Whorled Water-milfoil (Myriophyllum verticillatum)
Key Details
| Taxonomic Groups: | Vascular plant > flowering plant > Aquatic plant |
| Red List Status: | Vulnerable (Not Relevant) [VU(nr)] |
| D5 Status: | Included in the baseline Red List Index for England (Wilkins, Wilson & Brown, 2022) |
| Section 41 Status: | (not listed) |
| Taxa Included Synonym: | (none) |
| UKSI Recommended Name: | Myriophyllum verticillatum |
| UKSI Recommended Authority: | L. |
| UKSI Recommended Qualifier: | (none specified) |
| Red List Citation: | in Stroh et al., 2014 |
| Notes on taxonomy/listing: | (none) |
Criteria
| Question 1: | Does species need conservation or recovery in England? |
| Response: | Yes |
| Justification: | A submerged aquatic perennial of clear lakes, streams, canals and ditches with good water quality, mainly in low-lying parts areas of England such as the East Anglian Fens, Somerset Levels, Norfolk Broads etc. Outside Fenland it has undergone declines presumably due to the reductions in water quality and as a consequence it was assessed as NT in England (Stroh et al., 2014). |
| Question 2: | Does recovery/ conservation depend on species-specific actions? |
| Response: | Yes |
| Justification: | The recovery of this aquatic plant will require targeted measures to improve water quality and reduce disturbance levels at key sites and potentially reintroduction to historic sites. |
| Question 3: | At a landscape scale, would the species benefit from untargeted habitat management to increase habitat mosaics, structural diversity, or particular successional stages? |
| Response: | Yes |
| Justification: | This aquatic plant would benefit from improvements to water quality in catchments where it occurs through reduction of nutrient inputs from agricultural land and other land uses. |
Species Assessment
| Current step on the Species Recovery Curve (SRC): | 2. Biological status assessment exists |
| Recovery potential/expectation: | Medium-high |
| National Monitoring Resource: | Opportunistic - insufficient |
| Species Comments: | Aquatic plants are generally under-recorded by opportunistic (citizen science) recording. |
Key Actions
Key Action 1
Proposed Action: Research is needed to understand the key ecological conditions that this species requires in particular water quality, water pH, etc. as well as the means by which it regenerates.
Action targets: 4. Autecology and pressures understood
Action type: Scientific research
Duration: 2 years
Scale of Implementation: National
High priority sites:
Comments:
Key Action 2
Proposed Action: Utilise the results of the scientific review of its ecological requirements to assess the condition of key historic sites with a view to restoring the ecological conditions it needs to persist.
Action targets: 5. Remedial action identified
Action type: Habitat management
Duration: 3-5 years
Scale of Implementation: ≤ 10 sites
High priority sites:
Comments:
Acknowledgment:
Data used on this website are adapted from Threatened species recovery actions 2025 baseline (JP065): Technical report and spreadsheet user guide (Natural England, 2025). Available here.