SURVEY METHODS & TRANSLOCATIONS
 
What is a translocation exercise?
     
A translocation exercise is the process of moving a population of animals from one habitat to another. Reptile and great crested newt translocations are usually undertaken prior to a change in land use that would render their existing habitat unsuitable.
 
The new habitat into which translocated animals are released is called a receptor site. A receptor site may be an adjoining area of land or sometimes it may be some distance away. Ideally it is a protected area, such as a nature reserve that is specifically managed for wildlife.
 
Surveying for reptiles  
   
Reptiles are cold blooded and consequently surveys can only be undertaken in periods of fine weather during the animals' active season. Generally this is between March and October although reptiles can be active outside these months if weather conditions are favourable.

The use of artificial refugia is the most efficient and commonly adopted method for locating reptiles. All reptiles have a tendency to hide under certain materials that warm up when they are exposed to the sun and the use of artificial refugia exploits this tendency. By hiding under refugia reptiles can regulate their body temperature and evade predators at the same time.

A typical survey consists of placing refugia, in the form of corrugated tins or roofing felt, in areas of suitable reptile habitat. Refugia are generally left for 2-3 weeks to 'bed in' and are then inspected for reptiles during periods of suitable weather. Any reptiles utilising the refugia can be recorded.
This unmanaged grassland in Kent is ideal reptile habitat. Over two thousand slow-worms and common lizards were removed prior to the sites development
   
Standard reptile survey methodology adopted by the statutory conservation agencies requires five visits during fine weather to inspect artificial refugia. Five visits will allow an assessment of the size of any reptile population that may be present and should ensure that all species present are identified. If reptiles are present survey results are used to form a mitigation strategy in consultation with the statutory conservation agencies. It is at this stage that reptiles can be caught for translocation.
   
Capturing reptiles for translocation  
   
Reptiles are caught by hand from under refugia during favourable weather conditions. This is a skilled operation as most species, particularly common lizards, are extremely fast and agile when fully warmed and they can be easily injured if handled incorrectly. Other methods that can be adopted alongside the use of artificial refugia include pitfall traps, drift fencing and noosing. Because they are venomous special experience is required when capturing adders.
   
In some translocation exercises slow clearance of the available reptile habitat can be undertaken. This type of habitat manipulation pushes reptiles into smaller localised areas of the translocation site and increases catch rates. It can also be used to push reptiles into areas that are not going to be developed. Reptile fencing is often used to prevent reptiles re-colonising translocation sites from surrounding habitats. Reptile fencing is normally made from thick polythene and is approximately 60cm in height. It is also buried into the ground to prevent reptiles from moving under the fence.

Development can proceed once there has been a significant decline in daily capture rates, which demonstrates that the majority of the reptile population has been removed. When an intensive trapping exercise is undertaken small sites can often be cleared of reptiles in 3-4 weeks but large sites supporting a moderate reptile population can take many weeks of daily trapping to capture the majority of the reptile population.
   
Once capture rates have dropped significantly a destructive search is usually undertaken. This involves slowly clearing the topsoil and vegetation of the site under the watching eye of a consultant ecologist.
   
Occasionally it is necessary to hold reptiles in thermostatically controlled vivariums prior to release at a receptor site. This may be because of adverse weather conditions or because the receptor site is not ready to receive the animals. Slow-worms can be fed on the small white slugs Deroceras reticulatum that are easily found under rocks and logs in hedgerows and gardens throughout Britain. Common lizards are best fed on small house crickets Acheta domesticus  or similar species that are available from pet shops and commercial breeders. Reptiles captured late in the year can also be put into hibernation in vivariums specifically designed for this purpose and released into the receptor site the following spring. Herpetosurveys have successfully bred both common lizard and slow-worm whilst holding them in preparation for release at a newly created habitat.
Undertaking a destructive search
Surveying for great crested newts  
   
The great crested newt survey season begins in March and ends in August although adult newts and larvae are often present in breeding pools outside these months. Surveys usually concentrate on potential breeding ponds (as opposed to terrestrial habitat) and utilise four main survey methods. The simplest survey method is night-time torch counts during the breeding season. Another method that is usually undertaken alongside torch counts is trapping and this is particularly important when extensive vegetation and poor water clarity prevents adequate survey by torchlight. Trapping newts is time consuming and requires skill if injury to newts is to be avoided and because of this a licence is required to undertake trapping surveys. Other survey methods include egg searches and dip-netting.
   
Occasionally it may be necessary to establish the presence or absence of great crested newts in terrestrial habitats and in these instances other survey methods need to be employed. Searching potential refuges such as under stones, logs and rubbish can often reveal large numbers of great crested newts if there is plenty of material to look under. However, in sites that lack easily investigated natural refugia it is virtually impossible to find great crested newts in their terrestrial phase even if they are present in good numbers. In these instances artificial refugia can be used in a similar way to reptile surveys. Pitfall trapping is another alternative and is usually able to identify the presence of great crested newts although it is very time consuming and also requires a licence.
   
Standard great crested newt survey methodology adopted by the statutory conservation agencies requires six visits to ponds during the breeding season. Six visits will allow an assessment of the size of any great crested newt population that may be present and should ensure that even small populations are identified. If great crested newts are present survey results are used to form a mitigation strategy in consultation with the statutory conservation agencies. It is at this stage that an application for a licence to move great crested newts is made to DEFRA. Upon receipt of a licence great crested newts can be caught for translocation.
   
Capturing great crested newts for translocation
   
Unlike reptiles, great crested newts are slow and ponderous on land and are easy to catch if encountered. In marked contrast, however, they are very fast and agile swimmers and are difficult to catch in their breeding ponds without the use of traps.
   
Great crested newt translocation exercises usually employ the use of aquatic traps, terrestrial pitfall traps, sweep netting of pond vegetation, and searches of natural and artificial refugia. It is also a common practice to use drift fencing to control movements of newts and increase capture rates. Drift fencing is made from thick polythene or plastic sheets that are buried into the ground to prevent newts from moving under the fence. Drift fences can be used to surround a breeding pond and pitfall traps placed around the base of the fence can be used to catch newts going to or leaving the pond. In an ideal situation newts are captured early in the breeding season prior to, or in the early stages, of egg laying. Great crested newt translocations can be a time consuming process and may take the entire length of the breeding season.
   
Reptile & great crested newt receptor sites  
   
The selection of receptor sites is often the most difficult part of a translocation exercise, particularly if large numbers of animals are involved. Receptor sites should:
   
be of a suitable size for the number of animals to be translocated.
provide ideal habitat for the species being translocated.
be safe in the foreseeable future from changes in land use such as development and agriculture.
ideally hold some form of protected status, such as a statutory protected nature reserve.

In the southern parts of Britain it is often extremely difficult to find suitable receptor sites for reptiles such as slow-worm and common lizard because suitable sites usually already have a resident population. However, artificial sites that have developed suitable habitat but have yet to be colonised by reptiles can be ideal. Typical sites include restored quarry workings, habitat restoration projects and rough grasslands and embankments associated with the creation of new roads and railway lines.
Releasing slow-worms and common lizards in a restored quarry that is being managed as a nature reserve
   
All potential receptor sites need to be surveyed in detail to identify the size and extent of any existing reptile or great crested newt population that may be present. In some cases receptor sites can be enhanced by creating features such as great crested newt breeding ponds, reptile hibernacula and basking banks. Future monitoring of a receptor site is often a requirement written into planning conditions in order to establish if the translocation has been successful. Receptor sites are usually located and selected in close consultation with the statutory nature conservation organisation and local wildlife groups and herpetological groups.
Digging a new great crested newt breeding pond as part of a mitigation strategy
   
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