Adder (Vipera berus)
Key Details
| Taxonomic Groups: | Vertebrate > reptile > Reptile |
| Red List Status: | Near Threatened (Not Relevant) [NT(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: | Vipera berus |
| UKSI Recommended Authority: | (Linnaeus, 1758) |
| UKSI Recommended Qualifier: | (none specified) |
| Red List Citation: | Foster et al., 2021 |
| Notes on taxonomy/listing: | (none) |
Criteria
| Question 1: | Does species need conservation or recovery in England? |
| Response: | Yes |
| Justification: | This species has undergone substantial recent declines in parts of England, with county-level extinctions reported. Significant action is indicated in order to recover the species. |
| Question 2: | Does recovery/ conservation depend on species-specific actions? |
| Response: | Yes |
| Justification: | Species-specific action is necessary as some of the decline factors relate to particular elements of the species' ecology, and peculiarities in the way the species is considered in conservation practice. For example, management objectives for the species are often at odds with site objectives for co-occurring species and habitats. Other issues suggesting that species-specific approaches are needed include: public attitude implications arising from its venomous nature; persecution; impacts from non-native species such as gamebirds; reduction in prey availability. |
| 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 would likely benefit substantially from efforts to increase habitat diversity. The scale of benefits would depend on precisely what work was done. Downland habitat has on the past been overgrazed, often for botanical reasons, and adders have largely disappeared throughout much chalk grassland as a result of not enough cover, and associated predation. |
Species Assessment
| Current step on the Species Recovery Curve (SRC): | 5. Remedial action identified |
| Recovery potential/expectation: | Medium-high |
| National Monitoring Resource: | Combination - insufficient |
| Species Comments: | Further development of and investment in national monitoring is required. The National Reptile Survey (NRS, part of the National Amphibian and Reptile Monitoring Programme) started recently and will generate useful data with further uptake. Note: it is anticipated that recovery will be slower for adder than for other widespread reptiles. Note: Conservation translocations are likely to be indicated in certain circumstances. However, currently the generally accepted view is that from a national perspective, conservation translocations are secondary in importance to action to secure and recover existing populations. Hence no action is proposed in TSRA for conservation translocations, but if a longer list than three were feasible then an action on translocation (establishing and delivering a national strategy) would likely be recommended. |
Key Actions
Key Action 1
Proposed Action: Adder populations have become fragmented leading to small, isolated and, in some cases, potentially genetically impoverished populations. Explore solutions for the management and creation of habitat, to relieve key threats including fragmentation, recreational disturbance, persecution, and conflicts in management objectives for co-occurring species.
Action targets: 6. Recovery solutions trialled
Action type: Scientific research
Duration: 6-10 years
Scale of Implementation: ≤ 10 sites
High priority sites: Adders appear to be in general decline throughout much of England's distribution (and beyond). It is important to identify populations at risk and improve habitat connectivity. This would help to ensure colonies are more robust with the predicted effects of climate change.
Comments: This research would involve experimental habitat management, trialling solutions for a number of threats to adders. Issues to address include disturbance, persecution, road mortality, loss of connectivity, vulnerability of hibernation features, conflicts in site objectives with co-occurring species. The action will also consider the likely impacts of a changing climate and the implications for management. This action could potentially be brigaded with the similar action for grass snake, slow-worm and common lizard, as there is an overlap in some issues.
Key Action 2
Proposed Action: Identify, and consider the potential to designate, sites as SSSIs with widespread reptiles as an interest feature (reptile assemblage).
Action targets: 5. Remedial action identified
Action type: Site protection
Duration: >10 years
Scale of Implementation: National
High priority sites:
Comments: Identification of ≤ 20 SSSIs. Identification of around 10 sites per county or equivalent area for non-statutory designation (most likely Local Wildlife Sites). This is proposed as a 'brigaded action' for the four widespread reptile species, where many of the sites would be designated for several of these species. For widespread reptiles (excluding adders) designation on SSSIs can only be notified as part of a reptile assemblage feature. The revised (Bernhard et al., 2022) SSSI guidance for amphibians and reptiles provides better guidance for boundary setting, which will facilitate designation of larger SSSIs than previously. Aside from its inherent benefits now, this action would help future-proof the protected site series for reptiles in the face of a changing climate.
Key Action 3
Proposed Action: Different activities and habitat types pose specific opportunities and threats for the species, and practical guidance will help to maximise conservation benefit and to minimise negative impacts. Develop guidance and training courses for specific themes of significance to the conservation of this species, including: management of agricultural land ; management of especially favourable habitats such as linear features like road verges, and improving connectivity with the wider countryside; forestry; re-wilding; protected sites; development impacts; disturbance impacts; wildfire prevention and response.
Action targets: 7. Best approach adopted at appropriate scales
Action type: Education/awareness raising
Duration: 3-5 years
Scale of Implementation: National
High priority sites:
Comments: Brigaded action across four widespread reptile species (slow-worm, common lizard, grass snake and adder). This action would include simple guidance leaflets, detailed guidance (including a web-based resource), road shows, videos, and training courses. To be developed over a period of three years. Over a longer period of time these resources would be updated to take account of new research and practice (including from work proposed in Action 1), and also as pressures and potential conservation measures change. Brigaded action as many of the issues will be similar across the four widespread reptile species; however, species-specific guidance will be required and incorporated as relevant.
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.