national amphibian and reptile recording scheme – narrs amphibian surveys

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National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

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Page 1: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

National Amphibian and Reptile Recording Scheme – NARRS

Amphibian Surveys

Page 2: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

Aquatic habitat

Survey Methods

• Egg searching • Netting• Torching• Bottle trapping• Refuge searching• Pitfall trapping

Page 3: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

Egg SearchingSubmerged vegetation

Great crested newt

Smooth/palmate newt

Page 4: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys
Page 5: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys
Page 6: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys
Page 7: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

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

Page 8: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

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

Page 9: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

Netting

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

Page 10: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

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

Page 11: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

Great crested newt larva

Smooth newt larva

Page 12: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

Overwintering larva

Page 13: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

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.

Page 14: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

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

Page 15: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

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

Page 16: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

Torching

• Size difference of GCN obvious, and male tail flash

• Count total newts seen

Page 17: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

Torching

Brighter generally better. (e.g. 500,000 to 1,000,000 candlepower)

Good torch can cost £40-120e.g. Clubman CB1 or CB2

Page 18: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

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)

Page 19: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

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.

Page 20: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

Bottle Trapping – Welfare Issues

• March-April: 12 hours• May: 10 hours• June: 8 hours• July-August: 7 hours• Sept- October: 8 hours

Page 21: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

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

Page 22: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

Refuge searching

• Looking under rocks, logs, discarded debris – where moisture is retained

• March-October• A bit hit and miss• Supplementary technique only

Page 23: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

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

Page 24: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

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

Page 25: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

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

Page 26: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

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)

Page 27: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

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

Page 28: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

Definition of ‘pond’

Water body between one square metre and two hectares, which holds water for at least four months of the year

Page 29: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

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!

Page 30: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

How to carry out the pond survey

NARRS amphibian surveys are conducted using the same methods we have practiced, but note also:

Breeding frogs and toads can be detected most easily during their peak spawning time

Frog- or toadspawn can be found

Techniques used for newts can also spot frog and toad tadpoles

Page 31: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

Licensing

• Most widespread amphibians do NOT require a licence in order to carry out a survey - the exception is the great crested newt (and other EPS)

• If you are in an area where you’re likely to find GCNs, you should be licenced or accredited

• As a guide, if you find GCNs and are not licensed or accredited, you should stop surveying that pond and gain accreditation

• ARC can accredit people trained by ARC staff and/or if recommended by trusted trainers

• You must submit licence returns/results.

Page 32: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

Filling in the Survey Form

The survey form has been kept as simple as possible – while allowing key information to be recorded

Most information requested is self-explanatory e.g.

• Pond details

• Your details

• Landowner details

Page 33: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

Habitat suitability factors

Developed for the Habitat Suitability Index (HSI) for the great crested newt….

- the NARRS survey form contains space to record a simplified version of the HSI (see separate presentation).

Page 34: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

For each survey technique, record numbers of amphibians seen (indicate presence only for larvae and newt eggs).

  Visual search

  Adu Imm Larva Egg

Common frog  1  0    

Common toad        

Great crested newt        

Palmate newt         ?

Smooth newt       ?

Other species  Crassula grass snake

   

Eggs of smaller newt species are not identifiable to species – so indicate with question mark if not sure which one you have

Page 35: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

Survey conditionsThere are boxes to record the conditions under which the survey was conducted

Date  

Time : to :

Air temperature oC  

Water temperature oC  

Water clarity (score 1-3)  

Rain (score 0, 1, 2, 3)  

Wind disturbing water (tick)  

Bright moonlight (tick)

% Shoreline surveyed %

Number of traps used

(IF APPROPRIATE/LICENSED ONLY!)

Scoring for water clarity and rain given on survey form.

Page 36: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

How many times to visit the pond?

Ideally, four survey visits – but in practice, as many as a surveyor can make, up to four

The survey form provides space to record information from up to four survey visits and the method/s used at each visit

When to survey the pond?

Ideally, an early survey in March and the rest mid-April to May (but later is still OK)

Page 37: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

REMEMBER – your results are valuable and important to us however many methods you use or survey visits you are able to make!

Even NEGATIVE results (i.e. where you don’t find any species) are important!

Page 38: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

www.narrs.org.uk

Page 39: National Amphibian and Reptile Recording Scheme – NARRS Amphibian Surveys

Photographs

• Photographs used in this presentation are by Fred Holmes, Phyl King, Will Watson, Steve Bolwell, Ben Driver and John Robinson

• 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.