By Charlotte Tarver–A three-year pilot project investigating the feasibility of developing shellfish farms on Haida Gwaii is drawing to a close.
The Haida Fisheries project monitored shellfish growth and survival rates, tested different growth techniques and looked at where shellfish grow best. The project also did an analysis of the potential market for locally farmed shellfish.
Four species were initially chosen for the project: Pacific oyster, Mediterranean and blue mussels and the Pacific or Japanese scallop. All are non-native species to island waters.
“We decided not to study oysters as there is already an established private oyster farm on the islands.” said Bart DeFreitas, Program Biologist for Haida Fisheries. Pacific oysters are also the most widely cultivated shellfish species in the world with a number of established commercial farms in B.C.
Mussel and scallop spat (seed) were planted in 2003 at six sites in Rennell Sound, Naden Harbour and Skidegate Inlet. After looking at the logistics of moving crews, it was decided that Kagan Bay in Skidegate Inlet would be the best site for the project.
Two deep-water growing techniques were used: a long line suspended from a series of floats with trays or nets attached to the line; and a raft with trays or nets hung under it.
“The mussels didn’t survive heavy predation by sea stars. It was pretty easy for them to get in the trays and a couple of sea stars would eat all the mussels,” according to Mr. DeFreitas.
The focus then shifted to studying the Japanese scallop. It’s a large species and there are few large scallops on the market. It has a good survival rate and does not require feeding. No antibiotics are needed and the shells deter predators. However, scallops are susceptible to ‘bio-fouling. That’s when kelp, sea stars, sea cucumbers and other species attach to the shells. To lessen bio-fouling, growing trays need to be below 10 metres. To remove bio-fouling requires a labour-intensive cleaning process.
The main criteria for scallops to grow into an edible-size is: clean water, good salinity levels and oxygenation, and no stagnant zones. Scallops grow best at depths of 5 – 15 C. Optimal growth occurs when trays are hung at least 5m below the surface to avoid freshwater and warmer water.
“Growing scallops would be a very nice, sustainable business that promotes clean water, advocates for decreasing freshwater run-off and good sewage treatment,” said Mr. DeFreitas, “It appeals to First Nations and local coastal communities.” The Pacific scallop was first introduced into BC waters in the 80’s.
“The species has the potential for colonizing in the wild, but none have been detected so far,” continues DeFreitas.
One of the biggest problems facing commercial shellfish farms is the threat of PSP. To lessen the chance of PSP outbreaks, shellfish would be harvested in winter, when natural biotoxin levels are down. PSP testing is done here weekly in the summer and twice monthly the rest of the year. The samples are sent to Vancouver. All shellfish are tested before distribution.
Currently, fresh farmed scallops and oysters are available locally with the oysters from a private farm in Skidegate Inlet.
“We don’t sell a lot of them, but we are the only place in town to buy local farmed shellfish. Oysters sell better, but they are cheaper than scallops.” Vivian Pattison, Isabel Creek Store in Queen Charlotte.
initial stages of securing the shellfish farm sites legally are underway. A shellfish farm maximum operation size would be 10 acres and would employ 12 people per farm, full time.
The project is a joint venture between 10 First Nations groups on the north coast. Their vision is to share a processing facility and the marketing plan. To develop commercial farms, will need “deep pocket” investors as needs expensive equipment and is an 18 to 24 month wait for scallops to develop their size.
“Haida Fisheries are transitioning into the next phase of finding investors. Even though we have been doing all the data collecting and monitoring – it now moves to the Old Massett and Skidegate bands to get investors and into production,” said Mr. DeFreitas.
“At the tail end of the research, once the scallops are big enough in the pilot sites, we’ll harvest them when ready and give away at feasts – like the recent CHN House of Assembly feast.”
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