National Amphibian and Reptile Recording Scheme – NARRS Reptile Surveys.

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National Amphibian and Reptile Recording Scheme – NARRS

Reptile Surveys

How to survey for reptiles

• Reptiles warm up by basking or lying under warm objects

• Reptile survey should (ideally) combine two techniques:

• Visual search• Artificial refugia

• All species can be found using visual search• But artificial refugia greatly increase chances of

detection (for some species)

How to survey for reptiles

• Refugia important surveying some than others:• Slow-worms, smooth snakes – surveys should

involve refugia (rarely seen otherwise)• Adders, grass snakes – refugia useful (but can

be found by visual search)• Common lizards, sand lizards – refugia can be

useful (but must use visual search as well – otherwise miss lots)

• Always search when walking between refugia• Practice really does help!

When to survey for reptiles – best time of year

• Best time is the spring (especially April)• Reptiles most active and visible • Getting into breeding condition• Cool weather – need to bask for longer at this

time of year• As the spring becomes summer, survey only

possible in short periods• As cooler autumn arrives - survey conditions

improve again

When to survey for reptiles – best time of year

Bad BadBest GoodVariable/ Poor

When to survey for reptiles – best time of year

Sand lizard

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1 2 3 4 5 6 7 8 9 10 11 12

Month

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Sand lizard sightings per month

Definite spring peak

When to survey for reptiles – best time of day

• Early spring - middle hours of the day (c.11am-3pm)

• Late spring – mid morning (c.9-11am) and late afternoon (c.4-6pm)

• Summer – short periods in morning (c.7-9am) and evening (6-8pm); hot weather can produce totally negative results

• Autumn similar to spring timings• However, time of day varies with weather too

When to survey for reptiles – best weather conditions

• No clear-cut way of defining right/wrong weather • Strong wind/heavy rain not good• Any other conditions can be good (depending on

the time of year & time of day)• Early spring/late autumn – sunny or partial cloud• Air temperature 10-20°C• Late spring/early autumn – sun/cloud and bright

overcast forces reptiles to bask longer • Sunshine after rain is ideal• First sunshine after dull overcast weather• Extended periods of hot dry weather - not good

Fff

Weather vs time of day vs season…

Mar Apr May Jun July Aug Sept Oct

1900

1700

1500

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0700

Visual search - where and how to spot reptiles

• Walk slowly, scanning sunny sides of vegetation

• Keep sun behind you or to your side• Tune your eye in to vegetation interfaces• Often places where reptiles bask along

edges• Seldom far from dense cover for

protection

Walk slowly, scanning the ground as you go

Visual search - where and how to spot reptiles

Visual search - where and how to spot reptiles

Look for sheltered spots that act as suntraps

Visual search - where and how to spot reptiles

Junction between vegetation types/heights

Visual search - where and how to spot reptiles

Varied height structure – look in short patches

Visual search - where and how to spot reptiles

Edge of gorse scrub, meeting rough grass

Visual search - where and how to spot reptiles

Moss or lichen patches among taller vegetation

Artificial refugia

• Corrugated metal – best• Roofing material/felt – good• Rubber car mats, plastic sheeting, carpet – ok• Size approx half a square metre (70 x 70cm)• Choose sunny locations away from public view and

livestock• Press down close to the ground• Deep cover or edge of dense vegetation• Not on bare ground/sparse cover • Lift and replace refugia carefully taking care not to

squash retreating animals• Use a stick or adder-proof glove if necessary to

ensure safety

Artificial refugiaCorrugated metal sheets (‘tins’) – cut to size

Artificial refugiaOld rusty tins often more effective

Artificial refugiaCorrugated bitumen-based roofing material (onduline)

Artificial refugiaRoofing felt

Artificial refugiaRoofing slate

Pre-existing objects acting as refugiaWooden board

Pre-existing objects acting as refugiaDiscarded wheels, tyres, scrap etc.

Pre-existing objects acting as refugiaDiscarded clothing, plastic, rubber etc.

NARRSPreliminary square assessment

• Consult an Ordnance Survey map

(Landranger map 1:50,000 or Explorer 1:25,000 scale)

• Or an online map of your square (www.streetmap.co.uk: enter 4-fig grid ref e.g. SK1294 and zoom out once)

• Aerial photo useful (www.multimap.com: needs 6-fig grid reference e.g. SK120940 and click aerial button)

• Identify key areas most likely to support reptiles

Preliminary square assessmentLooking up your square on www.streetmap.co.uk

Preliminary square assessmentLooking at aerial photo on www.multimap.com

Landowner permissions

• Always seek permission from landowners/ tenants before entering private land

• Always seek permissions to survey, whether public or private land

• As a courtesy, even seek permission to survey on Open Access land

• See the guidance at www.narrs.org.uk

Further square assessment

• If permission is not granted for enough (key) areas, request another square

• Plan a walking route that takes in all key areas

(representing best habitat, and surveyable in 2-3 hrs)

• Walk your square• Lay artificial refugia (if suitable places, safe,

permitted by landowners)

Survey visits• Between March-June, ideally April-May:• Choose suitable conditions (time of day,

weather)• Cover key areas in a survey lasting no more

than 3 hours • Visual search and check refugia • Fill in your survey form (visit details, survey

effort, reptiles seen – use ID Guide if needed)• Try to make four visits

(ideally, the fourth visit should be at least 4 weeks after refugia were laid)

• More visits if you like…

Completion/data submission

• As soon as possible after survey visits:

• Submit your results online at www.narrs.org.uk

or send your survey form to the ARC

• Remove refugia

• Feedback to landowners if interested

Licensing

• A licence is required to survey sand lizards or smooth snakes

• You can be covered by the ARC’s survey licence, subject to training or experience

• ask your trainer to pass your details to ARC if you think you will encounter protected reptiles during your surveys!

Good luck with your survey!

www.narrs.org.uk

Photographs

• Photographs used in this presentation are by Lee Brady, Julia Carey, Jon Cranfield, Terry Elborn, Chris Gleed-Owen, Fred Holmes, Paul Stevens and John Wilkinson

• Copyright of all photographs remains with the photographers and ARC

• These photographs should not be used for purposes other than NARRS training without the permission of the photographers.