The plight of the pearl mussel

Scotland is the mussels' last European stronghold, supporting functional populations in over 50 rivers. But even here, few juveniles are being found and pearl mussel beds are under severe pressure. Individuals can grow to 140mm long, and burrow into the sandy beds of fast-flowing rivers and streams, often between boulders and pebbles. They reach reproductive maturity at around 12 years old. To thrive they need cool, well-oxygenated, soft water that is free of pollution. Changes in land use and farming practices are thought to have contributed to changes in water quality. By working with the people who manage the land, and engaging the expertise of officers from Catchment Sensitive Farming, they can balance the needs of food production and of the river ecology. For example, changes that protect the pearl mussel, such as fencing to keep farm animals out of the river, can also protect livestock by reducing foot infections.