The life of freshwater mussels
Where do they live?
Mussels bury themselves in the sediment at the bottom of rivers and lakes. A small amount of the shell sticks out so the animal can stick its siphons into the water to feed.
A large foot sticks out the bottom of the shell and acts as an anchor. Some mussels rarely move more than a few metres in their lifetime (which can be up to 200 years in some species!)
Young mussels have to be completely buried when they are tiny because their feet are too small to anchor them properly. If the sediment is very dirty from pollution the baby mussels suffocate.
What do they eat?
Mussels suck in water, filter food particles then spit the water out. It is this action that cleans our rivers and lakes for us. However, if the water is very polluted the mussel will die from 'eating' too many chemicals.
A large adult mussel can filter 38 litres (8 gallons) of water a day!
Do they taste good?
NO! - Many freshwater mussels grow quite large and are therefore too chewy for us to enjoy eating.
YES! - Many animals such as otters and racoons would disagree! They crack open the shells and feed on some mussels.
How do we get baby mussels?
- Male releases his sperm
- Female inhales it and mixes it with her eggs
- Glochidia (larval mussels) are released into the water...
- ...and attach to a certain type of fish
- After growing for a while on the fish the baby mussel drops off and buries in the sediment where it lives for the rest of its life.
This complex lifecycle relies on a healthy fish population!
Why are they dying out?
Because mussels filter the water they live in they are sensitive to changes in pollution levels of rivers and lakes. Too many chemicals kill them.
A small amount of mussels produce pearls, so they have been killed to obtain their treasure.
Changes to the river, such as damming, stop fish swimming upstream. Mussels cannot breed then, because they need fish for part of their lifecycle.
Why should we care?
A healthy mussel population shows that the water they live in and the surrounding land is healthy and free from too many chemicals. This makes them good environmental indicators and therefore very good for us to keep around!
Mussels filter out bacteria and other particles from the water, cleaning it for us.
A healthy mussel bed can stabilise rivers and lakes because large numbers of them together hold the sediment in place.
Help to improve our environment, save our mussels and they will do the same for us!
Article Date: 24 July 2007