Butterfly Conservation maintains and manages large national datasets of butterfly and moth species records, as well as being a partner in the UK Butterfly Monitoring Scheme. These data are the bedrock of our research work but also play a significant role as the evidence base of our policy work. Two recent examples are our input into the Joint Nature Conservation Committee (JNCC) led Quinquennial review of species listed for protection under the Wildlife and Countryside Act. For this we used the population trends calculated and published in two recent red list reviews of British Lepidoptera (Fox, Parsons and Harrower (2019) for the moths and Fox and Dennis (in prep) for the butterflies; both are currently unpublished reports to Natural England).

For moths we have recommended that seven species retain their listing in Schedule 5 (fully protected) and one species is removed (it has not been recorded in the UK for over 40 years). A further 27 moths meet the criteria but we are not recommending them to be added to the Schedule, either because we have no evidence of threat (21 species) or because there is no evidence of threat and they are widespread (6 species). Listing them risks criminalising the recording of moths in gardens and the wider countryside, with no conservation gain.

For butterflies, five species have been recommended to remain fully protected under Schedule 5, while one species no longer qualifies (again it has been extinct in the wild for over 50 years) and one species is recommended to have its level of protection increased from partial to full. Four species while meeting the criteria for full protection should retain their current (slightly lower) level, while a further two species meet the criteria due to their decline rate but are not recommended for listing as we do not think this will aid the conservation of these widespread species. More worryingly, 14 species that are currently partially protected under the Wildlife and Countryside Act do not meet the proposed new qualifying standard for listing under Schedule 5. In these cases we have presented evidence that they remain at risk and that removing their legal protection would endanger the conservation of the species concerned.

Butterfly Conservation has been a member of the Oak Processionary Moth liaison group run by Forestry England for several years. Recently a tool kit, to provide woodland owners with guidance on the implications of having Oak Processionary Moth in their woods, has been developed by the Tree Council with support from Defra and Forestry England. As part of the tool kit, an interactive risk map using our moth distribution data was incorporated. This converts the presence of moth species and their conservation importance into guidance on how best to manage the situation while minimizing the risk of harm to non-target moths. If an area is particularly rich in important moth species the tool kit steers people away from widespread spraying. The large-scale spraying of oak trees with the insecticide Bt in an attempt to reduce the occurrence of Oak Processionary Moth has concerned us for some time and we have recently produced a fact checker and updated our policy in response. In essence, we wish to see a move to living alongside the moth, managing it only when a real threat is demonstrable rather than as a matter of course. The new policy can be found here.

Nigel Bourn, Chief Scientist, Butterfly Conservation