390 likes | 513 Views
SALTWATER / BRACKISH-WATER AQ [objectives] Chapter 14. Discuss fundamentals of sw/bw AQ Identify and explain the kinds of facilities and sites ID and explain production considerations Discuss government regs Discuss culture of shrimp, salmon, mollusks, crustaceans and fish. FUNDAMENTALS.
E N D
SALTWATER / BRACKISH-WATER AQ [objectives]Chapter 14 • Discuss fundamentals of sw/bw AQ • Identify and explain the kinds of facilities and sites • ID and explain production considerations • Discuss government regs • Discuss culture of shrimp, salmon, mollusks, crustaceans and fish
FUNDAMENTALS • 15 states have shorelines on the Atlantic Ocean, 5 on the GOM, and 5 on Pacific • Saltwater and brackish-water aquaculture is called as mariculture • Salinity is the amount of salt in water • Salinity is measured either with a hydrometer, a refractometer, or a salinometer
SITES AND FACILITIES • Shore – land next to the ocean • Intertidal – area covered with water during high tide but not during low • Sublittoral – shallow inshore areas • Seabed – the ground always covered by the sea • Open ocean – away from shore
SHRIMP AQUACULTURE • Ideal for intensive cultivation • Grow rapidly in intensive facilities • Great product demand • Main species cultured: *brown shrimp *white shrimp *pink shrimp
SHRIMP brown white pink tiger
PRODUCING SEED • Gravid females must be captured or produced • Capturing larval shrimp from the wild is difficult • Baby shrimp are called nauplii and eat plankton • Postlarval stage lasts about 50 days • Production ranges from 1000-5000 pounds per acre
SALMON AQUACULTURE • Salmon are anadromous (live in saltwater; spawn in freshwater) • Salmon farming – fish are raised from fry in tanks, ponds, or cages • Salmon ranching – smolt are released in streams; they migrate to ocean; grow to adults and return to release stream to spawn
coho sockeye chum pink
MOLLUSKS • The oyster is the most important mollusk commonly cultured in the U.S. • Other cultured bivalves include clams, mussels, and scallops • Cultured gastropods include abalone and snails
BIVALVE MOLLUSKS oyster clams mussels scallops
OYSTER AQUACULTURE • Oysters change from males to females as they get larger • One female may release 50 to 100 million eggs per spawn • Eggs hatch within a few hours after fertilization • Turn into spat after 2 weeks and settle onto hard substrate (cultch)
OYSTER AQUACULTURE (cont’d.) • Oysters are filter feeders (plankton) • Commonly grown on seabed, trays, cages, rafts, and nets • Oysters require little management except for diseases and predators • Diseases include oyster fungus, dermo, and MSX • Predators include fish, seastars, and gastropods
OYSTER PREDATORS Oyster drill Cownose ray Sea star
HARVESTING • Oysters cultured on seafloor are typically harvested by tonging, dredging, or diving
GASTROPODS • Two gastropods are primarily cultured; abalone and snails (escargot)
OTHER CULTURED SPECIES • Lobsters • Blue crabs • Mullet • Milkfish • Pompano • Redfish • Cobia • Flounder • Grouper • Dolphin
LOBSTERS Maine lobster Florida spiney lobster