Determining the Productivity Benefits of Two Novel Kelp Farming Systems

Project Overview

FW23-415
Project Type: Farmer/Rancher
Funds awarded in 2023: $24,868.00
Projected End Date: 08/31/2025
Host Institution Award ID: G251-23-W9210
Grant Recipient: Noble Ocean Farms
Region: Western
State: Alaska
Principal Investigator:
Melissa Skye Steritz
Noble Ocean Farms

Commodities

  • Vegetables: other

Practices

  • Animal Production: aquaculture
  • Education and Training: demonstration, farmer to farmer, networking, on-farm/ranch research, workshop, youth education
  • Farm Business Management: apprentice/intern training, community-supported agriculture, farm-to-institution, farm-to-restaurant
  • Natural Resources/Environment: biodiversity, carbon sequestration, habitat enhancement
  • Sustainable Communities: community development, community planning, community services, leadership development, local and regional food systems, new business opportunities, partnerships, public participation, quality of life, social capital, social networks, sustainability measures, values-based supply chains

    Proposal summary:

    Kelp farming is a relatively new method of food production in Alaska, with the first commercial harvest in 2017. Kelp farming in the U.S. began with the deployment of a submerged horizontal line (rope) seeded with spores that grow to harvestable size in six months. The conventional single-line approach takes up a lot of ocean space and tends to sag deeper than desired. Without wide spacing between these lines, tangling can occur, causing loss of crop or damage to the lines.

    In Prince William Sound, Noble Ocean Farm is one of three commercial farms growing kelp (seaweeds) for food.  During the first season, these farms struggled to keep the underwater array system (anchors, lines, buoys, connection points) tensioned during large tidal fluxes. We experienced equipment failures and lower crop density compared to kelp farms in other areas. This is a common issue for kelp farmers in Alaska, most of whom are struggling to achieve profitability. 

    As the seaweed farming industry expands, it is important to optimize kelp growth per foot of seeded line and per acre of farmed lease. Therefore, our research questions are: 1) How do we grow the most amount of kelp in the smallest footprint? And 2) What is the minimum amount of spacing allowable between lines?

    Recently, our Technical Advisor, Clifford Goudey, developed novel 5-line and catenary arrays. These allow close line spacing, powerful tensioning to prevent tangling, and numerous other advantages over present practices.

    We will conduct a side-by-side comparison of a conventional single-line array, a 5-line array, and a 25-line catenary.  Metrics will include: kelp growth per foot, ocean space used, costs, and array performance. This research will identify the most efficient configuration to inform current and future kelp farmers' design decisions. Results will be shared via a workshop, farm tour, and fact sheets.

     

    Project objectives from proposal:

    Research Objectives:

    1. Determine the efficiency of various kelp farm systems in producing kelp biomass.
    2. Characterize the pros and cons of kelp farming system options with respect to equipment, installation, monitoring, and labor costs vs. crop harvested.  
    3. Compare monthly growth, quality, and end-of-season biomass harvests per foot and per acre among  the farm systems tested.

    Education Objectives:

    1. Inform present and aspiring seaweed farmers about opportunities in kelp farming.
    2. Explain farm system options and their pros and cons using a hand-on educational workshop.
    3. Show three different array systems to current and aspiring farmers, including early career mariculturists from the local and nearby communities.
    4. Create fact sheets to disseminate our research findings to kelp farmers throughout the entire Western United States via email and social media networks. 
    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.