The ARC Rare Species Database

Amphibian and Reptile Conservation

Description

Amphibian and Reptile Conservation (ARC) holds 35 years of rare species records and has created a Rare Species Database. An increasing amount of this data is collected by volunteers, and ARC greatly values their support. The dataset currently uploaded to the NBN Atlas contains 30-35 years of rare species data plus ad-hoc records of widespread and non-native species. We advise you use the BRC dataset or contact local record centres/groups for the fullest distribution for widespread amphibian and reptile species. The ARC database uploaded to the NBN Gateway (now NBN Atlas) in January 2015 comprises the following datasets:

1) ARC rare reptile monitoring data c.1990-2012.

2) Summarised annual data from the Natterjack Site Register 1970 onwards.

3) All natterjack, sand lizard and smooth snake monitoring records.

4) Rare/exotic species records from BHS database (up to c.1984-1998).

5) Various third-party datasets are also included.

6) Various ad hoc records dating from 1900 onwards.

7) The Surrey and Amphibian & Reptile Group (SARG) reptile dataset, dating from 2007 to 2014 (www.surrey-arg.org.uk).

8) Batched Living Record amphibian and reptile records dating from 2010 to 2014 (www.LivingRecord.net).

9) Also included are negative records (e.g. refugia checked or sites/ponds visited with no results), as this helps distinguish places that have been surveyed, from those that have not been surveyed. We remind you that a spatial gap on a map can be due to a lack of recording effort, a probable absence or a real absence.

Please note that species introduction records have not been included in the dataset.

Geographic Description

ARC has complete geographical coverage for all known natterjack, sand lizard and smooth snake populations in Britain. Our widespread species coverage is not comprehensive as it largely reflects incidental recording at rare species sites. Exotic species coverage is not complete either. The NARRS project (www.narrs.org.uk) aims to fill these gaps. The dataset 'NARRS Data 2007-2013' is also available on the NBN Gateway.

Purpose

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Data quality

There are a number of records imported from third party datasets with grid reference issues to deal with, but nearly all ARC monitoring data are digitised using visual matching of locations on GIS. We do not record sightings that are unverified. A number of spurious records have been investigated and corrected since the last update in August 2012. The dataset has been checked using the NBN Record Cleaner.

Methods

Most of the data are field sightings, largely the monitoring work of ARC employees, and volunteers recording on behalf of ARC. Species survey records are collated using one of two methods: (i) using printed or 'on screen' site maps to record an approximate location of an observed species, or (ii) using a Global Positioning System (GPS) device when a species is recorded in the field to obtain a grid reference location for an observed species. It must be noted that use of species location data from the ARC Rare Species Database is reliant on the accuracy of data recording and input methodologies. Location data within the past 10 years is considered to be more accurate due to advances in GIS technology and the wider use of GPS devices. The species records within the dataset do not state which method of recording a species was used, though an estimation of record accuracy is provided. BHS data were digitised by the BHS before 1998, and imported electronically with no verification or validation by ARC. All other data is entered into our database only if we are confident of its validity.

Citation

Amphibian and Reptile Conservation Trust, 2016.

Rights

CC-BY-NC

Digitised records