Holly-leaved Naiad (Najas marina)
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: | Najas marina |
| 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: | No |
| Justification: | Although assessed as VU by Stroh et al. (2014) due to a historic decline and a restriction to less than 5 sites it now exceeds this due to its colonisation of new sites. It has been recorded in >10 recently including spread to new sites in The Broads, 1 site in Norfolk outside The Broads and 2 sites in Sussex (Arundel Wetland Centre and Darwell Reservoir). Although the origin of these populations is unknown it is suspected of having colonised naturally and then persisted due to climate change. It is therefore likely to increase further in the future assuming further improvements in water quality inside and outside its core areas, as well as the restoration of wetland complexes. |
| Question 2: | Does recovery/ conservation depend on species-specific actions? |
| Response: | No |
| Justification: | This species appears to be recovery due to landscape-scale factors rather than species-specific conservation. |
| 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 species appears to have spread in the last decade due to improvements in water quality within The Broads, wetland restoration work (e.g. The Norfolk Pond Project). and climate change. Such landscape initiatives are likely to benefit it further in the future. |
Species Assessment
Not relevant as no Key Actions defined.
Key Actions
No Key Actions Defined
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.