Flathead grey mullet – Shrimp polyculture

Farmers can farm flathead grey mullet fish (Mugil cephalus Linnaeus, 1758) with black tiger prawn or whiteleg shrimp. Flathead grey mullet also has many other English name such as flathead mullet, striped mullet, black mullet, bully mullet, common mullet, grey mullet, sea mullet and mullet.

Flathead grey mullet has good vitality. The fish can grow and develop rapidly. Flathead grey mullet has many advantages for polyculture because it can live in environments with different ranges of salinity and heat. It can grow well in brackish water, salt water and fresh water.

As an omnivorous, flathead grey mullet can eat organic humus at the bottom of the pond, leftovers from shrimp, algae, or lab-lab. These feeds are harmful agents causing pollution and pathogens in shrimp-farming environment.

Flathead grey mullet polyculture helps balance the ecological system. It creates a favorable and safe environment for shrimp to grow and develop. Finally, this type of polyculture avoids epidemics or diseases causing damages in shrimp health. Actual experiments applying flathead grey mullet - shrimp polyculture show that water quality in ponds is improved significantly. Along with that, mortality rate of shrimp due to diseases is reduced, even in ponds with degraded water environment.

Combining black tiger prawn or whiteleg shrimp farming with flathead grey mullet is suitable with semi-intensive method. It is a new direction for shrimp farmers.

Shrimp farms intercropped with flathead grey mullet can conduct the following guidelines:

1/ Farming flathead grey mullet in shrimp ponds: After stocking shrimp for 1 month (shrimp can reach the weight of 3-5 grams/shrimp), farmers can stock flathead grey mullet (size 10-20 grams/fish) at a density of 10 square meters/fish.

2/ Rearing flathead grey mullet in settling ponds, then pumping water from settling ponds (where flathead grey mullet is farmed) to shrimp ponds. This method is suitable for cases when the sizes of flathead grey mullet and shrimp are not large enough to stock together.

3/ Raising tilapia in settling ponds, then pumping water from settling ponds (where tilapia is farmed) to shrimp ponds and combining with the stocking of flathead grey mullet to shrimp ponds.

4/ After harvesting shrimp, transfer flathead grey mullet from shrimp ponds to settling ponds and continue culturing as commercial fish.