OYSTER HABITAT RESTORATION- HOW MUCH IS ENOUGH? USING ECOSYSTEM SERVICES TO SET RESTORATION OBJECTIVES ON A SYSTEM WIDE SCALE

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1 OYSTER HABITAT RESTORATION- HOW MUCH IS ENOUGH? USING ECOSYSTEM SERVICES TO SET RESTORATION OBJECTIVES ON A SYSTEM WIDE SCALE Boze Hancock Line zu Ermgassen Rob Brumbaugh Mark Spalding Bryan DeAngelis Jenn Greene Elizabeth Schuster

2 Acknowledgements Donors NOAA Restoration Center National Fish and Wildlife Foundation Lyda Hill Foundation, Kabcenell Family Foundation, Quay Charitable Foundation, Shell, and the Turner Foundation Partners Patrick Banks Loren Coen Brett Dumbauld Steve Geiger Jonathan H. Grabowski Raymond Grizzle Lisa Kellogg Mark Luckenbach Kay McGraw Summer Morlock Michael F. Piehler Sean Powers Bill Rodney Jennifer Ruesink Philine zu Ermgassen Rob Brumbaugh Mike Beck Boze Hancock Mark Spalding

3 OUTLINE Describing a mature project -now 5 years US based work, broadly applicable Provide a framework for setting objectives- System scale Quantifying ecosystem services Focus on fish production Packaging the information - influence management

4 Oyster Reefs at Risk In review: not for distribution Overall, 85% loss of oyster reef ecosystems in bays and ecoregions Beck et al Bioscience

5 Oyster Habitat Restoration HOW MUCH IS ENOUGH?? Beyond Aspirational Goals Change in oyster biomass Chesapeake x increase over 1994 by 2010 Puget Sound Washington 100 acres by 2020 Hudson Raritan NY/NJ 500 acres by acres by 2050 Tampa Bay Florida Preservation of 44 acres Great Bay New Hampshire 20 acres by 2010 Chesapeake Bay Exec. Order; Restore 20 tributaries by 2025 Zu Ermgassen et al 2012 Harris Ck- 377 acres!

6 Enough of what? Ecosystem Services Societal Benefits Regulating Provisioning What do we Supportive GAIN? Cultural The Nature Conservancy

7 Oyster Habitat restoration - # increasing

8 Targets are set on bay or estuary-wide levels How we ve been doing it VS How we could be doing it

9 Setting Water Filtration Goals Filtration Very high filtration rates Filtration Rates > Flushing Rates You need # ha of oyster reef to get there Eastern Oyster FR = 8.02W 0.58 e (-0.015T-27)2 Where W is dry tissue mass, T is temperature C Olympia Oyster zuermgassen et al FR = 3.60W 0.26 e (T-25)2 Where W is dry tissue mass, T is temperature C zuermgassen et al. 2013

10 Setting Denitrification Goals Denitrification Highest DNF rates recorded Nutrient reduction targets You need # ha of oyster reef to get there

11 Estimating Fisheries Production Quantitative studies (31) Gulf and Atlantic Identify consistently enhanced species Determine density by size class of fishes on oyster reef and control bottom Apply published growth rate and age specific survival of identified species Calculate species specific enhancement Calculate uncertainty in production Total production and uncertainty

12 Estimating Production - Adults No attempt to estimate growth enhancement of larger size classes. Did collect data on the relative abundance of adults (species not already recruitment enhanced) - potential indicator of benefit to growth.

13 mm Estimating Fisheries Production Gulf of Mexico Gulf of Mexico

14 Estimating Fisheries Production

15 Tools On-line Tools Managers Guide Training Workshops Policy Brief

16 On-Line Tools

17 On-Line Tools

18 How does this project fit with the rest of our work? It is NOT a replacement for evaluation! Objectivesetting models Assess site suitability Monitor performance Implement projects Working at MULTIPLE LEVELS to achieve sustainable restoration

19 Questions

20 Estimating Fish Production Challenges: Determining fish dependence on reef - Lack of data (dietary, home range etc.) - Changes in habitat use over time Few appropriate methods for determining density of younger age classes Intrinsic uncertainty in life history parameters (ubiquitous in fisheries studies)

21 WATER QUALITY REGULATION BY SHELLFISH IS FUNCTION OF ABUNDANCE Clearance Time (days) 10,000 1, No Water Quality Benefits Chesapeake Bay - today Chesapeake Bay ~ 1870s WQ Benefits Residence Times SF Bay: 11 Ches Bay: Narragansett: 27 Delaware Bay: ,000 10,000 Residence Time (days) Adapted from: R. Dame, Ecology of Marine Bivalves: An Ecosystem Approach

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23 Quantify the benefits Set goals based on the benefits Fish Production Nutrients + structure = food + shelter juv. survival growth How many fish do you want You need Z ha of oyster reef to get there Zu Ermgassen et al. Pub. Accepted, being revised, 2015

24 Small scale Conceptual diagram showing shell recycling, bagging, and placement in intertidal waters.

25 .to medium and large scale (Harris Ck. 377 acres

26 Example: Water Filtration Data type Value Unit Estuary volume xm 3 Estuary residence 38 days time Mean summer temperature* 30.7 C Data type Value Unit Extent oyster 2229 ha habitat Mean market 1 Ind m -2 oyster density Mean cull oyster 4 Ind m -2 density Mean market 94 mm oyster size Mean cull oyster size 45 mm Current filtration = ( )[ 1( e ( ( ))2 ) + 4( e ( ( ))2 )] missing filtration = filtration capacity wanted current filtration In this case = 1.22 x 10 9 L At a mean oyster size of 54mm we need 3.1 x 10 8 additional oysters. (or 1,532acres at 50/m2)

27 Example: Fish Production Gray Snapper: Lutjanus griseus How much reef do we need if we want 1000 individuals recruiting per year? At.01 ind/m 2 = 24.7 acres Fish entering the fishery? At 15.6 ind/acre = 64acres

28 The Science Behind It