For some time now, a large range of exotic plants and animals have been available to the public in aquatic stockists. The majority of these species are not able to live in the UK outside of gardens or highly sheltered environments. However, some species escape or are deliberately released from cultivation and have become pests in the wider environment. With no natural predators and a benign climate they can out-compete our native plant and animal species. Invasive non-native plant species occupy the habitats of native plants, block up waterways and rapidly reach nuisance proportions, requiring extremely expensive remediation works.
In 2014 five species of aquatic invasive plant were banned from sale. The species have been chosen because of their negative effects on the environment and economy:
- Floating water primrose (Ludwigia grandiflora, Ludwigia uruguayensis and Ludwigia peploides)
- Floating pennywort (Hydrocotyle ranunculoides)
- Parrots feather (Myriophyllum aquaticum)
- Australian swamp stone-crop (Crassula helmsii)
- Water fern (Azolla filiculoides)
If you ever see these species being sold in the UK, you should report it to the police.
Other species that you should avoid include:
- Curly waterweed (Lagarosiphon major)
- Canadian pondweed (Elodea canadensis)
- Nuttall's pondweed (Elodea nuttallii)
- Water hyacinth (Eichhornia crassipes)
- Water lettuce (Pistia stratiotes)
To avoid accidentally spreading non-native invasive species into the wider countryside, never move plants or animals between ponds and always compost any plant material that's been removed.