Monitoring giant kelp growth and environmental variability at an offshore aquaculture farm

Award Period
Award Amount
Agency Name
Ocean Rainforest, Inc
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PI First Name
PI Last Name
Area/s of Research
Climate Change Science
Ecology and Evolution
Natural Marine Resources

Ocean Rainforest, Inc. (ORI) is a commercial mariculture venture in Santa Barbara, CA. With support from the Advanced Research Projects Agency – Energy (ARPA-E), U.S. Department of Energy, the firm has developed an offshore kelp cultivation strategy that has the potential to support the sustainable expansion of mariculture in the United States. To test that strategy, ORI established a pilot project to develop a commercially viable seaweed production farm. The demonstration farm is located in the Santa Barbara Channel 1.1km offshore from Hendry’s Beach at the Santa Barbara Mariculture Company (SBMC) site leased from the State of California.

ORI is currently growing Macrocystis pyrifera, more commonly referred to as giant kelp. This form of kelp has been known to grow up to a foot and a half per day in ideal conditions. Giant kelp has many commercial applications including human-grade food, animal feed, cosmetics, medicine, agriculture, and biofuels. As part of this project, ORI has begun several experiments at both its onshore hatchery and at the SBMC site to optimize kelp growth and to develop a better understanding of the ecosystem impacts and benefits that farmed kelp has on the surrounding environment.

To date ORI’s studies have included regular monitoring of the kelp biomass and water column and sediment observations within and around the SBMC site. While not a formal part of its monitoring program, ORI has become aware of a noticeable increase in pelagic fish activity within and around the site since the first kelp crop was outplanted in March 2021. Anecdotally, there may be a beneficial relationship between the farmed giant kelp and fish communities in the area.  Systematic observation would develop a better understanding of this relationship and potential benefits to ORI’s program going forward. ORI, however, does not have the expertise or resources to perform the necessary studies to gain that understanding.

The purpose of the UCSB project in collaboration with ORI is to establish a baseline of fish abundance at the kelp farm and monitor changes in abundance and juvenile fish recruitment throughout the developmental life cycle of the kelp at the site. The UCSB project will supplement the ORI research program that includes monitoring kelp biomass, environmental parameters, and infrastructure conditions. Monitoring these three areas will remain ORI’s responsibility.

The objective of the UCSB project is to regularly conduct SCUBA surveys at the kelp farm to document temporal variability in the species composition, abundance, and size distribution of the fish community over the course of one year.