triploid oysters

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Transcript triploid oysters

Oysters
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Eastern oyster (Crassostrea virginica):
European (flat) oyster (Ostrea edulis):
Kumamoto oyster (Crassostrea sikamea):
Olympia oyster (Ostrea lurida):
Pacific oyster (Crassostrea gigas):
Olympia oyster (Ostrea lurida
• The Olympia oyster is found from Alaska to Baja
California, although Washington is the only state
that has produced Olympias on a commercial
scale. Overfishing and pollution have reduced
catch levels to less than one percent of former
levels. A few growers in Washington state have
had some success farming Olympias, but
production remains limited.
Pacific oyster (Crassostrea gigas)
• Comprises 98 percent of world farmed oyster
production. Native to Japan, it is now farmed
extensively in Washington state, British
Columbia, Europe, and the Pacific Rim. Most
growers use hatchery seeds and raise the oysters
on the ocean bottom or on trays or ropes
suspended in the water column.
Purchase and Storing Tips
• If stored at 36-40 degrees F in a moist
environment, oysters can be kept up to two weeks
after they are collected, however, shelf life is
shorter after spawning in the summer.
• As a rule, Olympia oysters command the highest
price, followed by European oysters, Kumamotos,
Pacific oysters, and Eastern oysters.
• By law, a live-oyster shipment must include
identification of the oysters' origin and collection
date; it is illegal to discard this tag sooner than 90
days after delivery.
PRODUCT FORMS:
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LIVE. SHUCKED MEATS: Graded:
Petite (250-400/gal.),
Extra Small (145-250/gal.)
Small (96-144/gal.)
Medium (64-95/gal.)
Large (64 and under)
FROZEN: IQF meats and on the half shell
SMOKED meats
BREADED
YIELD:
• 5-14%, depending on species and time of
year (meat yield is lower after spawning).
SIZE RANGE:
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In shell: Pacific oysters—2 1/2 - 7 inches,
Eastern oysters—3 - 5 inches
Kumamotos—2 1/2 -3 inches
Olympia oyster—1/2 - 1 inch
European flat oyster—3 - 4 inches
Meats: 2/10 of an ounce to 2 ounces.
MARKET NAME(S):
• In shell oysters marketed under various
regional names (Blue Points, Hama Hamas,
Wellfleets, Snow Creeks, Fanny Bays, Icy
Bays, Hog Island, Pearl Bay etc.) or by
species name (Olympias, Flats, Kumamotos
etc.)
WASHINGTON IN BRIEF
Statistics
• Top 5 Agricultural Commodities (2002)
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CommodityValue of receipts (thousand $) Percent of U.S. value
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Apples
Dairy products
Cattle and calves
Potatoes
Wheat
Oysters
977,508
671,040
614,385
478,166
475,718
30,500
63.3%
3.3%
1.6%
5.8%
8.6%
70.%
Shellfish Nursery Rearing Systems
1: Oyster Seed on Cultch
• Seed that has successfully settled on shell or tubes
is moved from setting tanks to nursery areas.
• Nurseries can be intertidal or subtidal.
– Rearing oyster seed on an intertidal beach hardens the
seed, reduces predation and fouling but steps must be
taken to prevent seed drying or being damaged by
intense sunlight when it is exposed to the air between
high tides. Intertidal nurseries are usually between the
1.5 and 2.5 meter level.
Growing algae in
special indoor tanks
Nursery Systems: Upwellers for
Clam and Single Oyster Seed
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Outdoor setting
tanks at the
hatchery
Harvesting
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Harvesting
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TRIPLOID OYSTERS
Triploid Oysters are a new type of oyster produced during hatchery spawning by increasing
the number of chromosomes, the genetic material found in all living things.
THE "ALL-SEASON OYSTER"
Triploid Oysters have two important advantages over Diploids during their life cycle. In the
Summer months when regular Diploid Oysters are spawny, Triploids remain firm, full and
sweet. And they maintain this quality during the Fall, when spawned-out Diploid Oysters are
watery and reduced in mass.
THE WORLD'S LARGEST OYSTER HATCHERY
To meet our growing need for consistent, high quality
oyster larvae and seed, we developed our own
Quilcene, WA hatchery beginning in 1978. Here,
advanced technology, experienced technicians, and a
superb natural environment have combined to make it
the world's largest, with a capacity in excess of 30
billion oyster larvae per year. This same quality is now
available to provide other growers worldwide with a
variety of oyster and clam species, plus algae feeds,
and various support services.
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