Cockle/Oysters Flashcards
scientific name for cockle
Clinocardium nuttallii
why cockles?
- indigenous
- culturally important
- attractive product
- local market
- world markets
- multiple markets
- different grow-out strategies
what sort of areas do cockels grow?
sandy, sheltered beaches
describe a cockels shell
distinctively rounded shells
bilaterally symmetrical
heart-shaped
radial ribs
cockle’s mantle has 3 appertures:
- inhalant
- exhalent
- pedal
gonochorism
sex varies with conditions (cockle)
Name pros for BC cockle aquaculture
- fastest potential growth rate of any species under consideration
- can be grown off bottom at high densities with great survival
- good response to aquaculture growing conditions
- wide range of physical tolerances
- internationally recognized
- idiginous cultures attachment
- attractive animal
- food quality
- taste
- lack of competition
how long does it take a cockle to get to ‘steamer’ product, sushi product?
1 season
2 seasons
cons for cockle aquaculture
- market establishment and vertical integration
- short shelf life
- dangerous fishery (21 ppl died..)
what are the 4 steps for shellfish culture?
hatchery, nursery, grow-out, market
what is in a hatchery?
- broodstock
- larvae
- settle
- algae
what sort of tanks do you hold cockle larvae in?
upwelling larval rearing tanks, downwelling seed tanks
name considerations for broodstock with shellfish aquaculture
-why are the brood important
-where do you get them from
-how many do you use
-sexual type matter?
(protrandic and functional hermaphrodites, alternate)
-benefits of conditioning
-temperature matter?
-food needed?
-season?
name some larval food determinations when setting up a shellfish hatchery
- suitable dietary items for larvae and post larvae
- optimal food ration for larvae and post larvae
- optimal rearing temp for larvae and post larvae
- optimal stocking densities of r larvae and post larvae
what are some potential hatchery problems when rearing shellfish?
Factors affecting growth/survival:
-temp, salinity, seawater quality, tolerances outside of wild range, egg/larval quality, disease (bacteria, response)