Nepedia
Back to Discover
Advanced Reader
📖

Mariculture

language culture Maturity 11-13 Next article →

Mariculture is a specialized branch of aquaculture focused on the cultivation of marine organisms within seawater. This practice involves raising various species for food, animal products, and industrial uses. It is a vital part of global food production and resource management. Mariculture can produce high-value items like cultured pearls for jewelry and cosmetics. It also provides raw materials such as fish meal, nutrient agar, and even bioplastics. By farming in the ocean, humans can harvest resources in a way that mimics natural ecosystems.

Færøsk havbrug.1
Færøsk havbrug.1

The mechanism of mariculture depends on the specific environment used for cultivation. In onshore mariculture, farmers use manmade tanks, ponds, or raceways. These structures are supplied with seawater rather than fresh water. A key feature is that the water column provides the necessary nutrients. This reduces the need for artificial feeding and preserves the natural diet of the species. Inshore mariculture takes place in littoral waters or estuarine environments like bays and brackish rivers. Here, the tides help move and refresh the water. Farmers use tools like artificial reefs, nets, or long-line arrays of floating cages moored to the seabed.

MH Lochailort
MH Lochailort

There are three distinct types of mariculture based on their location. Onshore mariculture is often used for farming algae, such as plankton and seaweed, as well as shellfish like shrimp and oysters. Inshore mariculture focuses on species in tidal zones, using pens or cages. Open ocean aquaculture, or OOA, is a newer and more complex approach. It involves raising organisms in exposed, high-energy environments far from the coast. OOA uses cages or long-line arrays that are either moored or towed. This method has the potential to combine with offshore energy systems, such as wind farms, to use ocean space more effectively.

Microalgae cultivation facility along the Kona Coast of the Big Island of Hawai’i
Microalgae cultivation facility along the Kona Coast of the Big Island of Hawai’i

History shows that marine farming is both an ancient and a modern science. The Māori people of New Zealand have long-held traditions of farming shellfish. This includes the practice of *ahumoana tawhito*, or ancient aquaculture, where species like the toheroa were translocated. Modern mariculture has expanded rapidly over the last twenty years. This growth is driven by new technology and better formulated feeds. Improved biological understanding and better water quality in closed systems have also helped. Today, commercial open ocean facilities are active in many nations, including Chile, China, Norway, and Japan.

Færøsk havbrug.1
Færøsk havbrug.1

The scale of these operations is significant and global. In the United States, commercial facilities have operated in Hawaiian and Puerto Rican waters. The largest deep-water open ocean farm in the world is located 12 km off the northern coast of Panama. This specific facility focuses on raising cobia in highly exposed sites. In the realm of algae, researchers are exploring "marine permaculture." This concept uses artificial upwelling and submerged platforms to replicate natural seaweed ecosystems. If seaweeds sink below a depth of one kilometer, they may help sequester atmospheric carbon.

Microalgae cultivation facility along the Kona Coast of the Big Island of Hawai’i
Microalgae cultivation facility along the Kona Coast of the Big Island of Hawai’i

Different species require different management techniques within these systems. Shellfish farming is often a self-supporting system. Species like mussels, clams, and abalone do not require added feed, fertilizers, or antibiotics. They can even be used in integrated multi-species cultivation to utilize waste from other organisms. Finfish, such as salmon and cod, are managed differently. In intensive systems, farmers often use manufactured, nutritionally complete pelleted feed. This is sometimes delivered by automated computer-controlled systems to ensure efficient growth.

MH Lochailort
MH Lochailort

Despite its benefits, mariculture faces environmental and social challenges. One concern is the accumulation of waste from cage cultures. If fish are overfed, excess food can settle on the seafloor and smother invertebrates. Another major issue is the escape of farmed animals into the wild. For example, in December 1999, a storm caused 5,000 Siberian sturgeon to escape into the Gironde Estuary in France. Such escapes can lead to genetic pollution or the introduction of invasive species. To manage these risks, farmers must carefully select sites based on water depth, current speeds, and storm shelter.

MH Lochailort
MH Lochailort
649 words

Where will your curiosity go next?

Keep exploring at your chosen reading level.

🖼️ Images & Media (3)
File:Færøsk havbrug.1.jpg
Færøsk havbrug.1.jpg
File:Microalgae cultivation facility along the Kona Coast of the Big Island of Hawai’i.jpg
Microalgae cultivation facility along the...
File:MH Lochailort.jpg
MH Lochailort.jpg
More to explore

🔬 Go deeper

More advanced topics to explore

🪜 Step back

Simpler topics to build understanding

What is Nepedia?

A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.