Apollo Butterfly

Adult Apollo butterflies are seen on the wing in mid-summer (2), feeding on nectar produced by flowers (8). The females lay eggs, which over-winter and hatch in spring the following year (5) (6). The resulting caterpillars feed on stonecrop (Sedum species) and houseleek (Sempervivum species) (4). When the caterpillar is fully-grown it will pupate on the ground, forming a loose cocoon from which the adult butterfly emerges following metamorphosis (2).

Laws exist to protect the Apollo butterfly in many countries, and it is also listed on Appendix II on the Convention on International Trade in Endangered Species (CITES), which restricts trade in this species (3) (5). However, these laws focus on the protection of individuals, rather than their habitat, and so may do little to mitigate the greatest threat that populations face (5). Fortunately, there are a number of projects specifically working to save this Vulnerable insect. A conservation programme in Pieniny National Park saved a subspecies of the Apollo butterfly that had declined to just 20 individuals in the early 1990s, through a combination of captive breeding and habitat protection (9). In south-west Germany, conservationists are working with shepherds to ensure favourable conditions for the butterfly, which share their grassland habitat with sheep. For example, grazing periods have been shifted to avoid the Apollo butterfly larvae stage, which is vulnerable to being trampled (10). With the continuation of these tremendous efforts, there is hope for this beautiful butterfly.

The Apollo is a beautiful white butterfly, decorated with large black spots on the forewings and red eye-spots on the hindwings (4). These striking red eye-spots can vary in size and form depending on where the butterfly comes from, and the bright red colour often fades in the sun, causing the eye-spots of older individuals to appear more orange (5) (6). The wings are shiny, with slightly transparent edges (2), and some individuals are darker (melanistic); a general phenomenon common in many butterflies (6). The caterpillars are velvety black with orange-red spots along the sides (4). As well as being a great deal of individual variation in the appearance of the Apollo butterfly, a number of subspecies have also been described (7).

The Apollo butterfly inhabits mountain meadows and pastures, up to 2,000 metres above sea level (2), where there are plenty of nectar-providing flowers. Apollo caterpillars require stonecrop (Sedum species) and houseleek plants (Sempervivum species) which grow on barren rocky outcrops or gravel. Research has shown that it is vital for this species that the rocky outcrops, (with stonecrops and houseleek plants), are situated in close proximity to meadows and other nectar-rich areas (8).

Found throughout Europe, including Fennoscandia, into central Asia (4).

Classified as Vulnerable (VU) on the IUCN Red List 2007 (1), and listed on Appendix II of CITES (3).

The beautiful Apollo butterfly has long been prized by collectors, who aim to possess as many of the variants as possible. While over-collecting is believed to have caused populations to decline in some areas, such as in Spain and Italy, habitat change is thought to be a far more significant threat to this species' survival (5). Plantations of conifers, the succession of suitable habitat to scrubland, agriculture, and urbanization have all reduced the habitat of the Apollo butterfly. Climate change and acid rain have also been implicated in this species decline in Fennoscandia. In addition, motor vehicles have been cited as a cause of Apollo butterfly mortalities; vehicles on a motorway system near Bozen in South Tyrol, Italy, are said to have nearly wiped out a race of the Apollo (5).