|
Grow-out Method |
Deployment Area |
Equipment Required |
Advantages |
Disadvantages |
|
Raft System Surface or Submersible |
Deep water |
Boat tender Floating raft using one of these: Oyster sticks, lantern cages, stacking Dark Sea Trays of Aquatech trays |
Longer lasting and less maintenance than longlines Stable work surface Easily moved to changing site conditions For maximum growout potential highest return on amortized investment |
Totally under water more fouling occurs Slightly higher capital cost |
|
BST Aquaculture Adjustable Long-line Method |
Subtidal |
Special Veclock long line Wood pole pilings, riser clips, bag clips, Durethene Grow-out bags Boat tender |
Low labour Mother Nature does most of the work - bio-fouling control, shell pruning, adjustable food supply, very efficient Inexpensive Cages have reinforced strands that give rigidity in height and depth and allows water circulation for feeding, UV stabilized, long lasting |
Site specific Longer initial set up time Can not be used in major icing areas |
|
Floating Surface / Subsurface |
Sub-tidal Any deep water application Especially designed for areas with ice in the winter |
ADPI - OBC Cages Lobster trap rings, Styrofoam SM, Black plastic cable ties, hog rings, longline-size dependent on number of bags, anchors, spreader bars or wood |
Low-fouling Can be used from nursery to full grow-out; for nursery fine mesh spat collection bags inside the OBC cage is used until optimal growth is achieved In the winter in ice areas system can be easily submerged Cages have reinforced strands that give rigidity in height and depth and allows water circulation for feeding, UV stabilized, long lasting More rapid growth than other methods because of the increased food availability nearer the water surface Easy to deploy and move Inexpensive |
Semi-labour intensive Limited to quiet sites Limited site efficiency Subject to rough water Harder to harvest |
|
Bottom Culture (Ranching) |
Ocean floor |
Boat and dragger |
Uses existing equipment Very little fouling control problems |
labour intensive, predation exposure High equipment cost More susceptible to disease such as MSX and Dermo |
|
French Method Above ground racks |
Tidal flats Low tide out of water |
Rebar Racks ADPI - OBC or CBC cages Hog rings Bag pins Tractor / ATV - trailer |
Cages are reusable Low tide the bags are out of the water less fouling occurs Oyster are protected from predators, sinking, and wash outs Cages have reinforced strands that give rigidity in height and depth and allows water circulation for feeding, UV stabilized, long lasting No boats required can use ATV or small tractor with trailer for deployment and harvest |
labour intensive Oysters can not feed when out of water Oyster is stressed when out of water Slower grow-out compared to other methods |
|
Modified French Method Bottom Racking |
Sub-tidal Low-tide remain in water |
Steel Bottom Racks ADPI - OBC Cages Hog Rings bag pins Boat Tender with Deployment / Harvest boom or crane |
Cages are reusable Oysters are protected from predators, sinking, and wash outs Cages have reinforced strands that give rigidity in height and depth and allows water circulation for feeding, UV stabilized, long lasting More rapid growth than above ground rack methods because of the increased food availability nearer the water surface |
Cages and racks are always under water causes major fouling labour intensive Harder to work with them above ground racks Site specific |