Ecological survey calendar › Reptiles
When to survey for reptiles in Wales and England
Updated November 2026. Based on Natural England's current standing advice, including its season ending in mid-October.
Reptile surveys can be done from April to mid-October, but the best months are April, May and September, when reptiles bask more and are easiest to find. A presence or absence survey is normally seven visits in suitable weather.
Survey windows, sensitive periods and works timing
| Activity | Type | When | Notes |
|---|---|---|---|
| Presence or absence surveys (refugia) | Survey | Mar (not ideal); Apr to May; Jun to Aug (not ideal); Sep; early Oct (not ideal) | Seven visits in suitable weather, roughly 9 to 18°C, avoiding hot midday sun. Natural England's season ends in mid-October. |
| Hibernation | Sensitive period | Nov to Feb | Avoid ground works in banks, rubble and tree roots that could hold hibernating reptiles. |
| Two-stage habitat clearance | Works window | Apr; Sep to mid-Oct | While reptiles are active and can move away. Spring clearance must also allow for nesting birds. |
Optimal survey Possible, not ideal Sensitive period Works window
Timing depends on the site, the weather in a given year and what the planning authority and licensing body need. Upland and northern sites can run later. See every species group side by side on the ecological survey calendar.
About reptiles
Reptiles bask on sunny, sheltered edges such as rough grassland, scrub margins, banks and railway corridors, and hibernate underground through the winter.
Legal protection
The four widespread reptiles are protected from killing and injury under Schedule 5 of the Wildlife and Countryside Act 1981. Sand lizard and smooth snake are European protected species.
Licensing
Wales: No licence is needed for the four widespread species, but works must be planned to avoid killing or injury. Sand lizard needs a licence from Natural Resources Wales.
England: No licence is needed for the four widespread species, but works must be planned to avoid killing or injury. Sand lizard and smooth snake need a Natural England licence.
Practical tips
- Lay survey refugia a week or two before the first check so they can settle.
- Avoid checks in hot midday sun in July and August, when reptiles are hard to find.
Common questions
When is reptile survey season?
April to mid-October, with April, May and September the best months (Natural England standing advice; Froglife, 1999). Hot midday sun in July and August makes reptiles hard to find.
How many reptile survey visits are needed?
Seven visits in suitable weather, roughly 9 to 18°C, are normally needed to show presence or likely absence (Froglife, 1999). Refugia should be laid a week or two before the first check.
When can reptile habitat be cleared?
While reptiles are active and can move away, so April or September to mid-October, often in two stages. Spring clearance must also allow for nesting birds.
Do I need a licence for reptiles?
Not for the four widespread species, but the works must be planned to avoid killing or injuring them. Sand lizard and smooth snake are European protected species and need a licence.
Need a survey or advice on timing? Ecoleg's licensed ecologists programme surveys across Wales and England so the right work happens in the right season. Call 07356 123706.
Request a quoteSee the full calendarSources
- Froglife (1999) Reptile Survey: Advice Sheet 10.
- Natural England (2025) Protected species and development: advice for local planning authorities, survey timings table (accessed November 2026).
- Common professional practice; confirm for each site.
Updated November 2026. General guidance only: confirm timing for your site with a suitably qualified ecologist.