Twitter LinkedIn

Launch of a new national strategy to tackle invasive Floating Pennywort

Dr Emily Smith, Environment Manager at the Angling Trust and Chair of Link's INNS Group, discusses the new floating pennywort strategy and the importance of a strategic approach to INNS management.

This blog is part of our series for Invasive Non-Native Species Week 2021, an annual event to raise awareness of invasive species and how everyone can help to prevent their spread. Find out more about INNS Week 2021 and how to get involved here.

Whilst it is widely recognised that working at the catchment scale is the best approach to water management, invasive species control have often been undertaken at an insufficient scale and duration to cause long-term control or local eradication. All too often projects have ceased after a few years when funding runs out, allowing the remaining population to regrow and spread to the same extent as it was before, or a cleared site is re-invaded by a population located further upstream. This piecemeal approach to INNS management has been ineffective at controlling the spread of invasive species.

However, in the last few years momentum has been building calling for change. Wildlife and Countryside Link and other environmental groups have been calling for a more strategic approach to invasive species management and for adequate resources for control to occur on the appropriate scale and timeframe.

Partnerships have demonstrated the benefits of working together, and what can be achieved through persistence and coordinated action. These include collaborations between environmental groups and government bodies to tackle the invasive aquatic plant, Floating Pennywort.

What is Floating Pennywort?

First introduced as an ornamental pond plant in the 1990s, this freshwater plant grows some 20 cm a day and can form dense mats that cover the water’s surface. This blocks out the light out to the plants below causing loss of native habitat underneath floating stands and can cause localised reductions in oxygen levels. In some areas this may potentially increase the risk of flooding and prevent access to the water for recreation. Capable of spreading by small fragments the plant has rapidly in the wild and is still spreading despite efforts to contain the species. Climate change presents is likely to exacerbate this issue, with warmer climates anticipated to favour the growth and spread of the species. Unless effective management is undertaken it is likely this plant will spread across most of the country.

Shift to a more strategic approach

Over the last year a new national floating pennywort strategy has been developed bringing government agencies, environmental groups, and volunteers together to collectively control this species. In 2020 this strategic approach was trialled through a pilot study on the River Thames building upon existing effective collaborations to expand management across the Thames. Using the knowledge gained from this pilot and best practice collated from other partnerships around the UK, the strategy was refined and is now being launched nationwide. The strategy aims to provide a tool for communities to get involved in management of floating pennywort, and facilitate more coordinated action in priority areas across GB.

The Strategy presents a positive step towards more effective management of floating pennywort and will also develop networks and best practice that can be replicated for other invasive species control. However there remains a long road ahead. For this to be successful there needs to be clear communication and information sharing between groups, and proactive engagement of volunteers to monitor for new populations and tackle existing plant stands. Funding should also be provided to support the recruitment of coordinators and to provide equipment and training to volunteer groups.

Only through adequate investment can we expect this strategy to achieve the uptake necessary to reverse the spread of this species and achieve the ‘citizen’s army’ called for in the Environment Audit Committee.

To read more about the Strategy and to get involved visit the Floating Pennywort page located under the Local Action Group section on the Non-native Species Secretariat website.


Dr Emily Smith is Environment Manager at the Angling Trust.

Follow: @AnglingTrust

The opinions expressed in this blog are the author's and not necessarily those of the wider Link membership.