Covid restrictions have twice postponed the final year of the Hertfordshire Mammal, Amphibian and Reptile Atlas (Herts MARA) project. But it's been full steam ahead in 2022, with a strong  focus on under-recorded parts of the county during the closing months.

The survey aims to achieve the best possible, countywide coverage for six amphibian, three reptile, 32 mammal and 12 bat species found in our county.  The MARA team have now received records for at least one species for almost all the tetrads (2km squares) that are more than a quarter within Hertfordshire's boundaries. This indicates that some recording has happened pretty much everywhere.

By Jan 2022, 4,300 verified records had been submitted to the HNHS website record page and the distribution maps can be viewed on the Mammals atlas pages which are updated every six months. Additional records submitted to iRecord are also being verified by Chantal Helm and Jenny Jones and will be added to the final distribution maps, along with any records obtained from other recording schemes.

A preliminary gap analysis exercise was undertaken at the start of 2022 to identify the gaps across the county to focus survey effort. The figures below show a red green blue colour coded map of tetrads showing records collected between 2000 and 2021 for selected species.

Red indicates those tetrads where records were obtained for a species between 2000 and 2014, but no record has been obtained since 2015 when the Atlas project started. For these species, it is the red tetrads that we should be focussing on to fill the remaining gaps in the dataset for the rest of 2022. The blue tetrads indicate that we have records for both the pre 2015 and post 2015 periods and green tetrads are those where we only have records from 2015 onwards. 

Renewed thanks  go to everyone who has submitted records to date with a a plea to continue sending them in. Another way to focus on the gaps is to view the preliminary distribution maps on the Herts MARA Atlas pages 

Hedgehog photograph © Gary Mason


Hedgehog                                                                      Rabbit



Badger                                                    Fallow Deer



Polecat                                                                 Brown Hare