global ExplorerGlobal Explorer

11 additional ref sites added to fill obvious 11 additional ref sites added to fill obvious spatial gaps and large rivers in plains and spatial gaps and large rivers in plains and xeric bioregionsxeric bioregions

Reference SitesReference Sites

168 reference sites finalized in April (90 mnts, 39 168 reference sites finalized in April (90 mnts, 39 plains, 39 xeric)plains, 39 xeric)

4 xeric, 4 plains and 1 mnts sites removed later4 xeric, 4 plains and 1 mnts sites removed later All USFS sites (n=16) retained – midges ID’ed All USFS sites (n=16) retained – midges ID’ed

down to genusdown to genus 12 additional sites w/ low taxa counts could be 12 additional sites w/ low taxa counts could be

removed (USU and TT testing)removed (USU and TT testing)

Reference SitesReference Sites

Stressed Site ReviewStressed Site Review

Flagged human disturbance values (GIS Flagged human disturbance values (GIS derived) that exceeded “acceptable” derived) that exceeded “acceptable” conditions and further reviewed with conditions and further reviewed with Google Earth imagesGoogle Earth images

Sites exhibiting clear characteristics of Sites exhibiting clear characteristics of stressed condition retained after image stressed condition retained after image reviewreview

Stressed SitesStressed Sites

Goal: identify unquestionably stressed Goal: identify unquestionably stressed sites – no marginal onessites – no marginal ones

74 stressed sites finalized in June74 stressed sites finalized in June 31 mnts, 23 plains & 20 xeric31 mnts, 23 plains & 20 xeric

Stressed SitesStressed Sites

O/E Model ProgressO/E Model Progress

Predictor variables calculatedPredictor variables calculated OTU’s assignments redefinedOTU’s assignments redefined

Improved resolutionImproved resolution

Replicate #’s organized & sample IDs Replicate #’s organized & sample IDs selectedselected

Reference sites reviewed by Utah St staff Reference sites reviewed by Utah St staff 6 sites suggested for removal based on additional 6 sites suggested for removal based on additional

aerial image review – WQCD agreedaerial image review – WQCD agreed

O/E Preliminary ModelingO/E Preliminary Modeling

USU modeling based on 143 ref sites and 282 USU modeling based on 143 ref sites and 282 taxa (OTU's)taxa (OTU's)

Rare taxa not used (106 taxa remained)Rare taxa not used (106 taxa remained) Cluster analysis/ordinationCluster analysis/ordination

Used presence/absence of taxa among sitesUsed presence/absence of taxa among sites

Investigating 2 alternate groupings:Investigating 2 alternate groupings: 3 classes – Ecoregions3 classes – Ecoregions 13 classes – Bioclasses 13 classes – Bioclasses

O/E Preliminary ModelingO/E Preliminary Modeling

Spatial distribution of samples coded by 3 bug-defined Spatial distribution of samples coded by 3 bug-defined classesclasses

Performance PlotPerformance Plot

Sites coded by Sites coded by bioregionbioregion

Good agreement Good agreement between what the between what the model predicts at a model predicts at a site and what is site and what is observedobserved

O/E Preliminary ModelingO/E Preliminary Modeling

Spatial dist. of samples coded by 13 bug-defined classesSpatial dist. of samples coded by 13 bug-defined classes

Performance PlotPerformance Plot

Sites are coded by Sites are coded by the group the group assignmentsassignments

Different types of Different types of streams vary in streams vary in predicted and predicted and observed richnessobserved richness

rr22 = 0.85 = 0.85

MMI Preliminary ModelingMMI Preliminary Modeling

Tetra Tech keeping in sync with Utah Tetra Tech keeping in sync with Utah State workState work Same OTU designations, predictor variables, Same OTU designations, predictor variables,

reference sites and samples usedreference sites and samples used

Retained rare taxa – Tetra Tech Retained rare taxa – Tetra Tech investigatinginvestigating further further

Preliminary FindingsPreliminary Findings

Tetra Tech’s ordination similar to Utah Tetra Tech’s ordination similar to Utah State’sState’s Geographic ecoregions not a perfect fitGeographic ecoregions not a perfect fit

Biology is sensitive to the natural gradients Biology is sensitive to the natural gradients in temp. and water amount across the in temp. and water amount across the landscapelandscape

Bioclasses may work better than Bioclasses may work better than ecoregionsecoregions

BioclassesBioclasses

Not defined by geographic regionsNot defined by geographic regions Defined more by broad habitat Defined more by broad habitat

characteristicscharacteristics Doesn’t lend itself to drawing lines on a Doesn’t lend itself to drawing lines on a

mapmap

Bioclass ExampleBioclass Example

Primary predictors appear to be summer Primary predictors appear to be summer water temperature and amount of waterwater temperature and amount of water

Amt of water = Amt of water = ƒƒ (watershed area, (watershed area, precipitation)precipitation)

Stream temp = Stream temp = ƒƒ (amount of water, (amount of water, elevation, latitude)elevation, latitude)

BioclassesBioclasses

Two sites, close together geographically, Two sites, close together geographically, can be in two very different bioclassescan be in two very different bioclasses Mainstem (large watershed) vs. tributary (small)Mainstem (large watershed) vs. tributary (small)

We do some of that already with We do some of that already with mainstems separated from “all tribs,” but mainstems separated from “all tribs,” but not consistentlynot consistently

ExampleExample

How we might identify bioclass membershipHow we might identify bioclass membership

Bioclass xyzBioclass xyz

>100 km>100 km22 Watershed AreaWatershed Area <250 km<250 km22

> 1250 m> 1250 m ElevationElevation <2000 m<2000 m

>ddd.dd>ddd.dd LongitudeLongitude <eee.ee<eee.ee

Upcoming WorkUpcoming Work

Tetra Tech will try further classifications by Tetra Tech will try further classifications by removing rare taxaremoving rare taxa

Critically reviewing how to standardize analysis Critically reviewing how to standardize analysis & treatment of data& treatment of data

Move deeper into the modeling processesMove deeper into the modeling processes O/E – predictive modelingO/E – predictive modeling O/E – estimating probability of capture (pc) & EO/E – estimating probability of capture (pc) & E MMI – metric calculationsMMI – metric calculations

Questions?Questions?

Drunella doddsi

Baetis tricaudatusMayfly

Mayfly

InformationInformation

Utah State website on Predictive Models:Utah State website on Predictive Models: http://129.123.10.240/WMCPortal/http://129.123.10.240/WMCPortal/

DesktopDefault.aspx?tabindex=2&tabid=27DesktopDefault.aspx?tabindex=2&tabid=27

Bioassessment tool info and PowerPoint Bioassessment tool info and PowerPoint presentations:presentations: http://www.cwqf.org/Workgroups/Aquatic.asphttp://www.cwqf.org/Workgroups/Aquatic.asp