Priority Living Resource Areas

1. Priority Living Resource Areas Using GIS and Expert Judgment to Identify Target Species “Hot Spots” John Wolf and Mike Fritz Chesapeake Bay Program Office May 22, 2007

2. Habitat Requirements for Chesapeake Bay Living Resources

3. Species Selection • From HR2 • Fish • Shellfish • Added species for which “new” potential habitat information existed • SAV handled separately

4. Menhaden Striped Bass Anchovy Alewife Hickory Shad American Shad Yellow Perch White Perch Blueback Herring Largemouth Bass* Chain Pickerel* Blue Crab Oyster Soft Shell Clam Hard Shell Clam Spot Speckled Sea Trout Postlarvel Blue Crab* Catfish* Summer Flounder* Atlantic Sturgeon* Croaker* Species Considered Water Column Bottom * species or layers not included in HR2

5. Assumptions • For species with potential habitat distribution maps for multiple life stages, composite maps were produced by combing individual GIS layers

6. Assumptions (cont.) • Water Column and Bottom Species initially kept separate • Each species treated equally (no weighting) • SAV treated separately

7. Non-HR2 Species Decision Rules Based on interpolated spring and summer salinity 1985-1997

8. Non-HR2 Species Decision Rules • Based on affinity for eelgrass beds – SAV Tier II within historic extent of eelgrass (VIMS) • Postlarval blue crab • Juvenile speckled sea trout • Potential Oyster Habitat • Yates for MD (CBL) • Baylor for VA (VMRC) • Private Oyster Leases for VA (VMRC) • Oyster Sanctuaries (MD)

9. GIS Process • Digital boundaries of habitats • Combine multiple life stage maps into single species map • For (a) water column and (b) bottom species, overlay each of the 11 species maps • Identify number of target species occupying the same habitat areas

10. Co-occurrence of Bottom Species

11. Co-occurrence of Water Column Species

12. GIS Process • Digital boundaries of habitats • Combine multiple life stage maps into single species map • For (a) water column and (b) bottom species, overlay each of the 11 species maps • Identify number of target species occupying the same habitat areas • Team members look for clusters that reflected natural “break points” • Establish “high priority” and “medium priority” ranges based on number of species • Combine water column and bottom species to produce draft PLRA’s

13. Draft Priority Living Resource Areas

14. SAV Process • Developed by SAV Workgroup • Examined … • - changes in SAV cover from 1992-1997 using VIMS aerial survey data, and • - SAV status as percentage of Tier II are in 1997 by CBP segments • Priority SAV* areas were … • - segments that lost over 60 hectares of SAV from 1992 to 1997 • - segments that had no mapped SAV in 1997 * These layers were NOT combined with the fish and shellfish layers because they were based on different data and used at different spatial scales. They were compared visually with PLRA’s. All SAV areas overlapped except for four small tributaries

15. Priority SAV Areas were those that lost over 60 HA of SAV from 1992 to 1997

16. Segments with No SAV Mapped in 1997

17. Final Priority Living Resource Areas

18. Monitoring Segments with PLRA’s