The NZ Green Lipped Mussel (Perna canaliculus), also known as the NZ Mussel, Green Shell Mussel, Kuku, and Kutai, is a bivalve mollusc in the family Mytilidae. Bivalve molluscs are recognised by their external covering that is a two-part hinged shell and the soft-bodied invertebrate inside.
Shells can be up to 260mm long, 110mm wide and 90mm deep, with bright green shells in juveniles, while wild adults are often dark purple to black; farmed adults green to yellow-brown. All NZ Green Lipped Mussels possess a distinctive green lip along the inside margin of shell, hence the name. These mussels are only found in NZ waters, and have been sustainably farmed for commercial purposes since the 1970s in the clear unpolluted waters of NZ.
Benefits of using NZ Green Lipped Mussels
NZ Green Lipped Mussels are the only species of mussel to contain a bioactive protein that acts as anti-inflammatory and helps repair muscle and increase joint function. This is why you’ll find 3% of NZ Green Lipped Mussel in all of Ziwi’s air-dried and canned recipes. These delicacies are also a great source of iron, protein and omega-3, and the fresh meat is plump and sweet.
Sustainability and environmental practices
Green Lipped Mussels are NZ’s most iconic seafood, and are rated by the Monterey Bay Seafood Watch Programme as one of the most sustainable seafood products in the world.
NZ Green Lipped Mussels are found in four main areas in NZ: Marlborough, Golden Bay/Tasman Bay, Coromandel and Stewart Island. They grow on longline technology that uses continuous crop ropes, ranging from 3,000 to 4,200 metres in length. The time from spat to harvest varies by growing area and ranges from 26 months in the Coromandel to 48 months in Stewart Island (colder temperatures slow growth). The oceans in NZ provide perfect growing conditions and are not hindered by overpopulation, pollution, or heavy sea traffic which can damage or kill crops.
Perhaps the most positive aspect of this type of farming in the environmental sense is the fact that no harmful additives are used. The only artificial or man-made components are the inert floats, ropes and anchors that provide a support for the mussels while they grow. There is no use whatsoever of fertilisers, herbicides or pesticides; in that respect mussel farming is even cleaner and greener than organic gardening.
Living with NZ Green Lipped Mussels
While the mussels are growing in NZ’s blue pristine oceans they also have another job! Known as the ecosystem engineers of the ocean, a valuable function performed by mussels is the ability to capture, clean, and process organic matter that contain bacteria and fungi from water columns. Mussels do this by extracting the nutrients and depositing remaining organic material for other marine life to consume. One mussel can filter six litres of water per hour!
Mussels also provide a safe, strong shell for larvae and algae to attach to, so when mussels are present in large numbers, they can become underwater gardens that in turn attract fish to feed. Because mussels firmly anchor themselves to the crop ropes, they also act to stabilize the ocean currents, thus minimizing the effects of floods and wave action.