Macrocystis pyrifera aquafarming: Production optimization of rope-seeded juvenile sporophytes

Highlight
- A hatchery protocol for kelp aquaculture at a commercial scale facility was developed.
- Compared to previous protocols the production time required to reach the seeding size and the protocol complexity was reduced.
- These improvements impact in two ways: economically, reducing labor, supplies, and energy costs, and shortening the hatchery phase.

The use of kelp in different human activities has increased over recent decades and this demand is increasing the demand for cost-effective farming technologies. In the case of the giant kelp (Macrocystis pyrifera) there is a large accumulation of knowledge concerning the relevant information required for aquafarming that allowed the installation of a 20 ha pilot culture farm 5 years ago in southern Chile. However, this experience indicated that to achieve a production level above 200 tons per hectare per year it is necessary to optimize all the protocols starting from the hatchery level through to the growing phase in order to be cost effective. In this study we present information on optimizing the hatchery phase of M. pyrifera culture. The results show that it is possible to obtain 4 to 5 mm long M. pyrifera juvenile sporophytes attached to seeded rope in less than 45 days. To obtain this result, temperature should be 12 °C with a photon irradiance of 12 μmol m− 2 s− 1 and a photoperiod of 16:8, L:D. In addition, macro and micronutrient concentrations should be maintained as the traditional Provasoli culture medium indicates, and with aeration of 414 L h− 1 to maintain water movement in the culture system.Statement of relevanceCommercially hatchery kelp farming protocol development is presented.