Source: OYSTER SEED HOLDINGS, INC. submitted to
A NOVEL APPROACH TO INCREASING AND STABILIZING BIVALVE SHELLFISH SEED SUPPLY: THE MOBILE HATCHERY.
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
SMALL BUSINESS GRANT
Reporting Frequency
Annual
Accession No.
1016220
Grant No.
2018-33610-28317
Cumulative Award Amt.
$41,107.00
Proposal No.
2018-00395
Multistate No.
(N/A)
Project Start Date
Jul 1, 2018
Project End Date
Jul 31, 2019
Grant Year
2018
Program Code
[8.7]- Aquaculture
Project Director
Congrove, M.
Recipient Organization
OYSTER SEED HOLDINGS, INC.
425 CALLIS WHARF RD
GRIMSTEAD,VA 23064
Performing Department
(N/A)
Non Technical Summary
Shellfish aquaculture is a rapidly expanding agricultural industry in the United States, with landings more than doubling in the last 5 years and creating many new jobs. Culture techniques and the water-filtering nature of oysters make them a very low impact crop with arguably, a net benefit to the environment (a unique trait compared to other intensively farmed proteins). Comprised of salt and brackish in-water farms, shellfish farms raise animals born from hatcheries and ultimately sold to market. Shellfish hatcheries represent the tip of the pyramid in this industry where a large and diverse shellfish production market (thousands of companies) is serviced by a comparative handful of hatcheries (tens of companies). These hatcheries are relatively expensive and sophisticated operations requiring significant water handling and filtration equipment, large capacity for growing micro-algae feed, and other various life-support systems to hold, propagate, and grow juvenile oysters, but have notoriously inconsistent production for a variety of reasons including a delicate larval husbandry phase, harmful algal blooms, upland runoff, pathogenic bacterial species, acidified water, and more. This scenario of large scale hatchery production in relatively few places is precarious, the failure of just one of these facilities reducing seed supply to the industry. This project offers an alternative to the current status quo in U.S. shellfishhatchery production with the continued development of a highly efficient prototype mobile hatchery capable of moderate scale seed production fitted inside a 53 foot tractor trailer. Integral to producing seed in this hatchery will be the use of a novel setting system necessary to metamorphose oyster larvae into juveniles or seed. This project will evaluate this new setting methodology by comparing it with more traditional setting techniques. Should it prove to be effective, the facility will be evaluated overall in its ability to consistently produce oyster seed at moderate scale. With multiples of such a facility, hatchery production could become more decentralized effectively reducing seed supply shortages through redundancy while also allowing more participation in the seed market, increasing diversity.
Animal Health Component
100%
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
30737231060100%
Knowledge Area
307 - Animal Management Systems;

Subject Of Investigation
3723 - Oysters;

Field Of Science
1060 - Biology (whole systems);
Goals / Objectives
This project seeks to further a prototype hatchery developed by Oyster Seed Holdings, Inc (OSH) thathas served as the genesis for a novel concept: numerous moderately scaled, inexpensive, identical, mobile shellfish hatcheries operating simultaneously to realize, redundant, diverse, consistent, and cumulatively - large scale production of shellfish seed.The main goal of Phase I work is to completethe oyster larval cycle by successfully adding high density seed setting capabilities to the OSH prototype hatchery utilizing a novel system. Success ofthis goal will result inmoderate scale production of post-metamorphic oyster seed in this facility andwill ultimately allow for evaluation of the larger concept in Phase II: large scale, de-centralized, and consistent hatchery production realized by multiple moderate scale, mobile hatcheries.The objectives necessary to realize this goal arethreefold: (1) expand the ability of the OSH mobile prototype hatchery, currently capable of only pediveliger larvae production, to include post-metamorphic juvenile production; (2) evaluate a novel space-saving setting system to transition pediveliger larvae through metamorphosis using hard surface settlement and (3) evaluate the ability of the OSH prototype hatchery to produce, at moderate commercial scale, post-metamorphic seed oysters.
Project Methods
Traditional setting techniques of seed oysters consists of introducing competent(ready-to-set) pediveliger larvae to finely ground oyster shell (300-500 microns inlength) in large water volume systems called "downwellers" which contain thisground oyster shell on bottom-screened cylinders ("silos") where confined pediveligerlarvae are encouraged to settle and metamorphose as algae feed and seawater flowdown through the ground oyster shell and settling larvae. In a traditionaldownweller setting system (TDS) a trough delivers water and algae feed to siloscontaining the ground oyster shell and larvae before flowing out of a stand pipe thatmaintains the water level in the tank. Important to note here is the large footprint andwater volume required for this type of setting, approximately 0.5 square meters per 1million larvae.The setting system to be evaluated consists of utilizing hard surface substrate towhich competent pediveliger larvae will attach briefly before subsequent removal andtransfer to a post-metamorphic growth system comprised of fluidized seed bottles. Thesystem will consist of two 200L tanks approximately 50cm in diameter and 90cm tall,each containing nine pvc plates approximately 45cm square and 5mm thick. Thebottom pvc plate will rest approximately 7cm off the bottom of the tank with eachsubsequent plate approximately 7cm above the previous. Water andalgae feed will constantly flow into the setting tank proportionally to maintain a feeddensity of approximately 100,000 cells ml-1. Water exiting the tank will pass through a"banjo" screen to retain larvae within the setting tank.A new larvae culture will be started in the hatchery each week as conditionsallow. This should allow for setting of larvae approximately at one week intervals. Thefirst 8 larvae cultures that provide competent pedivelgier larvae will be used tocomparatively assess performance of the HSS vs TDS. For each larvae culture the first5M competent pedivelgers to come out of larvae culture will be pooled, then separatedinto one group of 1 million and one group of 4 million.The group of 4 million larvae will be placed into HSS and allowed to settle for 2days after which the tank will be drained completely, retaining any un-set larvae. Thepvc plates will be scraped using a razor blade removing all oysters attached to theplates. Live oysters will be estimated under a microscope using volumetric subsamplingtechniques. A settlement rate will be calculated by dividing the estimated livecount of oysters scraped from the plate (O) by the number of larvae added to the settingtank (L).Settlement Rate = O/LThe HSS tank will then be refilled and the retained larvae from drain-down will be addedback to the tank and allowed to settle over another two day period after which the tankwill be drained again, larvae retained, and plates scraped on consecutive day 4.Remaining larvae will be re-set one more time, with the last plate-scraping occurring onconsecutive day 6.The group of 1 million will be placed into a TDS system and allowed to settle for6 days with tank drain-downs every two days. By nature of the system larvae will beretained inside the setting silos and allowed to continue settlement when the tank is refilled. Settlement rate will be estimated as above with microscope aided volumetric subsample counts on day 6.TDS settlement rates at day 6 and HSS settlement rates at day 2, 4, 6, andaverage for each set cohort will be reported. Setting performance of HSS vs TDS willbe assessed using these settlement rate data.To assess survival and growth of post-set seed, set oysters from HSS on day 2,4, and 6 will be pooled and added; and set oysters from TDS on day 6 will be added toseparate post-set "fluidizer" bottles to assess growth and post-set survival. Oysters willbe added at similar densities (volume of seed per bottle) as not to effect growth.Estimated counts from the settlement rate calculation (O) as well as the total initialvolume (V) added to each bottle will be recorded. Count will be estimated and volumerecorded again after one week (interval1) and again after two weeks (interval 2).Growth will be measured as an increase in measured volume. Survival will bemeasured as percent still alive.Growth = V1-V0 (interval 1), V2-V1 (interval 2), V2-V0 (cumulative)Survival = O1/O0 (interval 1), O2/O1 (interval 2), O2/O0 (cumulative)After eight setting trials assessing relative performance of HSS vs TDS in termsof settlement rate, post-metamorphic growth, and post-metamorphic survival; andassuming satisfactory performance of HSS - subsequent larvae production will goexclusively into HSS in an effort to maximize seed production from the hatchery.To realize the potential of this concept of multiple, de-centralized, mobilehatcheries there is a critical minimum level of production necessary for economicfeasibility. This production is estimated to be approximately 15M seed per year perfacility and the remaining time in the season after the HSS evaluation will be used todemonstrate the ability of the prototype facility to produce on pace to meet that level ofproduction.

Progress 07/01/18 to 07/31/19

Outputs
Target Audience:Established hatchery operators can benefit from both primary efforts of this proposal including the novel setting system and the mobile hatchery concept. Hatchery operators are always looking to increase efficiency and reduce risk, and this project offers opportunities to this audience in both these categories. Prospective hatchery operators stand to gain the same benefits from the technology proposed in this project, but are also presented with some unique advantages. One such advantage is that the mobile hatchery concept is the perfect platform for vetting prospective permanent hatchery locations. It is also a much more economical way to start a hatchery program rather than building a brick and mortar facility with its significantly higher capital costs. Some prospective operators, particularly in less developed parts of the world, can have trouble sourcing all the equipment and components necessary to set up a modern hatchery. With the mobile hatchery, this "hatchery-in-a-box" concept can provide a sophisticated hatchery shipped and delivered to a site that may otherwise have difficulty building one from scratch. Other audiences that may have interest in this project include the shellfish research community. While much smaller than that of commercial operators, research outfits have their own needs for production, not to mention that these mobile hatchery facilitates could be used for a level of replication (multiple identical hatcheries operating at various locations) that currently does not exist. Changes/Problems:While the critical question as to the viability of the HSS system was evaluated, albeit not with as many trials as originally designed, there were not sufficient larvae cultures to address goal 3 of the project: to evaluate the commercial production potential of the prototype hatchery utilizing the HSS system. The reason for this significant change to the project scope was significantly depressed, and persistent low salinity at the current prototype hatchery site, as well as at all alternative site options. Early 2019 presented salinities below 10ppt at all sites available for operation of the hatchery. With a small and compact hatchery relying on single pass flow through systems to meets its production needs, successful operation in these low salinities was impossible. Other water quality parameters were surely affected as well, as the low salinity event was a result of extremely high and abnormal rainfall totals in the Chesapeake watershed causing significantly high streamflow at measured fresh water inputs to the Bay. Note in Figure 1 the significantly increased stream flow data for the Susquehanna River at the Coniwingo Dam as well as the significantly depressed salinity during the same time period for a Chesapeake Bay National Estuarine Research Reserve monitoring site adjacent to the hatchery location. The Susquehanna River contributes approximately 42% of the freshwater to Chesapeake Bay. This extremely high river flow at this and other Chesapeake Bay tributaries led to exceptionally low salinity conditions that began in late 2018 and persisted until the summer of 2019. As salinity finally began to increase in late summer, the hatchery was able to successfully culture larvae again, despite ongoing challenging conditions due to sub-par water quality limiting larval culture survival. This allowed for the the three trials in late July and August of 2019. Figure 1: Top Panel: Streamflow data for the Susquehanna River at the Coniwingo Dam. The historic mean is in blue. Actual readings May 2018 - March 2019 in green. Bottom Panel: Salinity data for a monitoring site adjacent to the hatchery. Historic salinity mean in blue. Actual readings May 2018 - March 2019 in green. ? What opportunities for training and professional development has the project provided?The project has provided the opportunity for professional development of the technician funded to carry out these trials. This technician is now proficient in HSS operation and can be employed to further its development or implement it in other hatcheries. How have the results been disseminated to communities of interest?This technology is proprietary and has therefore not yet been disseminated to communities of interest. Furthermore the technology is still in the R&D phase. Once deemed sufficiently proven, the results will be disseminated as part of a commercialization plan to provide the technology to interested parties either for sale or license. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? The necessary modifications were made to expand the OSH mobile prototype hatchery to include a novel setting system in the facility therefore closing oyster seed production cycle within this facility. The completion of this work was followed by the evaluation of the novel setting system. This hard surface setting system (HSS) reduces the water and feed requirements of a traditional downwell setting (TDS) system by more than half and reduce physical space required for the system to just 20% of traditional. Challenging water quality conditions represented by persistent low salinity in most of Chesapeake Bay in 2019 presented difficult larvae culture during the project period, which limited trials from the proposed 8 to 3. These three larvae cultures however, were sufficiently successful to accomplish, in part, the goals set out in this project. Primary in these efforts was to evaluate a novel, space-saving setting system to transition pediveliger larvae through metamorphosis using hard surface settlement techniques. Three distinct setting trails were completed in the mobile hatchery in July and August of 2019 comparing the HSS method of setting to the TDS method of setting. Trials consisted of placing ready to set, pediveliger larvae from the same cohort and harvest grade in the HSS system and in TDS, enumerating resulting juvenile oysters for each and calculating a setting rate. In each of the three trials the HSS method outperformed traditional downwell methods as displayed in table 1. TDS HSS Trial 1 11% 31% Trial 2 11% 20% Trial 3 21% 32% Table 1: mean setting rate for TDS and HSS setting rate. Setting rate is calculated as the number of recovered post-set seed divided by the number of larvae set. While these initial results are promising more trials are necessary to confirm that the HSS method is consistently converts more larvae to seed than TDS as suggested by these limited trials. Nonetheless, this represents a promising, and highly efficient new technique to transitioning oyster larvae through metamorphosis. Unfortunately, due to the extremely compressed larvae production season in 2019, a function of the significantly and persistently depressed salinity levels in Chesapeake Bay, the project was unable to transition to the third goal of the proposal which was to evaluate the ability of the prototype hatchery to produce at moderate commercial scale, post-metamorphic seed oysters. It can however be assumed that with the successful implementation of the HSS system, under adequate water quality conditions for successful larvae culture, the prototype hatchery could successfully produce commercially significant amounts of oyster seed.

Publications


    Progress 07/01/18 to 06/30/19

    Outputs
    Target Audience:System design and instillation was sompleted during this period, work to start in early July. Changes/Problems:The only major changes to the project have been in terms of schedule. Multiple setbacks and environmental issues have caused lengthy delays. The Chesapeaek Bay watershed recieved record breaking rainfall in the Fall and winter of 2018 and spring of 2019. This rainfall was sufficient to reducethe salinity in the Bay by half and severely hamper shellfish larvae production at locations where salinity is marginal. This was the case of the Oyster Seed Holding main hathcery which was also the original site for the protytpe to operate this season. Much time was lost as focus of the PI changed to getting the main faciltiy abck up and running. The original technician that was going to operate the protype hathcery took another postion and so there was also time lost in trying to find a replacement. In the meantime the protype was moved to a more sutiable location where salinity was higher and started up. Originally spawning was to commence in February. Due to the low salinity,need to move the prototype hathcery,time spent on the main hathcery, and a the lack of a technician, the first culture at the nw location did not start until mid April. Multiple equipment failures during that culture required it to be abandoned and the nesessary repairs made. Those have been made, a new technician has been hired, and spawning is now happening weekly The first group of larve will go into setitng in July. What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals?Multiple larvae groups will be spawned and reared in the hathcery and set in the novel setting system and in a traditional system. Setting rates of the two systems will be caclulated to assess the relative performacne of the two systems

    Impacts
    What was accomplished under these goals? Objective 1 is complete. The prototype hathcery has been succesfully modified to house all systems necessary to rear larvae, set larvae, and rear early seed. Next the novel setting system will be evaluated.

    Publications