- Somerset Badger Group – provide an advisory service as well as collecting records across the county.
- Somerset Bat Group – conduct systematic surveys, raise awareness about bats and aid their conservation.
- Somerset Otter Group – carry out regular recording in order to monitor Somerset’s otter population and aid conservation efforts.
- Exmoor Natural History Society – record and study the wildlife of the National Park and Minehead area, and carry out practical conservation work.
- Somerset Archaeological and Natural History Society (SANHS) – promote the study of archaeology, natural history and history of the historic County of Somerset.
- Somerset Environmental Records Centre (SERC) – the central repository for biological and geological information in the county.
- Somerset Wildlife Trust (SWT) – the county’s leading environmental charity.
- Bristol Naturalist’s Society – have a mammal section that collates records in the Bristol area, and arranges occasional talks and walks.
- Cornwall Mammal Group
- Devon Mammal Group
- Dorset Mammal Group
- Wiltshire Mammal Group
- Mammal Society – promote the study and conservation of all British mammals, including coordinating national surveys.
- Bat Conservation Trust – work to conserve bats and their habitats in the UK, and acts as an umbrella organisation for the network of local bat groups.
- Hare Preservation Trust – support the conservation and monitoring of brown, mountain and Irish hares.
- People’s Trust for Endangered Species (PTES) – provide support for conservationists and coordinate national surveys.
- Vincent Wildlife Trust – an independent charity engaged in research and conservation of mammals in Britain and Ireland.