A conservation milestone: Apollo successfully reintroduced in Austria’s first two habitats

European Wilderness Society is one of the partners to LIFE Apollo2020 project and we are glad to share exciting news about the project!

We are thrilled to announce that the LIFE Apollo2020 project has achieved a significant milestone: the successful reintroduction of the Apollo (Parnassius apollo) into two key habitats in Austria—Leisach in Tyrol and Rheindamm in Vorarlberg. Carried out between 2023 and 2024 as part of Action C3.3: Reintroduction in the Austrian Alps, these efforts are a cornerstone of the project’s mission to restore this iconic species to its natural environment. This success was driven by dedicated teamwork of Austrian partner and the invaluable expertise of the Saalfelden breeding farm, led by Otto Feldner. His extensive experience in breeding and reintroduction played a crucial role in achieving this goal. Together, careful planning and collaboration have shown how conservation efforts can reverse biodiversity loss and bring endangered species back to thriving habitats.

Leisach: A jewel of the Tyrolean Alps along the railway

The Leisach habitat, located in Tyrol, is characterised by rocky, sunlit terrain with steep slopes, frequent rockfalls, and nutrient-poor soils. These xerothermic conditions make it ideal for Parnassius apollo. However, prior to the project, the species had disappeared from the area.

Habitat restoration and critical preparatory actions were crucial to enable the successful reintroduction of the Apollo in Leisach. One major challenge for the successful reintroduction of Apollo was the glyphosate use along the railway track that crosses the habitat. However, through the dedicated lobbying efforts of the Austrian partner, the European Wilderness Society, the cessation of glyphosate use by ÖBB was successfully achieved in 2022. This precaution was essential to protect the Apollo’s food sources and ensure a safe environment for reintroduction. Another crucial step was the planting of over 500 Sedum plants, such as Sedum album and Sedum maximum, to provide a sufficient feeding base for the reintroduced caterpillars.

Reintroduction efforts began in 2023 with the release of 40 Apollo caterpillars, marking the start of the species’ return to Leisach. In 2024, these efforts expanded with the release of 100 more caterpillars and additional Sedum planting (S. album, S. maximum, and S. sexangulare). Monitoring has shown promising results, with a thriving population of caterpillars and imagos confirming the habitat’s suitability for the Apollo. Despite human and natural challenges, the careful planning and implementation of restoration measures have ensured the long-term potential of this remarkable site.

Rheindamm: A restored haven along the river Rhine

The Rheindamm habitat in Vorarlberg is situated along a man-made flood control dam, stretching alongside the Rhine River. The dam, constructed to protect surrounding communities from flooding, is characterised by rocky, south-facing slopes and nutrient-poor soils, creating ideal conditions for Parnassius apollo. However, being part of the Natura 2000 conservation area, all restoration actions required close collaboration and trust-building with local authorities. These efforts ensured that conservation measures were implemented with full agreement and alignment with existing priorities.

As in Leisach, the planting of Sedum species (S. album, S. sexangulare, S. sempervivum) was essential to secure a sufficient food supply for Apollo caterpillars. Over 700 Sedum plants were planted between 2022 and 2024, transforming the habitat into a thriving ecosystem for Apollo.

The reintroduction began in 2023 with the release of 300 eggs and 80 caterpillars, followed in 2024 by the addition of 250 eggs and 150 caterpillars. Reintroducing Apollo eggs is a delicate task that requires manual precision and patience. The eggs, which are really tiny, must be carefully placed either on the finger or with a fine brush to avoid any damage or unwanted loss. It is also important to position the eggs close to feeding plants, such as Sedum, Sempervivum, and Rhodiola species, to ensure that newly hatched larvae can immediately access a suitable food source.

The success at Rheindamm highlights the importance of long-term planning and collaboration with local stakeholders, ensuring the habitat remains a safe haven for Parnassius apollo.

Securing the Apollo’s future

The establishment of thriving Apollo populations in Leisach and Rheindamm represents a significant milestone, but it is only the beginning. The ultimate goal of the LIFE Apollo2020 project in Austria is to establish self sustaining Apollo populations at all project sites, ensuring the species’ long-term survival across its historical range.

In order to achieve this vision, the European Wilderness Society, in collaboration with the experienced breeder Otto Feldner, is making continuous and dedicated efforts to expand these successes to other reintroduction sites. Their work involves breeding high-quality individuals at the Saalfelden breeding farm, improving habitat conditions, and gradually reintroducing more Apollo butterflies to additional locations.

Future actions will include:

• Ongoing monitoring of populations and habitats to ensure long-term success.
• Continued Sedum planting and nectar planting to secure a robust food supply for Apollo caterpillars (larvae) and adult butterflies (imagines).
• Strengthening collaborations with landowners and authorities to protect existing and new reintroduction sites.
• Selective shrub removal to open up habitats, whether for new reintroduction efforts or for existing populations that require support to thrive.
• Arranging insect-friendly mowing and grazing practices, in coordination with landowners and authorities, whenever possible and agreeable.

By combining expert and decades of knowledge, habitat restoration, and collaborative partnerships, the project is setting the stage for self-sustaining Apollo populations across Austria. These efforts also contribute to the wider conservation of biodiversity and the ecological resilience of these regions. The Apollo’s return to these landscapes is a powerful symbol of resilience and hope, showcasing how dedicated conservation efforts can reverse biodiversity loss and restore iconic species to their rightful habitats.