Extensive culture of burbot (Lota lota maculosa)

Jimmy Barron 1

Objectives

• Determine growth, condition, survival and optimal density for the extensive culture of burbot.

• Determine optimum temperature for growth, condition and survival for burbot transitioned to commercial feed.

• Evaluate existing natural ponds based on collaborations with Idaho Fish and Game.

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2008 extensive culture preliminary observations

• Six 12’ tanks, sunken into the ground were assigned to one of three treatments.

• Treatments were stocking time: 15 days on live feed(rotifers only), 30 days on live feed(rotifers only) and 45 days on live feeds(rotifers and artemia).

• 5000 larvae counted and stocked per tank.

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Intermediate data collection

• Water quality tested weekly.• Traps used to check for survival. • Lengths and weights recorded from trapped

burbot.

• Zooplankton sampling conducted weekly(beginning July 22).

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Results

• No survival from the 15d and 30d stocking times.

• 22 individuals harvested from the 45d stocking.

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-FW rotifers stocked

-Ceriodaphnia dubia Stocked

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-Daphnia magna stocked

Harvest

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45 d on live feed treatment burbot raised intensivelyMean endpoint mass(g) 5.6 0.4Mean endpoint length(mm) 98.8 31.5% growth(mm/month) 405% 119%growth(g/month) 1.55 0.381N 22 0% survival at 108d post stocking 0.22% 0%

45d treatment Intensive culture

Burbot mass

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Main points• Survival only found in tanks stocked with larvae fed for 45 days on rotifers and

artemia. Survival of 0.22%

• Burbot raised extensively had higher growth rates and survival than those raised intensively.

• Burbot density(d) was 5000burbot/6300L = .8 burbot per liter.

– At this stocking density in the proposed 10mx10mx2m experimental ponds(200,000L): 160k larvae(45days after first feeding) per pond would be needed, and the estimated harvest(0.22%survival) would be 352 juveniles per pond.

• This preliminary trial indicates that burbot can be successfully reared under these specific extensive conditions.

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Direction for 2009

• Stock at 45d post 1st feeding• Use density as the treatment.• Divide ponds in some way, thus increasing the

# of treatments and replicates.• Seed zooplankton first with freshwater

copepods and at a later time Daphnia magna.

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