Totem Oysters
Totem Oysters (Totem) is one of British Columbia's few remaining family farms and is currently raising Pacific salmon, rainbow trout, a small number of sablefish and Pacific oysters.
Totem Oysters’ project focused on using closed containment net-bag systems at a site located in St. Vincent Bay, Jervis Inlet, to produce a variety of species including Pacific salmon, rainbow trout, sablefish and Pacific oysters.
The location of this pilot was in an area prone to plankton blooms, and the focus was on determining if the closed containment system would increase the level of control over water quality parameters. The expectations were that improved water quality would translate into higher stock survival rates, and therefore increased harvest levels, which would offset the higher costs associated with this production system.
Waste recovery was another aspect of the Totem pilot. Totem retrofitted its bag-cage system to incorporate a waste recovery capacity, with captured wastes analyzed for their suitability as commercial fertilizer. A final dimension to this project was the use of organic salmon aquaculture feed and fish that are Certified Disease Free (in accordance to Canadian Fish Health Regulation standards).
- The collection and recovery of salmon feces and excess feed will reduce the magnitude of benthic impacts at this farm site. The performance measures listed below will look at differences in waste impacts between the conventional and experimental technologies and relative to baseline data.
Chemical:
Total volatile solids or total organic carbon;
Hydrogen sulphide and
Redox potential
Biological:
Species diversity;
Species density and
Species assemblages.
Physical:
Measured weight of recovered waste using sediment canisters and
Direct measures of recovered waste.
- The impermeable nature of the closed containment rearing system may provide additional environmental benefits that are not as readily measured. Potential benefits include reductions of interactions between farmed stocks, wild stocks and marine mammal predators. Benefits that may be associated with the Certified Disease Free smolts and which may accrue from reduced pathogen loads and increased disease resistance include higher growth rates and reduced likelihood of transfer to wild stocks. Performance measures include:
Fish health:
Visual mortality inspections and record and Pathogen load and
Frequency of disease outbreaks.
Escapes:
Accuracy of inventory and
Presence/absence of holes
Predators:
Visual mortality inspections and records and
Observations of the operator.
- Evaluation of the economic viability of this project will include a comprehensive review of production costs and other key factors such as infrastructure costs, durability and hydro costs.
- Key biological performance measures will include growth rates, conversion rates, rearing densities and survival. These performance measures will reflect in part some unique characteristics of the closed-containment technologies including a variable depth intake pipe that can be used to select from zones where water temperatures and plankton conditions are favourable.
Pictures of Totem facilities in Jervis Inlet. (click for larger image)
Pilot project suspended operation in Fall 2002.
Updated: April 18, 2005
