Herts survey for mammals, amphibians and reptiles 2015-2019


A four-year survey is under way to compile a new atlas of Hertfordshire’s mammals, amphibians and reptiles. Friends of Bernards Heath and other residents with an interest in wildlife can make a welcome contribution to the project by submitting their sightings.

Update: 21 May 2016.
David Uttig, who leads the survey on the Heath, reports that nothing of interest has been found under the mats yet. They are located at 51 45 43N   0 19 59W and 51 45 46N   0 20 9W.  You can find out where these are by entering the co-ordinates into a Google maps search.

Update  4 June 2016
Two more mats have now been added in Beech Bottom Dyke at 51.46.6N  0.19.41W  and  51.46.11N    0.19.35W

The organisers, including representatives from the Hertfordshire Natural History Society (HNHS), the Herts and Middlesex Wildlife Trust and the University of Hertfordshire, want to map the distribution of all the relevant species, now matter how seemingly common. Records of grey squirrel, brown rat, rabbit and common frog are needed alongside those of more elusive species like weasels, grass snakes and slow worms.

Reliable observations of live animals are welcome, but so, too, are sightings of their tracks, signs and carcasses, including roadkill and those killed by domestic cats and other predators.

Small mammals, such as the different species of mouse and vole, can be confusing and difficult to identify accurately unless seen at close quarters. To help with this, survey volunteers are laying down so-called ‘passive refugia’: squares of asphalt roofing felt (or sometimes corrugated metal) that provide warm protected areas for them to shelter or even nest.


refugia mat

If you should come across one of these (marked ‘HNHS Survey’) please do not mistake it for litter. If you can discourage dogs from exploring them and resist the temptation to take a look underneath yourself, and, that will also be a real help.

The survey organisers are applying other, more intensive techniques to investigate selected areas (divided into 2x2km ‘tetrads’) that are expected to yield especially rich or valuable data. The specialist identification of bat species (almost impossible without sound recording and analysis, or trapping by licensed experts) is also taking place.

The last organised county survey started in 1970 and resulted in the publication of Michael Clark’s 2001 book Mammals, Amphibians and Reptiles of Hertfordshire. Results from the new Hertfordshire Mammals, Amphibians and Reptiles Atlas Project (MARA) will be published by HNHS in the same, attractively designed and illustrated series as Birds of Hertfordshire (2015) and Flora of Hertfordshire (2009)

More details about the atlas survey can be found on the HNHS website at http://hnhs.org/article/mammals-reptiles-and-amphibians-new-countywide-survey. This includes a list of all the species in the survey and information on how to submit records.

This can be done by using a webpage that makes it straightforward to zoom in on the location for each sighting, generating a six-figure map reference that the survey requires. However, those who prefer to send in multiple records by hand can download a purpose-designed spreadsheet.

The website also enable contributors to track progress with the survey, including records from the Bernards Heath area (look for TL10N St Albans).

David Utting

April 2016


Posted in Wildlife