Pool Frog (Pelophylax lessonae)
Key Details
| Taxonomic Groups: | Vertebrate > amphibian > Amphibian |
| Red List Status: | Critically Endangered (Not Relevant) [CR(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: | Pelophylax lessonae |
| UKSI Recommended Authority: | (Camerano, 1882) |
| UKSI Recommended Qualifier: | (none specified) |
| Red List Citation: | Foster et al., 2021 |
| Notes on taxonomy/listing: | Northern Clade Pool Frog |
Criteria
| Question 1: | Does species need conservation or recovery in England? |
| Response: | Yes |
| Justification: | This species went extinct in the 1990s and was reintroduced in 2005. It currently occupies a fraction of the natural range (considered to be an area within Lincolnshire, Cambridgeshire, Suffolk and Norfolk). Efforts are required to maintain and enhance existing populations, and to restore the range. The species is considered conservation dependent in that it requires particular habitat conditions that are difficult to create and require ongoing intervention to maintain. |
| Question 2: | Does recovery/ conservation depend on species-specific actions? |
| Response: | Yes |
| Justification: | Generic actions would not address the recovery of this species as it is a habitat specialist with complex requirements. Reintroduction is a key element of recovery. |
| 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: | Possibly, but it depends on precisely what is done. The efforts likely have a low chance of incidentally creating and maintaining the conditions needed by this species, given it has rather specialist requirements and therefore targeted habitat management is required for the conservation of this species. Potential habitats could be restored and managed for future releases to restore the species to its historic range. |
Species Assessment
| Current step on the Species Recovery Curve (SRC): | 6. Recovery solutions trialled |
| Recovery potential/expectation: | Medium-high |
| National Monitoring Resource: | Structured - sufficient |
| Species Comments: | With captive breeding, it is hoped that new sites can be populated but these will need to be monitored to determine levels of success. |
Key Actions
Key Action 1
Proposed Action: The species requires recovery from recent extinction, with only two locations occupied as of 2024. Establish additional populations by translocation to new sites from a reintroduction programme managed to good practice. This to involve: review of pool frog reintroduction strategy, captive breeding and/or rearing, identification of additional sites to establish additional populations, addressing issues for reintroduction by following good practice, undertake appropriate habitat management and/or restoration at release sites.
Action targets: 6. Recovery solutions trialled
Action type: (Re-)introduction
Duration: >10 years
Scale of Implementation: ≤ 10 sites
High priority sites: Thompson Common, one confidential location + other potential new sites in Brecks. Expansion to historic range a possibility
Comments: ARC is delivering a long-term programme to restore the northern pool frog in England, following its extinction; this involves a range of partners including Natural England. Further work is needed to scale up reintroduction efforts. Note: NE recently (March 2024) confirmed SRP funding for a trial captive facility, with contributions also from Banham Zoo, ARC and ZSL. It is understood the funding is confirmed only for 1 year; ongoing funds (not necessarily from NE) will be required in order to make this effective.
Key Action 2
Proposed Action: Create and restore habitats in the vicinity of existing populations to generate robust meta-populations of pool frogs. Possibly consider other sites within historic English distribution to restore for future re-introduction.
Action targets: 6. Recovery solutions trialled
Action type: Habitat creation
Duration: >10 years
Scale of Implementation: ≤ 10 sites
High priority sites: Thompson Common, one confidential location + other potential new sites in Brecks. Expansion to historic range a possibility
Comments: This should be co-ordinated with work to deliver Action 1 (reintroductions). Creation and restoration of suitable sites in partnership with other organisations (as appropriate).
Key Action 3
Proposed Action: Research habitat use to better inform site management and future site selection.
Action targets: 4. Autecology and pressures understood
Action type: Scientific research
Duration: 3-5 years
Scale of Implementation: Not applicable
High priority sites: Thompson Common & a confidential location.
Comments: A detailed research prioritisation exercise undertaken by ARC in 2023, involving key stakeholders, identified habitat use as the main evidence gap hindering progress. In summary, the issues relate to our understanding of breeding sites and terrestrial habitat use including overwintering. A study would focus on two sites, but results would be more broadly applicable. Whilst research on these issues has been done overseas, the situation may vary in England, and the lack of knowledge is causing issues for maintaining the existing populations and for selecting new reintroduction sites. This includes information on the terrestrial phase of the species, such as hibernation sites. Also further information would be useful on understanding the movement of animals and the potential effects of predation.
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.