Performing Department
(N/A)
Non Technical Summary
The green sea urchin (GSU), is an economically important emerging aquaculture species in the Northeastern US, it's edible gonad, is known as roe or uni.GSU aquaculture production by small to medium sized producers orientate their practices and timings around gonad development stages during growth. For example, GSUs are harvested for the market when the gonads are at early development stages of producing eggs, a time when they are large, brightly colored and firm, characteristics which are appealing for seafood consumers. However, when the animals can be reproduced to support aquaculture in a hatchery during later gonad development stages, they do not show these marketable characteristics making them unmarketable. Harvesting and aquaculture reproductive work at present follows traditional timings established from surveys conducted up to 40 years ago, but producers have recently reported potential earlier shifts of reproduction occurring and an overlap with the traditional harvesting period resulting in lost economic opportunities. To address this problem, this project will conduct regular sampling of GSUs to measure and confirm current ideal harvesting and reproductive timings. This will be compared against historical and traditional production timing to identify whether there are changes in the ideal harvesting and reproductive timings. It will also work towards identifying the causes of these shifts in timing (e.g. climate change) to help with future production practice decisions. This project will work with the regional industry to determine whether production practices and timing need to be updated and applied to help sustain the industry.
Animal Health Component
0%
Research Effort Categories
Basic
60%
Applied
40%
Developmental
0%
Goals / Objectives
The objectiveof this seed project is to determine whether the green sea urchin (Strongylocentrotus droebachiensis) reproductive period is shifting to an earlier phase, and therefore, requires changes in the management of production practices to expand and improve industrial sustainability within the Northeastern Unites States.
Project Methods
This project will conduct monthly sampling, for up to two years of green sea urchins (Strongylocentrotus droebachiensis;GSUs) from the commercially active central coastal region of the Gulf of Maine to determine how gonad function affects ideal harvest and reproduction timing.Marketable characteristics (e.g.gonad color, gonad index, reproductive stage(via histological sectioning), and tissue firmness) will be measured to elucidate during which months the GSUs exhibit desired marketable characteristics and therefore the ideal harvesting period, as well as providing some insights towards when the reproductive period occurs (Milestone 1).GSUs will also be collected broadly across the across the historically recognized and present day suspected reproductive period across two years to capture the full temporal reproductive season and reproductive viability. To assess this, this project will employ hatchery production methods. After inducing the GSUs to spawn,fecundity, and egg size for several females will be quantified and crossed with males to gain fertilization and hatching success (%) data. These methods will give a strong representation of the reproductive process and provides insights to their broodstock viability needed for a hatchery (Milestone 2).This field work will becoordinated with a detailed daily and interannual seawater parameter logging survey (e.g. temperature) at GSU sites and compared against public seawater parameter data archives derive from surface water buoy active services (e.g. NOAA) to determine whether these are suitable for explaining phenological changes in GSU gonad function and to represent GSU site urchin seawater parameters which can be used for future efforts (Milestone 3).Collectively, these present day GSU samples and seawater parameter data will be compared to open access historical data to determine whether phenological changes are occurring in gonad function (Milestones 4 and 5).Data analysis for this project will be largely exploratory to establish whether any patterns of changed timing for harvesting and hatchery production are occurring.There will be strong effort towards knowledge exchange and collaboration, through direct communications, meetings, presentations, and data sharing, with the GSU industry to determine whether changes in aquaculture management are required and can be experimentally applied and to coordinate larger scale funding capture effort to broaden these efforts (Milestone 6). We expect to see interannual variation of temperatures and gonad function but also expect to confirm an overall trend of phenological shifting to an earlier phase of the reproductive period and ideal harvesting periods.