Uploaded August 2026 | Updated September 2026, 2 hours ago
Beavers are herbivorous and have been recorded eating more than 400 species of plants. Their diet changes with what is available locally, so they sometimes browse invasive non native plants, including Rhododendron ponticum, Himalayan balsam, Japanese knotweed and more.
At this site, beavers were feeding on Japanese knotweed, but this should not be considered control.
Beavers are messy eaters, and vegetation can break off and be left in the water as they feed. This is a concern with invasive plants such as Japanese knotweed and Himalayan balsam. Knotweed can regenerate from very small pieces, so fragments could be carried downstream and establish. Beavers may also move vegetation around their territory, including upstream.
But beavers shouldn’t have to interact with these species in the first place.
Invasive plants are present because of human introduction and spread, and managing them remains a human responsibility. Beavers may browse or submerge invasive species, but they cannot be relied upon to solve the problem or be seen as the cause of their presence. We need sustained, catchment scale management, working systematically from source to sea over a number of years.
That is what the Scottish Invasive Species Initiative has achieved in this area of The River Tay catchment. Years of targeted treatment, have greatly reduced its abundance and allowed native vegetation to recover. The resident beaver family now has a much wider range of native plants available to browse.
At another site in Britain, increased water levels created by beavers have also flooded areas of invasive rhododendron, causing some plants to die back. These effects are interesting, but should never replace active management.
You can also help stop invasive species moving between rivers and wetlands by following Check, Clean, Dry. Check clothing, footwear and equipment for plant material and mud, clean them thoroughly, and allow them to dry completely before visiting another waterbody.
Beavers are herbivorous and have been recorded eating more than 400 species of plants. Their diet changes with what is available locally, so they sometimes browse invasive non native plants, including Rhododendron ponticum, Himalayan balsam, Japanese knotweed and more.
At this site, beavers were feeding on Japanese knotweed, but this should not be considered control.
Beavers are messy eaters, and vegetation can break off and be left in the water as they feed. This is a concern with invasive plants such as Japanese knotweed and Himalayan balsam. Knotweed can regenerate from very small pieces, so fragments could be carried downstream and establish. Beavers may also move vegetation around their territory, including upstream.
But beavers shouldn’t have to interact with these species in the first place.
Invasive plants are present because of human introduction and spread, and managing them remains a human responsibility. Beavers may browse or submerge invasive species, but they cannot be relied upon to solve the problem or be seen as the cause of their presence. We need sustained, catchment scale management, working systematically from source to sea over a number of years.
That is what the Scottish Invasive Species Initiative has achieved in this area of The River Tay catchment. Years of targeted treatment, have greatly reduced its abundance and allowed native vegetation to recover. The resident beaver family now has a much wider range of native plants available to browse.
At another site in Britain, increased water levels created by beavers have also flooded areas of invasive rhododendron, causing some plants to die back. These effects are interesting, but should never replace active management.
You can also help stop invasive species moving between rivers and wetlands by following Check, Clean, Dry. Check clothing, footwear and equipment for plant material and mud, clean them thoroughly, and allow them to dry completely before visiting another waterbody.
