Co-Culture of Green Sea Urchins and American Oysters

Project Overview

Project Type: Farmer
Funds awarded in 2024: $27,000.00
Projected End Date: 07/31/2025
Grant Recipient: Cranberry Oysters
Region: Northeast
State: Maine
Project Leader:
Lauren Gray
Cranberry Oysters


  • Animals: shellfish, other


  • Animal Production: aquaculture
  • Education and Training: on-farm/ranch research

    Proposal summary:

    I would be investigating the success of rearing American oysters
    and green sea urchins. Farming multiple species together with
    complementary ecological requirements is interesting both for its
    role in producing secondary products for market and creating more
    resilient multi-species farms but also for the potential of
    biofouling mitigation on shellfish grow out gear. I am uniquely
    situated to investigate the question of oyster/urchin co-culture
    success because I have been growing oysters since 2016 and
    regularly observe wild urchin populations on my offshore island
    site. Initial feasibility trials in farming green sea urchins
    on-site with guidance from Dr. Coleen Suckling from the Center
    for Cooperative Aquaculture Research proved successful. This
    project could be a powerful example for shellfish growers to
    increase farming efficiency, exploring the benefits of a
    symbiotic multi-species farm, as well as create a secondary
    market for oyster farmers interested in urchin culture.

    Project objectives from proposal:

    The objective of the project is to measure the success of rearing
    oysters and urchins together -- will farming urchins and oysters
    together result in better survivorship within either or both
    species? Are they particularly effected by environmental
    fluctuations in temperature or salinity? Which type of grow out
    gear, bottom or surface, is most user-friendly for the farmer to
    grow urchins and oysters together? Does either type of grow out
    equipment result in better survival and/or growth? Are urchins
    able to reduce biofouling on either type of grow out gear or on
    oyster shells and if so, is there a noticeable effect on oyster
    growth or measurable reduction in farming effort? Another key
    part of the study is to see if urchins and oysters can survive
    the annual overwintering/hibernation process that begins for
    oysters in November and ends in April. 

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.