Seed Collection for Offshore Mussel Farms in RI and SNE
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Transcript of Seed Collection for Offshore Mussel Farms in RI and SNE
Scott Lindell, DirectorScientific Aquaculture ProgramMarine Biological LaboratoryWoods Hole, [email protected] 508/289-1113
Seed Collection for Offshore Mussel Farms in RI and SNE
Cooperators –• PI, Scott Lindell, MBL Woods Hole
Bill Silkes, American Mussel Harvesters, Salt Water FarmGreg Mataronas, Mike Marchetti, Sakonnet MusselsRick Karney, Alec Gale, Martha’s Vineyard Shellfish Group.Rich Langan, Ken La Valley, UNH extensionDale Leavitt, Roger William University, extension and res.
Challenges of supply
• Consistent seed supply important for consistent market– 1 meter of collector rope for every 2 meters of grow-out
rope “rule of thumb”
• Choosing best time to set out– Global weirdness making it less predictable
• Can work with other aqua-gear for supply
MARINE BIOLOGICAL LABORATORY
• Best to collect local supply with spat collecting rope– $1.50/m for NZ rope, check out Bioprocess rope, or use old potwarp– Spatfall in March - June and again in Fall
• Once lines established, one-half or more of seed needed can be recovered as overset when grading market mussels.
• Seed grading is an important process for uniform product
Mussel Seed
Types of seed collectors
Rhode Island made!
New Zealand Xmas tree
Spanish ropes
UNHcollector
Collecting mussel seedMarch 2012
October 2012
Seed grew at 5 to 6mm/month in Menemsha Pond
Seed Quality Bottom vs. rope collected
Declumped and gradedClumped
Preliminary MBL hatchery trialsWound up rope in tank set up
1 to 3 mm spat in 2 monthsPlanted in May. December seed > 20mm>3mm/month growth rate
Coir rope as a “temporary” attachment platform prior to socking
Closed or "Restricted" Waters• Most classifications are due to bacterial contamination (fecal coliform) not
"poisonous or deleterious substances"
• Studies support depuration times as short as 2 weeks at temperatures above 50 degrees F.
• Most regulators want to ensure time/temperature regimen of one month at 50 degrees F.
• Most States allow for 6-month depuration time (simply to cover all species and times of the year).
• RI currently imposes 12-month depuration time (to allow opportunity for relayed shellfish to spawn).
Closed Waters and Mussels• Mussel seed can be scarce resource - best collected in water
column on "collectors".
• Closed waters are good location for collecting seed - doesn't interfere with other shellfishing or approved growing use
• Mussels are some of the best filterers even at low temperatures so successful depuration is short.
• Reducing relay and depuration time for mussel seed to 6-months or less makes good biological and economic sense.
Acknowledgements
• Funding from Rhode Island Sea Grant, and Northeast Regional Aquaculture Center Research Assistants – Emma Green Beach and Bill Rathjen
• MBL Interns: Hilary Ranson, Molly Peach, Morgan Beals, Charlotta Jornlid