Freshwater pearl mussel

Freshwater pearl mussels are similar in shape to common marine mussels but grow much larger and live far longer.

They can grow as large as your hand and live for more than 100 years, making them one of the longest-lived invertebrates. A mussel may very occasionally bear a pearl.

The freshwater pearl mussel is a protected species throughout its range in Scotland therefore you must not wilfully disturb or touch it.

Report suspicious activity.You should call Police Scotland on 101 urgently if you see any suspicious activity in or near a river that may contain freshwater pearl mussels.

How to be responsible when watching wildlife >

Discover more about the Freshwater Pearl Mussel

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When to see

During the early summer when water levels are low, oystercatchers that have travelled inland to breed sometimes find and feed on the pearl mussels leaving the empty shells on the riverbank.

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Where to see

These mussels live on the beds of clean, fast-flowing rivers, where they can be buried partly of wholly in coarse sand or fine gravel. They feed by drawing in river water and ingesting fine particles of organic matter. An adult freshwater pearl mussel can filter more water in a day than an average person uses to shower. They are dark brown to black in colour.

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Did you know?

An adult mussel can live for more than 100 years. Freshwater pearl mussels were once common in the clean Scottish rivers and streams, over-fishing and pollution have destroyed most stocks. Current research is developing methods for mussels to propagate in salmon and trout fisheries to provide stocks to seed new mussel beds in protected rivers.

Binoculars Icon Blue
When to see

During the early summer when water levels are low, oystercatchers that have travelled inland to breed sometimes find and feed on the pearl mussels leaving the empty shells on the riverbank.

Map Icon Blue
Where to see

These mussels live on the beds of clean, fast-flowing rivers, where they can be buried partly of wholly in coarse sand or fine gravel. They feed by drawing in river water and ingesting fine particles of organic matter. An adult freshwater pearl mussel can filter more water in a day than an average person uses to shower. They are dark brown to black in colour.

Book Icon Blue
Did you know?

An adult mussel can live for more than 100 years. Freshwater pearl mussels were once common in the clean Scottish rivers and streams, over-fishing and pollution have destroyed most stocks. Current research is developing methods for mussels to propagate in salmon and trout fisheries to provide stocks to seed new mussel beds in protected rivers.

Binoculars Icon Blue
When to see

During the early summer when water levels are low, oystercatchers that have travelled inland to breed sometimes find and feed on the pearl mussels leaving the empty shells on the riverbank.

Map Icon Blue
Where to see

These mussels live on the beds of clean, fast-flowing rivers, where they can be buried partly of wholly in coarse sand or fine gravel. They feed by drawing in river water and ingesting fine particles of organic matter. An adult freshwater pearl mussel can filter more water in a day than an average person uses to shower. They are dark brown to black in colour.

Book Icon Blue
Did you know?

An adult mussel can live for more than 100 years. Freshwater pearl mussels were once common in the clean Scottish rivers and streams, over-fishing and pollution have destroyed most stocks. Current research is developing methods for mussels to propagate in salmon and trout fisheries to provide stocks to seed new mussel beds in protected rivers.