When are reptiles active ?

Reptiles, such as adders, grass snakes, common lizards and slow worms, rely on the heat from the sun to warm their bodies in order to become active, but if it becomes too hot will overheat and seek shelter from the midday sun.

Therefore, these creatures are only active during the warmer months, typically from March to October, but are easiest to spot when the weather is not above about 18 degrees C [ so June and July are often too hot once the sun is fully up]. During suitable times, they can sometimes be seen basking in the sun on south-facing banks, or rocks, or underneath hotspots, such as discarded corrugated iron sheets. They hibernate throughout the colder, winter months, during which time they seek refuge underground or, for example, in log or rubble piles, so called “hibernaculum”.

NWS can undertake reptile surveys on sites, that are proposed to be developed. Where they are discovered on a site, we can advise clients on any mitigation required, for example reptile translocations or habitat creation.

Bat survey – what does it involve ?

Why and when is a survey needed ?

All British species of bats and their roosts are protected by UK and European law.  Local Planning Authorities (LPA) therefore take bats into account when determining planning applications and may request a bat survey.

Bat survey of barn with an endoscope by Stewart

Bat survey of barn with an endoscope by Stewart

A bat survey is required where bats could be affected by a development. Examples include sites such as old barns, buildings close to woodland and water, bridges, and old trees. The presence of bats does not mean that the development cannot go ahead. It just means that more details may be required on their use of the site.

Anyone planning to develop or demolish a building, which might affect bats, should plan for bat surveys and perhaps any mitigation needed.  The bat survey and assessment work will require an experienced, specialist bat consultant, so you need to find someone you can work with and trust.

How is a bat survey carried out ?

The initial stage of a bat survey involves a day time visit. This allows advice on the likelihood of bats being present or using the site.  If bats are potentially present, then summer bat “emergence surveys”, carried out at dawn and dusk, can then tell if the building is used as a roost. This also builds up detail about how any bats are using the site and the wider landscape. Sometimes winter bat surveys are required where there are cellars or suitable places for hibernation (e.g. ice houses ), but this are rare in East Anglia.

A similar method will apply for tree survey, although for woodlands a tree assessment method or transects may be more appropriate.

How is it used ?

The bat survey will be used by the planning authority to determine the application, and this may include attaching conditions such as timing for the development, installing a bat loft or bat boxes. Landscaping works may enhance the habitat for bats around the development.

What happens after planning ?

Where bats are significantly affected then a European Protected Species (EPS) licence will be required from Natural England.  This is issued free, but needs a bat specialist to put together the application and supervise the works. The licence set out how the works must be carried out as well as any monitoring after the development is completed.  Once this is in place the works can proceed on a clear timetable.

Our tip for when planning a development is to seek initial advice for your bat survey and mitigation well in advance to prevents unexpected delays in planning.

Further info

The Bat Conservation Trust has recently published good practice guidelines on the process for bat surveys and mitigation. These are a very helpful guide where bats are affected by development proposals.

Pee of newt and poo of bat – bat identification from droppings and DNA

Droppings, faeces, dung, poo – call it what you will these are a mainstay in the ecologists fieldcraft for id’ing species, and bats are no different.

Finding bat droppings within barns and lofts, at bat access points and under cracks and holes in trees is a good initial indicator of bat presence at a site. Knowing they are bat droppings is relatively easy, as although they look very similar to mouse droppings, when crushed they easily break down to a fine powder, made of insect carapaces.

You can sometimes determine the species or group of bat species present, purely from their droppings. Until recently this has been fairly tough, relying predominantly on how the droppings look….their colour, size, shape and texture.

Pipistrelle droppings are usually very small and regularly oval shaped, but by eye you can’t tell the difference in droppings between the three different species. Brown long-eared bat droppings are usually longer and twisted, but can often break up at the twists to look like smaller droppings. Serotine droppings are usually ‘bullet’ shaped.

However, there can be substantial differences between droppings from individual bats of the same species, with the diet playing the greatest role.

Brave souls have endeavoured to determine bat species by dissecting bat droppings using a microscope, and using the insect fragments that remain to determine what the bat’s diet is. This can then be compared to databases on preferred prey of different species. A taxing and time consuming process.

But more recently, DNA analysis technology has made identification of bat species from their droppings quick, easy and reliable. Specialist labs extract DNA from a single bat dropping (to avoid any risk of cross species contamination), undertake Polymerase Chain Reaction (PCR) to obtain the mitochondrial DNA sequence, allowing identification to species through phylogenetic analysis [ apparently !]. And, as there is no overlap in mitochondrial DNA between species.

In plain English, an almost 100% reliable way of id’ing bats by their poo !

No one squashed in destructive search

During the start of the year, Norfolk Wildlife Services had a busy couple of days, when we were asked to assist at very short notice with an emergency destructive search of a small grass field outside of Norwich, where there was concern about the presence of protected species, but emergency public water supply works were also required.

Working together Abi and Stewart and the JCB drivers used an approved method statement that protected the wildlife, but also kept the ecologists out of risk of injury from being squashed.  So it could be done safety but efficiently, the digger drivers slowly removed grassy vegetation and the top soil, then the ecologists checked closely to find and move any wildlife out of harm’s way, each taking it in turn from the other. Luckily the find was limited to three hairy caterpillar and the site was declared clear for the client to start construction on site the same day.


What are your top tips for a successful project?

  1. Be able to recognise when there might be an issue – protected species, timings of surveys, delays to your project, etc.
  2. Know when to seek professional help – problems from wildlife generally arise when surveys are sought too late, i.e. after plans have been drawn up or builders engaged.
  3. When in doubt, seek an opinion as soon as possible – bring in an expert to ‘eyeball’ your site early on so that you don’t get caught out when it’s too late.
  4. Allow for timings for wildlife surveys and mitigation in your timetable – generally these will be undertaken in the summer months, so plan ahead and make sure you get these scheduled in in good time.
  5. Much of the protection for wildlife is under criminal law and many offences are arrestable, so take it seriously!

What information is needed for a survey?

A site location plan (“red line” plan) will always be required. Also useful are proposals for the finished development, any pre-existing ecology surveys that have been undertaken at the site, a timetable for your project with clear deadlines and details of any effects, e.g. drainage, hydrology, lighting, transport access and construction methods.

What do surveys entail?

Preliminary surveys (Phase 1, Ecology surveys, etc) will start with an ecological walkover of the entire site, where access is available, to look at the mix of habitats and assess which follow-up surveys will be required. Where newt and bat surveys are suggested, this will include nocturnal visits to the site and require dusk-to-dawn access for our surveyors. Occasionally, the use of monitoring equipment, such as Anabat recorders, is required and these must sometimes be left on site for a period of time.

What happens if I don’t carry out a survey?

Not carrying out the required ecological surveys could have serious implications for you and your project. If applying for planning permission, this could be refused or severely delayed whilst the council wait for you to supply them with the required ecological reports. In extreme cases, you could be held responsible for criminal issues under reckless behaviour and face criminal prosecution, fines and even prison sentences.