As a non-native species to Alaska, Pacific oyster growth begins in a shellfish hatchery, since natural reproduction does not occur in Alaskan waters. Most seeds are still imported from outside Alaska. However, outstanding ongoing efforts and fruitful collaborations between the industry and the scientific communities are paving the way for a commercial-scale supply of high-quality seed produced in Alaskan-based hatcheries.
When producing, harvesting, or buying spat to be introduced to the farm, seed quality is of profound importance, as it will significantly influence the quality of the final product. Three shellfish hatcheries are permitted to operate in the state: OceansAlaska, Katchemak Shellfish Mariculture Association (KSMA), and Alutiiq Pride Shellfish Hatchery (APSH). (one additional permit for NOAA Ted Stevens Marine Research Institute Hatchery in Juneau).
Consistent and efficient microalgae production is an indication of the hatchery's seed quality
Oyster spat.
Science, R&D, training, and business in one place
Case study OceansAlaskaSpecies: Pacific oyster, and permitted for 3 other shellfish species, 13 seaweed species, and red sea cucumber
This project includes educators, scientists, fishermen, and business leaders and aims to promote shellfish culture as an economic driver for Southeast Alaska. It is a non-profit venture dedicated to expanding mariculture and enhancing wild stock for oysters, geoducks, sea cucumbers, and kelp in Alaska by providing commercial quantities of seed. OceansAlaska aims to achieve self-sustainability by selling seeds to small US and Canadian growers.
Innovations & approach
High quality, well fed, 5-7 year old broodstock oysters
Water flow, temperature, lighting, and nutrient-feeding regimes are fully monitored and controlled for environmental condition optimization.
The first stage of tank growth involves downstream water flow to enhance seed settlement on ground oyster shells and small sand grains for 3-7 days. The flow then reverses to an upwelling flow to allow constant algae and oxygen availability to the seeds.
When bigger, seeds are moved into a bottle system with an upstream feed flow of water, oxygen, and algae, which creates a gentle mixing motion for even distribution and uniform growth.
Sterilizing and filtering fresh seawater down to 0.2 microns
Chunk Kelly, Nursey Technician & Maintenance Manager at OCeansAlaska floating facility in Ketchikan
We grow different algae species in various sizes to provide a variety of feeds so the oysters can eat a healthy meal. Some of these big diatoms are more like steak and potatoes, and other species are like a little vegan salad. We mix them all and pump them into the tanks so they can choose from a variety of foods.
Notable points
- Permitted to culture 4 shellfish species, 13 seaweed species, and red sea cucumber.
- Growing a selection of warm water and high-quality microalgae species to supply oysters with a mix of versatile, nourishing, and different sizes of feeds and nutrients.
- Working closely with industry players and academia to build a local commercial-scale Pacific oyster seed supply and provide workforce training to further enhance a resilient, self-sustaining Alaskan oyster industry.
Pacific oyster hatchery under a non-profit organization at Homer Spit
Case study Kachemak Shellfish Mariculture AssociationSpecies: Pacific oyster
Capacity: 5 million oysters per year
Founded in 1994, KSMA emerged as a response to the challenges faced by oyster farmers in Kachemak Bay in its early days. It is dedicated to promoting shellfish mariculture practices and educating and collaborating with marine science programs to enhance the health of coastal waters. In 2009, KSMA decided to build a Pacific oyster hatchery to supply a local source of quality seed.
Innovations & approach
With the season starting in mid-December and ending in late May, the hatchery can provide around 5 million seeds that can be transferred to nurseries.
Strict algae count protocols are followed to maintain healthy cultures, reach optimal cell densities, and mix in the feeding tanks.
Growing three different species of algae, two diatoms, and a flagellate to provide a mix of algae to the juvenile oysters.
The exterior of the hatchery
Notable points
- The hatchery's focus on training and expertise, with a small dedicated team managing operations and feeding protocols, showcases a unique hands-on approach along with a scientific approach that has proven successful in producing optimal oyster seed sizes.
- Growing from larvae to 2-5 mm seeds in nearly a month and shipping them to FLUPSYs across the state.
- Mixing algae with seawater in specific ratios based on measured densities and maintaining optimal temperature and CO2 conditions for accelerating seed growth efficiently and effectively.
Joint Innovation projects
Design and comprehensive planning of an Alaskan optimized intermodal freight container based shellfish setting and pre-nursery seed boosting system
Addressing the challenge Alaskan oyster farmers face in accessing larger-sized oyster seeds is crucial for optimizing growth within the limited growing season due to cold water conditions. By focusing on delivering locally conditioned, large-sized oyster seed to instate nurseries at the right time, this project builds upon ongoing oyster hatchery work at OceansAlaska's facility in Saxman. Utilizing container-based pre-nurseries that cultivate micro-algae for feeding oyster seed and provide water filtration and heating, the project offers an innovative solution that can be tailored to various locations and organizational needs. Partnering with experienced entities, the project aims to enhance oyster farming practices in Alaska, with results shared through educational outreach programs and site evaluations.
Developing improved seed of the Pacific oyster for the Southeast Alaska regions
This project aims to enhance oyster farming in Alaska by addressing the challenge of slow growth and high mortality rates in oysters sourced from hatcheries optimized for lower-latitude conditions. The project will develop a selective breeding program targeting Alaska's environment through controlled genetic crosses and field assessments to improve oyster performance. Collaborating with NOAA Fisheries scientists, the project plans to create within-species hybrids at the Pacific Hybreed hatchery, transfer them for acclimation and data collection, and deploy them at the Little Port Walter Research Station for growth and survival evaluations. The project will introduce innovative tools for developing hybrid genetic lines tailored to cold-water ocean conditions.