Bill Dewey presentation on ocean acidification

Preliminary lessons from the oyster “seed crisis” What can the rest of the seafood industry learn from the first producers to suffer (and partly overcome) severe impacts associated with “corrosive” high-‐CO2 seawater? Taylor Shellfish hatchery on Dabob Bay, Washington By Brad Warren

Taylor & Whiskey Creek •  TAYLOR SHELLFISH FARMS: Largest U.S. shellﬁsh grower. ~12,000 acres under culOvaOon (owned or leased) in Washington, Mexico, BriOsh Columbia, a pearl farm in Fiji. Two company-‐owned hatcheries (Hawaii, Washington) supply its own farms. •  Whiskey Creek Shellﬁsh Hatchery: largest oyster seed supplier on West Coast, supplies ~75% of farms. •  Together, they provide lion’s share of producOon on West Coast.

Oyster seed crisis arrives Paciﬁc oyster larvae fail L: Paciﬁc oyster larvae growing at Taylor. Billions of these were lost. R: Larval clams dissolve at pH 7.5 in lab (Green) 70-‐80% loss of producOon in 2007-‐2008 at both major hatcheries. At Whiskey Creek, oyster larvae dissolved, vanished in tanks. Even hard-‐fouling of intake pipes ceased. Li]le or no commercial-‐scale wild “set” of oysters in Willapa Bay since 2005. Industry hunts for culprits: vibrio tubiashi?

Paradigm shiH Feely et al 2008 Researchers at Whiskey Creek (Barton, others) conﬁrm strong link to larval death.

How hatcheries rebounded (for now) •  Whiskey Creek is near peak producOon levels through July 2010, by dodging frequent episodes of “bad water,” working overOme to produce in “good water” periods. •  Taylor also going strong through July 2010, enjoying “good water” from shallow intake (30 d); but deep intake (100 d) now yields high CO2 levels that they avoid. •  Two criNcal tools enabled this rebound:

1. Monitoring & research If you can see what’s coming at you, you can dodge New monitoring systems, OOS buoys permit frequent sampling of water quality parameters (e.g. pCO2, pH): Hatcheries avoid spawning in high-‐CO2 water. Bioassays, calciﬁcaOon studies, physiological & geneOc analyses underway at several labs.

1. A well-‐defended posiNon Hatcheries Control of most vulnerable life-‐ stage enabled them to defend larvae < 120 microns.

Industry’s three-‐Phase response 1)  Short term: monitoring & research enable producers to dodge “bad water.” (operaOons + policy) 2)  Medium term: culOvate more resilient broodstock. (operaOons + policy) 3) Long-‐term: promote policies to reduce emissions, strengthen research & monitoring (policy)

STEP 1 Monitoring in order to avoid exposure to “bad water.” Sensors: pH, T, S, depth, turbidity

pCO2 readout at 100 d: ~1,000 ppm Taylor’s deepwater intake: pH here measured ~ 7.5 At Whiskey Creek, pCO2 is now key predictor of larval survival. For gigas larvae in ﬁrst 2 days, hatchery owners say 200-‐300 ppm is opOmal, with low end best; older larvae can handle up to 400 ppm. “Over 600 we back oﬀ.” (Wiegardt, pers. comm with BW 7.27.2010)

pCO2 at 30 d: 332 ppm Taylor’s shallow water intake: pH here measured ~8.2 To avoid high CO2 water, Taylor mainly now relies on shallow intake for oysters. This increases exposure to algal blooms, etc, which were the reason they developed a deepwater intake at 100 d. Now elevated CO2 is pushing Taylor to risk that exposure, esp. for young Paciﬁc oyster (c. Gigas)

Managing around the problem SPAWN! •  Put small larvae into tanks ﬁlled in the aHernoon or overnight -‐ Works if the sun is out •  24 hour noOce-‐ Upwelling takes a day or two to start up, so when winds from the North, ﬁll tanks late in the day and spawn like crazy DON’T Slide: Alan Barton SPAWN!

Step 2: breeding for resistance Broodstock research has increased oyster yield in the past (see graph): Can it help now? Molluscan Broodstock Program at OSU increased oyster yield (sum of survival + growth) by 41% over 2 generaOons. Can broodstock work boost resistance to high CO2? Preliminary signs of promise: a few families show be]er resistance; OSU MBP some species too (Olympia). Growth rates, yields, quality?

Step 3: Policy engagement •  Key aims : Support research & monitoring, protect producOvity. •  Oyster producers talk to Congress about acidiﬁcaOon, need for research; some support prevenOve emissions-‐reducOon policies. •  Sen. Cantwell secures $500,000 for hatchery retroﬁts, including monitoring. •  HR 989: Taylor & others worked it, got 58% yes vote. •  OOS systems beginning to monitor pCO2 etc,

ImplicaOons for seafood industry •  ProducNve zones are most vulnerable: highly enriched seawater  closer “Opping points.” •  First blow can hit hard: 70-‐80% loss of producOon in 2007-‐2008 at two major hatcheries (supplying lion’s share of producOon). •  Technical and poliNcal savvy allowed shellfish industry to meet the challenge: Taylor, Whiskey Creek found ways to dodge impacts, win needed scienOfic & poliOcal support, and rebuild producOon (for now). Other growers, reliant on Whiskey Creek, pitched in. PoliOcians too. (3 Congressmen a]ended our workshop in March). •  Impacts are uneven: Species, families, & local environmental condiOons can either miOgate or aggravate effects. •  Victory probably temporary: ConOnued rise in emissions  more trouble ahead: more severe acidificaOon, likely wider impacts.

Thanks. •  Benoit Eudeline & Bill Dewey at Taylor Shellﬁsh Farms. •  Mark Wiegardt, Sue Cudd, Alan Barton at Whiskey Creek. •  Richard Feely, Vicky Fabry, Joanie Kleypas, Jeremy Mathis, Sco] Doney, Mark Green, Jeﬀ and many others. •  Bulli] & Oak foundaOons, Rockefeller Brothers Fund, other donors.

Bill Dewey presentation on ocean acidification

by Northwest Indian Fisheries Commission on Aug 13, 2010

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Bill Dewey presentation on ocean acidification — Presentation Transcript

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