How do mussels grow?
  • A shellfish like a mussel grows the same way that all other living things grow. They turn the food that they eat into energy which makes their cells (the tiny building blocks that make up the mussel) divide and grow so that the shell that they live in and the mussel itself grows.
  • You’ll find mussels growing naturally on the rocky shoreline.
  • They use the bristly growth at the end of their shell to cling to things like rocks in the water.
  • Because so many people want to eat mussels these days companies have developed mussel farms where they grow millions of mussels on rows of ropes in the sea.
  • The Maori name for food that grows/lives in the sea is Kaimoana
  Did You Know?
  • Mussels start as eggs and female mussels can produce around 100 million eggs in a season. Mussel eggs are called spat
  • The spat floats in the water until it finds something to cling to - or, on a mussel farm, the spat is collected and held against the rows of rope using a cotton stocking.
  • When the spat grows into tiny mussels complete with shells there are millions of tiny mussels all trying to cling to the rope so the mussel farmers bring the ropes up onto the boat, remove the mussels and then spread the mussels out over more ropes.
  • When the baby mussels grow to be about 10 - 30 mm longs the ropes are lifted again and the mussels divided so they have more room to grow.
  • Each time they’re held in place by the cotton stocking until they can cling to the rope by themselves
  • Mussels take about 12 to 18 months to grow from tiny spat to about 100mm long and ready to be eaten.
A mussel eats tiny little sea creatures called plankton and things like algae. A mussel gets its food from the seawater by sucking water in and filtering all the tiny bits of food out of the water as it spits the water out again. To get enough to eat a mussel has to suck in and spit out about 350 litres of water – that’s like 5 good-sized bathtubs of water every day!
Mussels like fresh water they way that we do. Think about all the things that can end up in the sea – rubbish, oil, food scraps, raw sewerage – then think about your favourite kind of drink… with an empty chip packet in it and some paint, a old hamburger wrapper and a tissue! Would you like to drink it? I wonder how mussels and other sea creatures like the kind of water that humans make for them.
Next time you’re eating mussels from the shell have a look at the mussel close up. Does the shell still have the bristly beardy bit at the bottom of the shell? When you pull the mussel out of the shell can you see the little plug that it uses to hold onto the inside of the shell?
What colour is your mussel? Mussels with an orange tinge to some of the meat are female mussels and the plain coloured ones are male mussels.
What did one rock pool say to the others?
I’ve got bigger mussels (muscles) than you.
From JJ Mason

 1999 - 2006 © Treehut Limited