narrs amphibian surveys and field techniques

Two- metre sections; The torch should be moved away from the bank and back, to cover the area of the pond in the two- metre segment; Repeat for all the ...
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1.National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

2.Aquatic habitat Survey Methods Egg searching Netting Torching Bottle trapping Refuge searching Pitfall trapping

3.Egg Searching Submerged vegetation Great crested newt Smooth/palmate newt

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7. Focus on newly-laid eggs Harder to identify once larva takes shape

8.Egg Searching Advantages Disadvantages Quick method Little value for determining population size Great crested newt eggs are distinctive No equipment is needed Low level disturbance

9. Netting A good net with a rigid frame and a mesh of approximately 2-3mm costs around £50-60 including delivery

10.Netting Effort Work around the pond perimeter Net along two-metre lengths of shoreline Agitate the net through aquatic vegetation in two-metre arc Netting open water is less effective than netting in vegetation

11.Great crested newt larva Smooth newt larva

12.Overwintering larva

13.Netting Advantages Disadvantages Useful for catching great crested newt larvae and general sampling. Needs a sturdy net. Allows accurate identification. Often ineffective for adult great crested newts. Long ‘season’ (March-October). Disturbance to pond. Can be carried out during the daytime. Risk of transfer of pest plants and possibly diseases.

14. Torching Newts primarily nocturnal Detects presence and allows a count Best time March-May Warm, still evenings (Avoid wind, rain, or low temperatures) Larvae detected late summer, early autumn

15.Torching Two- metre sections The torch should be moved away from the bank and back, to cover the area of the pond in the two- metre segment Repeat for all the accessible areas of the pond Record the percentage of the perimeter surveyed Daytime survey work should occur prior to torching, so that any potential hazards can be identified in the daylight

16.Torching Size difference of GCN obvious, and male tail flash Count total newts seen

17. Torching Brighter generally better. (e.g. 500,000 to 1,000,000 candlepower ) Good torch can cost £40-120 e.g. Clubman CB1 or CB2

18. Torching Advantages Disadvantages Minimal disturbance to pond and newts Has to be done after dark (safety & access issues) Quick survey method Unsuitable in rainy and windy weather Identification of species can be difficult from a distance Difficult in murky and turbid ponds (e.g. after netting)

19.Bottle (or funnel) Trapping Typically used where torching is not possible Turbid water, too much vegetation, rain, wind More onerous and potentially dangerous than torching, netting etc.

20. Bottle Trapping – Welfare Issues March-April: 12 hours May: 10 hours June: 8 hours July-August: 7 hours Sept- October: 8 hours

21.Bottle Trapping Advantages Disadvantages Reliable method to detect adults and larvae Risk of killing adults and larvae (and other species) Useful technique in weedy or turbid ponds Risk of vandalism/interference Allows accurate identification Logistically onerous – You MUST be trained and experienced to use bottle trapping! Keeps pond disturbance to a minimum Stakes can puncture pond liners

22.Refuge searching Looking under rocks, logs, discarded debris – where moisture is retained March-October A bit hit and miss Supplementary technique only

23.Method J F M A M J J A S O N D Bottle + ☻ ☻ ☻ + + ☻ L ☻ L Egg + ☻ ☻ ☻ + Torch + ☻ ☻ ☻ + + +L +L Net + ☻ ☻ ☻ + + ☻ L +L Pitfall + ☻ ☻ ☻ + + + ☻ + Refuge + ☻ ☻ ☻ ☻ ☻ ☻ + + = may be found/ less effective ☻ = optimal/ most effective L = larvae present Fdsfgdgggdg

24.NARRS – pond selection A NARRS amphibian survey is conducted on a pond in a randomly-chosen square, usually within 5 km of the surveyor’s post code Important to have representative sample Home

25.Locating the pond within your square Starting at the south-west corner of the square, find the nearest pond Can locate on map, but need to confirm in the field

26.Gaining access permission Unless there are public rights of way, you must get permission from the landowner to visit the site and carry out the survey. You need to check that your mapped pond is still present, and that there are no other ponds closer to the south-west corner of the square. Knock on doors and ask locally Use access request letter (see www.narrs.org.uk)

27.Pond access If there are no ponds within the survey square then move to one of the immediately neighbouring squares – start with the square to the north, then move clockwise If a landowner is unwilling to grant permission for you to access the site, either move to a neighbouring square as above or request another square from ARC

28.Definition of ‘pond’ Water body between one square metre and two hectares, which holds water for at least four months of the year

29.How to carry out the pond survey Your contact with the landowner is a good opportunity to find out some information about the pond, for example: Has it been stocked with fish? How often does it dry out? Are there any safety issues, e.g. steep or slippery banks? Is it known to support amphibians? !Remember to prepare your risk assessment!