Integrating basic and applied ecology using paired artificial natural reef systems.

Transcription

1 Integrating basic and applied ecology using paired artificial natural reef systems. Christopher D. Stallings 1, Kara R. Wall 1, Peter Simard 1, Jennifer E. Granneman 1, Kelly Kingon 2, and Christopher C. Koenig 2 1 University of South Florida, 2 Florida State University

2 Integrating basic and applied ecology using paired artificial natural reef systems. Ramblings about why we need to rethink the what, where and how we deploy artificial reefs Christopher D. Stallings 1, Kara R. Wall 1, Peter Simard 1, Jennifer E. Granneman 1, Kelly Kingon 2, and Christopher C. Koenig 2 1 University of South Florida, 2 Florida State University

3 Navigating Expectations & Charting Objectives

4 Navigating Expectations & Charting Objectives Expectations: a strong belief that something will happen predictive Objectives: a thing aimed at or sought; a goal Oxford Dictionary

5 FWC Artificial Reef Program Goals 1. Ensure that long term social, economic, and quality of life values of artificial reefs benefit the local and regional economies of Florida. 2. Utilize artificial reefs in scientific research to obtain a mechanistic and predictive understanding of how artificial reefs function ecologically and physically across spatial and temporal scales. 3. Use artificial reefs as a component of fisheries management. 4. Identify, procure and maximize new and existing sources of funding for artificial reefs. 5. Improve intergovernmental coordination and public/private cooperation in artificial reef development. 6. Foster public and private sector marine ecosystem stewardship and accurate understanding of artificial reef issues.

6 FWC Artificial Reef Program Goals 1. Ensure that long term social, economic, and quality of life values of artificial reefs benefit the local and regional economies of Florida. 2. Utilize artificial reefs in scientific research to obtain a mechanistic and predictive understanding of how artificial reefs function ecologically and physically across spatial and temporal scales. 3. Use artificial reefs as a component of fisheries management. 4. Identify, procure and maximize new and existing sources of funding for artificial reefs. 5. Improve intergovernmental coordination and public/private cooperation in artificial reef development. 6. Foster public and private sector marine ecosystem stewardship and accurate understanding of artificial reef issues.

7 FWC Artificial Reef Program Goals 1. Ensure that long term social, economic, and quality of life values of artificial reefs benefit the local and regional economies of Florida. 2. Utilize artificial reefs in scientific research to obtain a mechanistic and predictive understanding of how artificial reefs function ecologically and physically across spatial and temporal scales. 3. Use artificial reefs as a component of fisheries management. 4. Identify, procure and maximize new and existing sources of funding for artificial reefs. What are our expectations about how artificial reefs function ecologically and 5. Improve intergovernmental coordination and public/private cooperation in artificial reef development. as a component of fisheries management? 6. Foster public and private sector marine ecosystem stewardship and accurate understanding of artificial reef issues.

8 Florida s Artificial Reefs ~ 3000 reef complexes Various materials (concrete, metal, etc.) Various shapes (culverts, ships, army tanks, etc.) Various sizes Various configurations Various distances offshore (<1km >100km)

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10 What are our expectations about how artificial reefs function ecologically and as a component of fisheries management? Can we predict the ecological functions of artificial reefs given the wide variation in material, size, orientation, location, etc? Kinda sorta, not really High variance & dissimilarity even in controlled experimental systems What roles do artificial reefs have as a component of fisheries management? Unclear, there s an elephant in the room blocking the answer Rethinking how we deploy artificial reefs Before After Control Impact studies

11 Paired Art Nat Reef Studies in GOM sponge octocoral coral 12 Shallow (9-12m) Deep (23-30m) Block 1 10 Block 2 Block 4 Block 3 Number of Species Observed per Survey AR NR AR NR AR NR AR NR Block 1 Block 3 Block 2 Block 4

12 Experimental matrix of artificial & translocated coral reefs

13 Experimental matrix of artificial & translocated coral reefs Three reef types (natural, translocated, and artificial) Reef size, relief, complexity, and isolation controlled Natural patch reefs dispersed in area 1 meter

14 20+ years of Monitoring: Community Responses Natural Patch Reef Assemblage A Assemblage B Translocated Patch Reef Assemblage C Artificial Patch Reef Stallings et al. unpublished data

15 20+ years of Monitoring: Community Responses High variance & dissimilarity even in a controlled experimental system Natural Patch Reef Assemblage A Assemblage B Translocated Patch Reef Assemblage C Artificial Patch Reef Stallings et al. unpublished data

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17 Reef Size and Spacing More fish on larger reefs Colonization rates and residency influenced by interactive effects of reef size and spacing Gag selected shelter at the expense of growth Thus, mobile reef fishes could experience density dependent effects on growth, survival, and/or reproduction (i.e., demographic parameters) despite reduced stock sizes as a consequence of fishing. Lindberg et al. 2006

18 Location, location, location: Gag Young of Year Subadults Adults Offshore Direction on ontogenetic movements as fish grow and age Inshore

19 Location, location, location: Gag Young of Year Subadults Adults Artificial structures added inshore Offshore Direction on ontogenetic movements as fish grow and age Inshore

20 Location, location, location: Gag Young of Year Subadults Adults Artificial structures added inshore Offshore Direction on ontogenetic movements as fish grow and age Inshore

21 Location, location, location: Gag Young of Year Subadults Adults Artificial structures added inshore Offshore Direction on ontogenetic movements as fish grow and age Inshore

22 Location, location, location: Gag X Young of Year Subadults X X Adults Artificial structures added inshore Offshore Direction on ontogenetic movements as fish grow and age Inshore

23 Location, location, location: Red Snapper Mudrak & Szedlmayer 2012

24 What are our expectations about how artificial reefs function ecologically and as a component of fisheries management? Can we predict the ecological functions of artificial reefs given the wide variation in material, size, orientation, location, etc? Kinda sorta, not really High variance & dissimilarity even in controlled experimental systems How are artificial reefs a component of fisheries management? Unclear, there s an elephant in the room blocking the answer Rethinking how we deploy artificial reefs Before After Control Impact studies

25 What are our expectations about how artificial reefs function ecologically and as a component of fisheries management? Can we predict the ecological functions of artificial reefs given the wide variation in material, size, orientation, location, etc? Kinda sorta, not really High variance & dissimilarity even in controlled experimental systems How are artificial reefs a component of fisheries management? Unclear, there s an elephant in the room blocking the answer Rethinking how we deploy artificial reefs Before After Control Impact studies

26 Why the uncertainty? The uncertainty surrounding the value of artificial reefs ecologically or as a fisheries management tool has arisen for at least four reasons. 1. marine systems are notoriously variable and fish dynamics are affected by many factors. 2. many artificial reefs have been deployed without any predefined scientific program to study their effects 3. many investigations conducted so far have focused almost exclusively on the artificial reefs (e.g. their construction and attributes of the associated fishes), rather than on how nearby natural reefs may have been affected. 4. artificial reefs may simply affect distribution, by attracting fish from natural reefs and concentrating them upon artificial ones. Osenberg et al. 2002

27 Why the uncertainty? The uncertainty surrounding the value of artificial reefs ecologically or as a fisheries management tool has arisen for at least four reasons. 1. marine systems are notoriously variable and fish dynamics are affected by many factors. 2. many artificial reefs have been deployed without any predefined scientific program to study their effects 3. many investigations conducted so far have focused almost exclusively on the artificial reefs (e.g. their construction and attributes of the associated fishes), rather than on how nearby natural reefs may have been affected. 4. artificial reefs may simply affect distribution, by attracting fish from natural reefs and concentrating them upon artificial ones. Osenberg et al. 2002

28 Why the uncertainty? The uncertainty surrounding the value of artificial reefs ecologically or as a fisheries management tool has arisen for at least four reasons. 1. marine systems are notoriously variable and fish dynamics are affected by many factors. 2. many artificial reefs have been deployed without any predefined scientific program to study their effects 3. many investigations conducted so far have focused almost exclusively on the artificial reefs (e.g. their construction and attributes of the associated fishes), rather than on how nearby natural reefs may have been affected. 4. artificial reefs may simply affect distribution, by attracting fish from natural reefs and concentrating them upon artificial ones. Osenberg et al. 2002

29 Why the uncertainty? The uncertainty surrounding the value of artificial reefs ecologically or as a fisheries management tool has arisen for at least four reasons. 1. marine systems are notoriously variable and fish dynamics are affected by many factors. 2. many artificial reefs have been deployed without any predefined scientific program to study their effects 3. many investigations conducted so far have focused almost exclusively on the artificial reefs (e.g. their construction and attributes of the associated fishes), rather than on how nearby natural reefs may have been affected. 4. artificial reefs may simply affect distribution, by attracting fish from natural reefs and concentrating them upon artificial ones. Osenberg et al. 2002

30 Why the uncertainty? The uncertainty surrounding the value of artificial reefs ecologically or as a fisheries management tool has arisen for at least four reasons. 1. marine systems are notoriously variable and fish dynamics are affected by many factors. 2. many artificial reefs have been deployed without any predefined scientific program to study their effects 3. many investigations conducted so far have focused almost exclusively on the artificial reefs (e.g. their construction and attributes of the associated fishes), rather than on how nearby natural reefs may have been affected. 4. artificial reefs may simply affect distribution, by attracting fish from natural reefs and concentrating them upon artificial ones. Osenberg et al. 2002

31 What are our expectations about how artificial reefs function ecologically and as a component of fisheries management? Can we predict the ecological functions of artificial reefs given the wide variation in material, size, orientation, location, etc? Kinda sorta, not really High variance & dissimilarity even in controlled experimental systems How are artificial reefs a component of fisheries management? Unclear, there s an elephant in the room blocking the answer Rethinking how we deploy artificial reefs Before After Control Impact studies

32 Assumption: more reefs = more fish Bohnsack 1989

33 Assumption: more reefs = more fish Bohnsack 1989

34 Production can be high on artificial reefs

35 We STILL don t understand the relative effects of production vs. attraction Bohnsack 1989

36 Influences on the relative effects of production vs. attraction Species specific Region specific Bohnsack 1989

37 Influences on the relative effects of production vs. attraction Species specific Region specific Boaters/fishermen in egom use art reefs up to 150x more than nat reefs Bohnsack 1989

38 What are our expectations about how artificial reefs function ecologically and as a component of fisheries management? Can we predict the ecological functions of artificial reefs given the wide variation in material, size, orientation, location, etc? Kinda sorta, not really High variance & dissimilarity even in controlled experimental systems How are artificial reefs a component of fisheries management? Unclear, there s an elephant in the room blocking the answer Rethinking how we deploy artificial reefs Before After Control Impact studies

39 What are our expectations about how artificial reefs function ecologically and as a component of fisheries management? Can we predict the ecological functions of artificial reefs given the wide variation in material, size, orientation, location, etc? Kinda sorta, not really High variance & dissimilarity even in controlled experimental systems How are artificial reefs a component of fisheries management? Unclear, there s an elephant in the room blocking the answer Rethinking how we deploy artificial reefs Standardized impact studies Before After Control Impact studies

40 Before After Control Impact (BACI) Proposed New Artificial Reef

41 Before After Control Impact (BACI) Natural Reef(s) Proposed New Artificial Reef

42 Before After Control Impact (BACI) Natural Reef(s) Proposed New Artificial Reef These are the impact sites

43 Before After Control Impact (BACI) Natural Reef(s) Proposed New Artificial Reef These are the impact sites Natural Reef(s) No New Artificial Reef These are the control sites

44 BACI: Impacts of new artificial reef on natural reef(s) Deployment of new artificial reef Biomass / abundance / richness Non impact Control New Art Reef 1 2 years Before new reef 1 2 years After new reef

45 BACI: Impacts of new artificial reef on natural reef(s) Deployment of new artificial reef Biomass / abundance / richness Impact Reef (w/o A) Non impact Control New Art Reef 1 2 years Before new reef 1 2 years After new reef

46 BACI: Impacts of new artificial reef on natural reef(s) Deployment of new artificial reef Biomass / abundance / richness Impact Reef (w/o A) Non impact Control New Art Reef Impact Reef (w/ A) 1 2 years Before new reef 1 2 years After new reef

47 BACI: Impacts of new artificial reef on natural reef(s) Biomass / abundance / richness Deployment of new artificial reef No/weak Attraction Strong Attraction Impact Reef (w/o A) Non impact Control New Art Reef Impact Reef (w/ A) 1 2 years Before new reef 1 2 years After new reef

48 Take home points We are currently navigating expectations in rough and unpredictable seas BACI studies should be required for ALL future artificial reef deployments Improved predictive power The only way to finally get a handle on attraction production

49 Thank you FWC Artificial Reef Program Especially Bill Horn (retired), Jon Dodrill, & Keith Mille Many, many volunteer divers