Surplus on Ostrea edulis spat – provision of larger quantities possible

Ostrea Production AB is happy to announce that there will be a large quantity of single spat for sale this year – about 15 mio. These are third generation broodstock from bonamia-free waters around the Koster island (Skagerrak), which is a marine reservation area. They are breed in a land-based hatchery. The spat is expected to be between 5mm to 7mm when ready for sale. But even bigger sizes will be available throughout the year. 

Ostrea Production AB currently holds a surplus on spats available throughout Europe.
Please contact Christian Vorbeck, managing director, for further information:
+46 73 151 6326 or via

Some background information on the hatchery:

Ostrea Production AB runs Sweden’s only oyster hatchery. The company has a dedicated track record and experience in breeding Ostrea Edulis on the northwestern island of Koster in the Skagerrak in the middle of Sweden’s only maritime resort.

The Skagerrak Sea doesn’t have any tide why the farming is done vertically, in stapled trays hanging from longlines. Each line is 200 m long and has 100 hanging tray staples. Ostrea has therefore developed a method where the harvest take place from a service boat equipped to automate the handling of oysters to streamline the harvest and reduce the need of personnel.

The breeding is done in a controlled environment, water quality and water temperature and light, securing a genetically healthy offspring. The water in the Skagerrak is bonamia free. 

The larvae are collected and placed in indoors water tanks where the environment also is controlled.

As in all forms of aquaculture the hatching of larvae is challenging, especially the metamorphosis from larvae to spat is crucial. This step has been successfully developed, made possible thanks to the team whose academic approach with a science-based methodology has paid off. All the different parameters have been identified and developed. A breakthrough was made in 2018 when the survival rate jumped from 2 percent to 40 percent and thanks to further improvements of the hatchery production technology the survival rate jumped again in 2019, to 81 percent and in 2023 up to 90%.

When the larvae settle, they are moved to new tanks for continued growth. They are fed with microalgae, produced within the hatchery for highest quality. When the spat has reached a size of 6 mm, it is ready to be moved to the sea.