Productivity of a seaweed farm is measured by the number of harvests a year and the biomass increase in weight (yield). Some seaweeds are harvested fully, meaning the entire biomass is removed from the site, while others are harvested partially, with some biomass remaining for further grow out. Yield is often stated in kilograms (kg) per metre (m) of line, since metric tonnes (MT) per hectare (ha) is not always a common measure among farmers.

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Eucheumatoids, due to their fast growth cycles, can be harvested many times a year, typically every 30-45 days.

The region and season help determine how many harvests are possible. Overall peak production in the Philippines is from March to May for example, which falls in the dry season. In a lot of regions in Indonesia, the South of the Philippines and Malaysia, farming takes place throughout the entire year. There are months with lower yields, however farmers generally continue farming activities. Producers often try to maximise  cycles of cottonii for as long as possible, but if conditions become too challenging, they switch over to spinosum.

Within about one month the weight of the seedlings can be multiplied between 3 to 5 times. The actual fresh weight yield per metre of line is the weight of the total harvest minus the initial weight of the seedlings. It can only be roughly calculated, since farmers rarely measure the fresh weight of the harvested seaweed nor the initial weight of seedlings deployed. However, the farmers usually estimate their yield increase based on the dry yield and the size of the seedlings times the number of seedlings per metre.

Although an average yield per hectare could be calculated based on the number and length of culture lines per hectare and the yield per metre of line, it would not be representative for Eucheumatoid farming.The amount and density of culture lines fluctuates a lot between different farms, regions and methods applied. 

Transportation of harvested biomass

The amount of labour needed for harvesting will depend on the operations, farming method and size of the boat. The size of the boat in turn depends on the operations and capital availability of the farmer. Boats are not always powered by an engine and some need to be paddled. In off-bottom cultivation the harvesting is usually done at low tide and smaller buckets of all types are used to collect the harvested seaweed from the lines or even entire lines. 

Explore another seaweed species:
Eucheumatoids  |  SaccharinaUndaria  |  PyropiaGracilaria

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