California Sea Grant College Program

For nearly 90 years the shellfish mariculture industry in Humboldt Bay has coexisted with various stakeholder groups and the Bay’s delicate ecology. Presently, the shellfish mariculture industry in Humboldt Bay is composed of six shellfish producing businesses ranging in operational size from small-scale to large-scale. Commercial shellfish production from Humboldt Bay yields over 70 percent of California’s mature, market-sized, Pacific oysters (Crassostrea gigas) and Kumamoto oysters (C. sikamea). Shellfish growers in the Bay also produce seed from Pacific oysters, Kumamoto oysters, and Manila clams (Tapes semidecussata).

As the mariculture industry in Humboldt Bay is poised to expand its footprint, very limited data about the industry have been made available for planners and decision makers. The purposes of this thesis were to: (1) Gather reliable socioeconomic data about

the state of the mariculture industry in Humboldt Bay. (2) Evaluate the industry’s

strengths and vulnerabilities. (3) Assess the priorities for the industry moving forward.

(4) Provide an objective, accurate picture of the mariculture industry in the Bay for the purpose of clarifying how the mariculture industry operates and showing the industry’s economic contribution to the region. To achieve these goals, I used a mixed-methods approach consisting of semi-structured interviews with mariculture participants and other Bay stakeholders, a socioeconomic survey of mariculture businesses, document analysis, participant observation, and public workshops. Analysis of collected data showed that the mariculture industry in Humboldt Bay has many strengths. In 2016, the mariculture industry employed 101 people. These participants harvested over 9.5 million mature oysters and brought in $9.8 million in revenue. In addition to the mariculture industry’s strengths, mariculture participants were met with specific challenges that represent vulnerability for the future resilience of the industry. Challenges or vulnerabilities expressed by the mariculture participants included: obtaining permits, procuring seed, and the opposition from non-mariculture community members regarding expansion in Humboldt Bay.

Seed production is an important and growing part of the mariculture industry in Humboldt Bay and an area for future development. The burden of permitting and the conflict between stakeholders of Humboldt Bay should be addressed in order to expand the industry’s grow out grounds. In addition, it would also benefit the mariculture participants to work to address concerns from the environmental and scientific community about the impacts of oyster cultivation on the environment -- particularly eelgrass. Until concerns about eelgrass are studied and addressed in proposals for mariculture operations, permitting and expansion may continue to be challenges for the industry. Overall, the Humboldt Bay mariculture industry has many strengths andimprovements in some areas can increase the resilience and sustainability of the industry

over time.