River Lamprey (Lampetra fluviatilis)


Length: up to 50cm

Weight: up to 150g

Average life span: 4-8 years

Conservation status

Priority Species under the UK Post-2010 Biodiversity Framework.

When to see

January to December


Adult lamprey live and feed in coastal habitats and return to freshwater to spawn. During migration adult river lamprey move up stream at night and rest in cover during the day. Hatched lamprey spend several years buried in silt until they reach adulthood when they will migrate to sea. Spawning takes place from April to May on pebble and gravel substrates.

How to identify

Lamprey are an eel-like fish with a toothed, sucker-mouth. The river lamprey is a bluish-grey on the back and sides with a white underneath. It can be distinguished from other lamprey as it has two separate dorsal fins and a small number of teeth around its sucker. There are three species of lamprey in Scotland which are the river lamprey, the brook lamprey and the sea lamprey.  River lamprey are larger than brook lamprey, reaching 30 to 50cm in length but smaller than sea lamprey.

Lamprey in your Local River

The lamprey spends most of its freshwater live buried in the riverbed. They are particularly fond of soft, silt or sand to dig into. Barriers such as weirs and dams not only hold back water but also prevent materials like gravel silt and sand from moving downstream. The Riverlife Almond and Avon project is committed to easing the effects of man-made barriers on the rivers Almond and Avon. This not only allows access to upstream habitat but also allows sediment to move downstream creating and improving downstream habitat, especially for lamprey.

The Riverlife Almond and Avon project aims to remove barriers and restore habitat on the river Almond and the river Avon. This will aid fish migration and reproduction. Lampreys will benefit as the number of sites with suitable habitat increases.

The Riverlife project runs a volunteer electrofishing training program. This involves volunteers in the monitoring of freshwater species present at sites along the Almond and Avon rivers. It is during this monitoring that the trust science team comes into contact with lamprey. If you’re interested, get in touch.

Have you spotted a lamprey in your local river? We want to hear from you!  If you have, then send your photos or stories to us at riverlife@forthriverstrust.org.