Large-flowered waterweed
Egeria densa
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Photo credit: Akvaryumda-https://www.akvaryumda.com/eledoa-egeria-densa/
Egeria densa - Large-flowered waterweed
Habitat:
Description:
Origin and Distribution:
Impacts:
Is it found in Northern Ireland?
How could it get here?
You can help by reporting any sightings: @ the Centre for Environmental Data & Recording (CEDaR) - Or via the iRecord App.
Prevent Spread
Current Legislation Position (Northern Ireland only):
Egeria densa - Large-flowered waterweed
Habitat:
- Lives mostly in canals but can be found in ponds and reservoirs up to 6m deep
- Can tolerate a range of pH and low oxygen conditions
Description:
- Submerged plant with large leaves
- Leaves have 3-7 whorls with bristles on the central nerves of the underside.
- Can be distinguished from Elodea species by the bristles and whorls of the leaf
- Spread slowly by fragmentation and human activity
Origin and Distribution:
- Native to south America
- First discovered in the Ashton canal in 1953 and there are now 20 small populations in Great Britian
Impacts:
- Outcompetes native species and disrupts natural predator-prey interactions
- If widespread can cause extensive environmental harm through erosion and preventing photosynthesis by clogging waterways and blocking light
- In addition to above if population size grows big enough it can affect fish populations and water flow.
- These impacts are only seen in countries and areas with extensive plant coverage and are otherwise unlikely
Is it found in Northern Ireland?
- Not currently in Northern Ireland
How could it get here?
- Could be introduced as an oxygenating plant
- Could be brought in with boats and spread
You can help by reporting any sightings: @ the Centre for Environmental Data & Recording (CEDaR) - Or via the iRecord App.
Prevent Spread
- Promote native species and biodiversity - use alternative, native plants
- Know what you are buying/growing and source native Irish seed and plants
- Do not swap plants and cuttings
- Clean plants before adding to ponds (dispose of water away from water courses)
- Follow control advice and watch out for hitchhikers - inspect new imported purchases for invasive pest and pathogens
- Clean equipment before moving between waterbodies
- Never collect plants from the wild
- Safe disposal of plant material and growing media
- Record all sightings.
Current Legislation Position (Northern Ireland only):
- Egeria densa is listed in Schedule 9 of the Wildlife (Northern Ireland) Order 1985 and as such, under Article 15 it is an offence to plant or otherwise cause this species to grow in the wild.