Wear Rivers Trust

Pollution Incident Hotline: 0800 80 70 60



The Wear Rivers Trust is currently working to map and manage invasive non-native species (INNS) throughout
the Wear catchment. As part of our Wear Invasive Non-Native Species (WINNS) project we are;

   • Gathering INNS records from the public and other organisations

   • Co-ordinating volunteer walkover surveys

   • Producing INNS coverage maps for the whole Wear and for individual priority sub-catchments

   • Training people to identify and control INNS

   • Strategically tackling INNS in partnership with others.

Learn More

For more information on the various INNS please follow the link below to the GB Non-Native Species Secretariat.


We are currently producing a strategy for tackling INNS across the whole Wear catchment. We will capture the current distribution and propose future activity in a WINNS management plan. We’re linking with other organisations working towards the same goal, sharing knowledge and resources to be more effective. There are several other invasive species which pose a threat to UK watercourses and we will use a risk based approach to prioritise our work in future.


Efficient and effective management

Where appropriate we are using volunteer effort to control INNS  in the Wear.  We seek all permissions and liaise with stakeholders to manage INNS where we can achieve the maximum benefit. The management of INNS is important because of the negative impact they can have upon the environment. INNS often form monocultures and outcompete native species which have evolved to suit the Wear catchment. 

Japanese knotweed (Fallopia japonica) is a perennial weed that spreads rapidly. In winter the plant dies back to ground level but by early summer the bamboo-like stems emerge from rhizomes deep underground to shoot to over 2.1m (7ft), suppressing all other plant growth. Eradication requires determination as it is very hard to remove by hand or eradicate with chemicals. Knotweed can cause damage to built structures as it can grow through masonry and even concrete. It can remain dormant for several years and can vegetate from rhizomes. Fortunately it’s seeds are not viable in the UK.

Japanese knotweed identification guide

Himalayan balsam (Impatiens glandulifera) is a relative of the busy Lizzie, but reaches well over head height, and is a major invasive weed, especially on riverbanks and waste land, but can also invade gardens. It grows rapidly and spreads quickly, smothering other vegetation as it goes. It spreads by seed dispersal, which are spread several metres by a catapulting action from the ripe seed pods. In winter it dies back, leaving river banks bare and more susceptible to erosion.

Himalayan balsam identification guide

Giant hogweed (Heracleum mantegazzianum) is widespread in lowland GB, and is invasive along lowland rivers and on waste land.   This umbellifer (member of the cow-parsley family) has flowering stems typically 2-3 m high bearing umbels of flowers up to 80 cm in diameter. The basal leaves are often 1 m or more in size. It is similar in appearance to the smaller native Hogweed (Heracleum sphondylium). Giant hogweed contains sap which, upon contact with bare skin can cause severe burns when exposed to the sunlight. 

Giant hogweed identification guide


Many freshwater and riparian invasive species are able to spread from one area to another hidden in our clothing, footwear or equipment. One way that we can reduce the likelihood of this happening is by following simple biosecurity measures, such as DEFRA’s Check, Clean, Dry protocol:

CHECK – Check clothing, footwear (including treads) and equipment for mud, plant material (e.g. seeds) or small aquatic animals before leaving the site and remove anything found while still there.

CLEAN – Clean everything thoroughly in hot water as soon as possible, making sure to include damp or hard to reach areas (if you are able to, do this while still at the site).

DRY – Leave everything to dry for as long as possible before using at a new site. Bear in mind certain species can survive for up to 2 weeks in damp conditions.

If you are planning to visit multiple sites, another useful tip is to make sure any sites where invasive species are not currently found (particularly any of significant ecological importance) are visited first while those where invasive species presence has been confirmed are left until last. Following this process will reduce the likelihood of invasive species being inadvertently introduced to new areas.

More information about biosecurity is available at http://www.nonnativespecies.org/checkcleandry/index.cfm


Wear Rivers Trust is now working with other organisations within the North East to create a region-wide INNS strategy to cohesively tackle invasive species across the Tweed, Northumberland Rivers, Tyne, Wear, and Tees catchments. This involves collaborating with the four other Rivers Trust associated with these areas, as well as Durham Wildlife Trust, the Environment Agency, Northumbrian Water and Environmental Records Information Centre (ERIC) North East, to compile invasive species records and share information. By learning from each other and pooling resources, it is hoped that a more efficient strategy for tackling INNS can be devised, increasing the likelihood that these species may one day be eradicated from the region.

Some other species to be on the lookout for in the Wear catchment and wider North East area include:

· Curly Waterweed

· Floating Pennywort

· Zebra Mussel

· American Skunk Cabbage

· Giant Japanese Knotweed

· Himalayan Knotweed

· Killer Shrimp*

These are currently less common in the region than Japanese Knotweed, Himalayan Balsam and Giant Hogweed, but must be monitored and sightings responded to quickly to prevent them becoming common and causing widespread damage.

*Killer shrimp is a GB alert species due to the devastating effect it could have on UK aquatic ecosystems. Any sightings of this species must be reported to the Centre for Ecology and Hydrology so the nation-wide response protocols which have been developed can be enforced quickly (more information is available here).

Other species to be aware of: 

Pink Salmon, find out more here 

Asian Hornet, find out more here 



If you would like to support this project and help us continue this work, please click the link below to visit our donation page.