 |
| American Mink |
Populations of American mink in the United Kingdom were first established when individuals escaped or were released from fur farms. A voracious and adaptable predator, the American mink kills domestic poultry, causes damage to fisheries and predates native species. The American mink can act as a vector of disease, which it may spread to native species.
 |
| Floating Pennywort |
Growing at a rate of up to 20cm per day, this plant may quickly dominate a water body forming thick mats and impeding water flow. May out-compete native species by blocking out light, causing deoxygenation, obstructing air breathing insects from reaching the water surface and reducing water temperatures.
 |
| Canada Goose |
Large flocks of Canada geese create an enormous quantity of droppings, which foul parks and golf courses. The droppings can also pollute water bodies, causing health risks to humans. In areas where Canada geese are found in vast aggregations they can cause damage to riverbanks and waterside vegetation.
 |
| Himalayan Balsam |
The Himalayan balsam produces a large amount of nectar, which makes it much more attractive to pollen-spreading insects than neighbouring native species. Due to its large size, the Himalayan balsam outcompetes native species for light and space. The rapid growth of the Himalayan balsam and its tendency to grow around water can lead to flooding and other changes in the ecosystem’s water cycle.
 |
| American Bullfrog |
It is thought that the American bullfrog was introduced to the UK through the release of unwanted pets or accidental importation with aquatic plants or fish. Classed as one of the 100 worst invasive species in the world by the IUCN, the American bullfrog threatens native species, through competition, predation and disease transmission. More than £100,000 has been spent on control and monitoring of the American bullfrog in the UK so far, with over 9,000 individuals having been removed from the wild.
 |
| Killer Shrimp |
The freshwater Killer Shrimp kills a wide range of British species including young fish. It is rapidly spreading, is one of the most invasive species in Europe, and can survive for up to 15 days at a time. They are usually between 10-20mm in length but can grow up to 50mm. They have distinctive cone-shaped bumps on their tale and usually have striped backs.
 |
| Zebra Mussels |
Very small animals, from 30-50mm in length. They have a characteristic ‘D’ shape. They are found in rivers, canals and lakes, usually in large clusters and can affect lock gates and block pipe work. They rapidly take nutrients from the water, negatively altering ecosystems and suffocating native species.
 |
| Nuttall's Waterweed |
Nuttall's Waterweed is commonly found in more nutrient-rich water. The waterweed produces dense growth in slow flowing rivers, drainage channels and canals can impede flow and exacerbate flooding. It can replace native aquatic plant species and reduce biodiversity in lakes and ponds and interfere with recreational activities such as angling and boating.
 |
| Signal Crayfish |
If you see any of these species, please report it to iRecord at http://www.brc.ac.uk/irecord/. They can be very harmful to the local ecology. Thank-you.
Keep linked in with what we're up to via social media:
Twitter - https://twitter.com/WellandTrust or @WellandTrust
Facebook - https://www.facebook.com/WellandTrust?ref=hl
