- Animals: shellfish
- Animal Production: housing
- Education and Training: demonstration, display, farmer to farmer, on-farm/ranch research
- Farm Business Management: budgets/cost and returns
- Natural Resources/Environment: habitat enhancement
- Pest Management: physical control
The Great Eastern Shellfish Company farm raises premium quality salt oysters from spat to market size on Maryland’s Eastern Shore. We raise and harvest up to 250,000 quality salt oysters every 1-2 years, through modern float off-bottom aquaculture. Currently our oysters are raised in off-the-bottom floats consisting of flat mesh bags on rectangular PVC floats. It seemed to be the state of the art for off bottom culturing of oysters for the half shell market. It does well, but there is a problem. The oyster floats we currently use produce excessive fouling, are wasteful, and are cumbersome to harvest. Fouling is labor and time intensive to remove, prohibits oyster growth, and reduces water quality. We have analyzed or tried every system out there. After having made many improvements to our floats over the years, we now envision a new float that combines the best features of the best containment systems in use. It’s called a “Big Flip Float”. It’s for commercial oyster farmers. It grows oysters off the bottom. It is easy to load, easy to keep clean and easy to harvest from. With a SARE grant, we intend to implement the new Big Flip Float (BFF) containment system, and compare the performance of the new system against current practices. The measured benefits of the BFF system, in comparison with the numerous systems currently in use, will be shared with other growers, looking for the best method for raising oysters. We hope the BFF system will be found among the best for commercial oyster production.
Project objectives from proposal:
With the new BFF containment system, we intend reduce or eliminate fouling and reduce wasted resources. As a result, this improved system should enhance oyster growth, require less labor, produce less waste and environmental pollution, reduce costs, and improve water quality. With a SARE grant we hope to conduct a field trial of the new BFF system, in comparison with our current flat bag float system. This project will measure the performance of the Big Flip Floats with respect to the expectations listed above. Differences in the performance of the two systems (such as cost of repairing damaged bags, and improving water quality) will only be observable if each is implemented at a commercial level. Hence, we will need to deploy enough floats to contain about 100,000 oysters in each of the two systems. Results will be measured in a test area (with big flip floats) and a control area (with flat floats), over the course of one growing season, from September to March of the following year.
Performance of each system will be measured with respect to the following objectives:
1. Enhance oyster production, by allowing good water flow within the bags. Improving off bottom growing conditions may speed growth. If a higher percentage of oysters achieve market size on time, we can get more to market and have fewer to put back for another growing season.
Measure: percentage of oysters at or above market size at the end of the growing season
Measure: size distribution of market size oysters
2. Reduce labor, by reducing or eliminating biomass fouling, and hence the need for constant brushing and scraping of the bags and floats. The following measures will be reported per 100,000 oysters.
Measure: time to prepare and load flat floats vs. BFFs with oysters ready to deploy
Measure: time spent cleaning bags and floats
Measure: time to repair damaged bags or floats while in the water
Measure: time to handle and store fouled bags during harvest season
Measure: time to harvest and process oysters for market
Measure: time to clean and store emptied floats
3. Reduce costs and waste by reducing the disposal of cable ties and damaged bags.
Measure: Material costs for raising100,000 oysters in each system, including bags, cable ties (large and small), PVC floats, and replacement bags
Measure: Number of cable ties and bags disposed of (and equivalent cost)
4. Improve our water quality, by slowing or ending the release of biomass into the water.
Measure: Turbidity and dissolved oxygen content of water column will be monitored biweekly, with turbidity samples taken at the location of the floats before, during, and after fouling removal (for the control area) or float flipping (for the test area). Photos and videos will also be made to compare the effect of BFF flipping versus bag brushing.
All measures will be recorded over the course of the project. Time and expenses will be documented as they occur, in a log. Water quality data will be recorded biweekly for each system. At the end of the project, materials and labor will be totaled. Oyster size distribution at harvest will be measured. Water quality differences will be trended and averaged. All measures listed above will be compared for each system to look for significant differences in the outcomes.