Increasing CO 2 and Ocean Acidification

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1 Increasing CO 2 and Ocean Acidification CO 2 + H 2 O HCO H CO Mauna Loa atmospheric CO 2 oceanic CO ph ph Year Feely et al At 1000 ppm CO 2, ph ~7.7

2 ph and Acid-Base Balance ph seawater = 8.1 H + ph internal = 7.5 internal ph homeostasis seawater ph

3 Changes in Inorganic Carbon Distribution Preindustrial CO 2 Used for photosynthesis CO 3 2- Used for CaCO 3 hard parts - corals, mollusks, etc 200

4 Effects of OA on Calcification Today [CO 3 2- ]=320 μm ~ 2100 [CO 3 2- ]=140 Favia fragum ~2300 [CO 3 2- ]=80 [CO 3 2- ]=20 Cohen et al C. Vernon

5 Effects of CO 2 on photosynthesis Relative Photosynthesis (%) Natural Assemblages CO 2 (µatm) Hein and Sand-Jensen 1997 Photosynthesis Trichodesmium CO 2 (µatm) Hutchins et al. 2008

6 Ocean Acidification in Relationship to Southeast Atlantic Fisheries Patrick Geer, Chief of Marine Fisheries Georgia Department of Natural Resources SOCON August 18,

7 Whelk Fisheries Possibly Impacted by Lower ph Oysters and Clams media.hamptonroads.com Spiny Lobster Cannonball Jellyfish Blue Crab White Pink Brown Penaeid Shrimp seagrant.noaa.gov 2

8 Average Annual Commercial Harvest by State Top 15 Species (in millions of lb) Rank NC SC GA FL - East Total CRAB, BLUE CROAKER, ATLANTIC SHRIMP, BROWN SHARK, SPINY DOGFISH FLOUNDER, SUMMER BLUEFISH FLOUNDER, SOUTHERN MULLET, STRIPED (LIZA) MENHADEN SHRIMP, WHITE SHARK, SMOOTH DOGFISH MACKEREL, SPANISH SWORDFISH SPOT OYSTER, EASTERN CRAB, BLUE SHRIMP, WHITE SWORDFISH SHRIMP, BROWN SHRIMP, MARINE, OTHER OYSTER, EASTERN SNAPPER, VERMILION SHAD, AMERICAN FINFISHES, UNC GENERAL GAG SEA BASS, BLACK CLAM, NORTHERN QUAHOG SCAMP LEATHERJACKETS DOLPHINFISH CRAB, BLUE SHRIMP, WHITE SHELLFISH JELLYFISH SHRIMP, BROWN SHRIMP, MARINE, OTHER FINFISHES, UNC GENERAL CLAM, QUAHOG CRAB, BLUE, PEELER SHAD, AMERICAN OYSTER, EASTERN FINFISHES, UNC FOR FOOD CRAB, BLUE, SOFT SNAILS (CONCHS) CRAB, FLORIDA STONE CLAWS SHRIMP, WHITE MACKEREL, SPANISH MACKEREL, KING AND CERO CRAB, BLUE SHRIMP, ROCK MULLET, STRIPED (LIZA) SHRIMP, BROWN SWORDFISH CRAB, DEEPSEA GOLDEN SHRIMP, PINK SHRIMP, ROYAL RED AMBERJACK, GREATER TILEFISH, GOLDEN LOBSTER, CARIBBEAN SPINY KING WHITING CRAB, BLUE SHRIMP, WHITE SWORDFISH SHRIMP, BROWN SHRIMP, MARINE, OTHER OYSTER, EASTERN SNAPPER, VERMILION SHAD, AMERICAN FINFISHES, UNC GENERAL GAG SEA BASS, BLACK CLAM, NORTHERN QUAHOG SCAMP LEATHERJACKETS DOLPHINFISH

9 Harvest by State Source: NMFS Research Surveys Source: GADNR 4

10 Penaeid Shrimp 1. Spawning offshore (May June). 2. Eggs hatch within 24 hrs. 3. Naupli develop thru 5 stages 2 days. 4. Protozoea develop thru 3 stages over 7 days 5. Mysis has 3 stages 6. Postlarva (2 stages) rides flood tides up into the creeks. 7. Juveniles grow quickly and move into the sounds as they grow. 8. Adults migrate offshore to spawn Total Life Cycle: 6-8 months days in ocean 5

11 Harvest by State Source: NMFS Research Surveys Source: GADNR 6

12 Blue Crab Life Cycle Mate upriver MARCH August Females migrate down river carrying egg mass 2 weeks Eggs are released in clean, high saline waters in ocean Larvae go through two stages and 8 molts and are transported back to the estuary. Larvae settle and juveniles migrates into the marshes Total Life cycle: years days in ocean 7

13 Potential Impacts of Ocean Acidification Greater with calcifying (CaCO 3 ) organisms (mollusks, echinoderms, crustacean) Marine organisms typically more at risk than estuarine species, slow growing, less mobile species more susceptible Early life stages (eggs and larvae) may be at highest risk Generalized Impacts of lower ph Calcification Growth Reproduction RECRUITMENT Survivability / Mortality 8

14 Specific Impacts on Crustaceans Not consistent across the phylum. Calcification: Increases lobsters, crabs, and shrimp create thicker shells BUT. This has a metabolic cost in the long term Reduced condition index less meat, less value to fishery Growth: Decreased Longer inter-molt period Smaller growth increment Prolonged period of ecdysis (soft-shelled) Reproduction Smaller at maturity less fecund 9

15 Specific Impacts on Crustaceans pg2 Recruitment: Reduced Eggs and larvae development compromised slower growth Survivability/Mortality: Smaller size - more vulnerable to predators Predators not satiated eat more Changes in the plankton community: Food quality and quantity (copepods, amphipods) Timing match/mismatch Predation other zooplankton and high order species 10

16 Questions? 11

17 12

18 Management Implications of OA for Fisheries, and a question Identified OA management issues include: - Shellfish, crustaceans, corals impacts on larval development and shell production - Fish- Potential secondary impact from reduced food organisms The question: Can water quality improvements and seagrass recovery assist in providing OA refugia in estuaries?

19 Tampa Bay nitrogen load decreased by 50%

20 Seagrass Recovery Goal Met Data: SWFWMD

21 Long-term ph measurements indicate increases with seagrass recovery

22 Tampa Bay OA Monitoring Collaboration LOCAL: Water quality Environmental Protection Commission of Hills. County 100 fixed long-term water quality stations (1972-present) REGIONAL: Seagrass extent Southwest Florida WMD Aerial surveys every 2 years (1982-present) STATE: Molluscs, HABs, Fish Florida Fish and Wildlife Conservation Commission Random sites 1990-present FEDERAL: Sediment cores USGS ( )

23 Ongoing Research USGS, FWRI, TBEP examining the role of seagrass beds in elevating ph and carbonate mineral saturation state in Tampa Bay

24 Ocean Acidification the Southeastern Bivalve Industry

25 Defining the bivalve industry in the Southeast U.S. the number of hatcheries by state South of Virginia 1- Louisiana 1- A labama 8- Florida 1- Georgia 1- South Carolina

26 regional industry in regards to Ocean Acidification? What do we know? Have we done any testing? What is planned?

27 looking at Ocean Acidification? - It has been a defined problem with hatcheries in other regions - Economically the bivalve industry in the Southeastern U.S. is worth 100 s of millions of dollars. - Bivalve larvae along with other sensitive invertebrates represent the Canary in the Coal Mine

28 History of unknown diseases and mortality in bivalves

29 What are other regions in the world doing?

30 What should we be doing? Text