Most Unwanted: Parrots feather
Myriophyllum aquaticum
Habitat: Freshwater
Threat: Clogs waterways and negatively impacts on native species and ecosystems
Status: Established
This is an aquatic invasive species that has become invasive in Britain since the 1960’s and is now present at a number of sites around Ireland. This species represents a significant threat to ponds and lakes.
What is it?
This species is similar to a native species of Myriophyllum, otherwise known as water milfoil. It is an aquatic invasive plant but has been recorded to survive in dried out ponds as well as on dry banks in Britain. So far, only female plants have been recorded in Britain and Ireland. As a result this species reproduces solely by fragmentation. The species gets its name from the feather like leaves that arranged in groups around the central stem. Parrots feather has both submerged and emergent leaves that grow above the surface of the water.
Garden centres are also known to sell similar species that are also recognised invasive species. These may be labelled as M. brasiliense, or M. propernaciodes, or M. propium.
Impact
This species is capable of out competing native macrophytes, reducing species diversity. There is also a possibility that this species will clog waterways leading to problems for drainage and access.
Where is it from?
The species is native to South America where both male and female forms are known.
Where is it in Ireland?
In Northern Ireland Parrots Feather has only been recorded at one site in the Ards Peninsula, County Down. In the Republic of Ireland Myriophyllum aquaticum has been recorded at a number of sites with 5 new sites appearing since 2000. The number of garden ponds with this species is unknown.
How did it get here?
The species was brought to Ireland as a garden pond plant.
How is it spreading
The species is known to escape from garden ponds as it readily fragments leading to the establishment of new colonies in the wild.
Disposal of garden waste incorrectly near waterways has also allowed this species to become more widespread.
There is a very real potential for this species to be spread accidentally by fragments attaching to footwear or fishing equipment including boats and nets.
What you can do
Do not buy invasive aquatic plants.
Dispose of garden waste in a responsible manner.
Report all sightings.
Additional reading
Habitas Invasive Alien Species in Northern Ireland
