Baltic Sea

Partner

Kerteminde Seafarm (KERTE)

Country

Denmark

Characteristics

  • Sea surface at 2-20ºC
  • Salinity of 8-20 PSU
  • Moderate light penetration
  • Lower nutrient concentrations compared to #1-3
  • Sheltered bays with limited exchange

Overview

At the Baltic Sea site, KERTE operates a 19-hectare marine facility in Kerteminde Bay. Located 4 km from the harbor at a depth of 8–12 meters, this demonstration site highlights an advanced, organic-certified Integrated Multi-Trophic Aquaculture (IMTA) model. The project utilises low-trophic co-cultivation strategies to maximise species value while keeping local environmental impacts minimal.

Infrastructure and technical innovations

The facility combines high-capacity outdoor growing frameworks with local academic laboratory support:

  • Deploys a scalable prototype consisting of 6 horizontal growout (H-RIG) units adapted to the regional oceanographic conditions. Each system features two 220-meter mainlines of 18mm PP-rope stretched with 15-meter growth lines spaced 1.0–1.3 meters apart, secured by screw anchors driven 1–2 meters into the seabed.
  • Seaweed polycultures are co-cultivated directly alongside low-trophic shellfish operations utilising specialised NZ Flip Farm and long-line systems.
  • Implements a high-efficiency automated direct seeding process with a capacity of 1,000 meters per hour. Utilizing a specialised binder glue and an encoder to control precise dosage onto 12mm rope, this system ensures equal light exposure and controlled growth conditions. This strategy supports multi-year harvesting on the same line for 4–5 years while heavily reducing operational sea-day requirements.
  • Integrates a dedicated hatchery and laboratory space at the Southern Denmark University (SDU), complemented by harbor facilities featuring cold storage, freezer systems, and space for processing and drying.

Cultivated species and production goals

The site executes strict, organic certification-based procedures, avoiding chemical treatments or antibiotics and operating under low stocking densities, to optimise the premium value of both macroalgae and bivalves:

  • Saccharina latissima: Cultivated via automated horizontal lines to reach a target yield of up to 30.0 t FW/y.
  • Palmaria palmata: Integrated within the horizontal arrays targeting a production capacity of 15.0 t FW/y.
  • Ulva fenestrata: Cultivated alongside the core crops with an expected target yield of 5.0 t FW/y.
  • Mytilus edulis: Co-cultivated on long-line arrays to yield an increased capacity of 125.0 t/y.
  • Ostrea edulis: Co-cultivated in specialized containment units targeting a production increment of 50.0 t/y.