Overview of the Compton Tortoiseshell Butterfly (Nymphalis vaualbum)
Nymphalis vaualbum is a striking diurnal butterfly, known in Europe and the Balkans both as a migrant species and, in some areas, as forming temporary colonies. Its life cycle is closely tied to broadleaved forests, particularly to river valleys and riparian zones dominated by willows and poplars. River systems and their banks, however, are increasingly affected by anthropogenic pressures—such as riverbed modification and embankment construction—which reduce suitable habitat and decrease the species’ chances of survival.
The species occurs across North America, Eastern Europe, and the temperate regions of Asia, extending to Japan, Sakhalin, and the Kuril Islands. While populations in the eastern part of its range remain stable, numbers in Europe have declined dramatically. In Bulgaria, the species is extremely rare and has been recorded only twice—near Sliven and Sofia several decades ago—with no subsequent confirmed observations.
Major Threats to the Species
- Degradation and loss of riparian forests and changes in hydrological regimes;
- Alterations in plant community composition;
- Urbanisation and infrastructure development;
- Wildfires.
Project Goal
The project aims to develop an Action Plan for the conservation of the Compton tortoiseshell butterfly.
The main activities include:
- Preparation and approval of a technical assignment for drafting the Action Plan.
- Collection and analysis of existing information from published sources and historical records held by the authors.
- Two years of field surveys conducted across the country, during different seasons and across various habitat types, in accordance with the species’ ecology.
- Expert meetings and consultations with stakeholders.
- Preparation of the first draft of the Action Plan.
- Public consultations with stakeholders in Sofia and Dragoman.
- Incorporation of comments and recommendations, and finalisation of the Action Plan for the conservation of the Compton tortoiseshell.
Why Is It Important?
The loss of rare habitats and the declining numbers of the species call for targeted measures to restore suitable environments for the Compton tortoiseshell butterfly. The development of an Action Plan aims to support the recovery and long-term conservation of the species and its habitats.