Wallace’s golden birdwing butterfly  (Ornithoptera croesus)

Classified as Endangered (EN) on the IUCN Red List (1) and listed on Appendix II of CITES (3).

Named in affectionate honour of renowned British naturalist Alfred Russel Wallace, who discovered the species in 1859, Wallace’s golden birdwing butterfly is an insect of indescribable ‘beauty and brilliancy’(4). The male butterfly is perhaps the most glorious of the sexes, with black forewings with a gold, orange or red leading edge, and golden yellow hindwings with black veins and edges. The undersides of the wings are iridscent green, with black edges and veins (2) (5). The head and thorax are black and the abdomen is yellow (5). The wings of the female, the larger of the sexes, are dark brown on both the upperside and underside with occasional yellowish-grey spots (2) (5), and the head and thorax are brown rather than black (5). The appearance of the caterpillar of this species is not well documented but is likely to be brown with several rows of dark spines (6).

Wallace’s golden birdwing butterfly occurs only in the Maluku Islands, Indonesia (also known as the Moluccan Islands) (4).

This butterfly occurs in wet lowland environments such as swamps (6)

The female Wallace’s golden birdwing butterflylays its eggs on the leaves of a plant, most commonly a Pararistolochia species. When the caterpillar hatches, it will proceed to eat the plant’s leaves until it has grown enough to pupate, which is usually does on the stem of the plant. After several weeks, the adult butterfly will emerge. It has been noted that the adult butterfly feeds predominantly on Mussaenda, a shrub plant with yellow flowers (4)

The rampant, unsustainable logging that has taken place in the lowland areas of the Maluku Islands has significantly reduced the forest coverageand has no doubt reduced numbers of Wallace’s golden birdwing butterfly (4). Large-scale, commercial deforestation continues to pose a considerable threat to the future of Wallace’s golden birdwing butterfly and other inhabitants of these biodiverse forests (4). In addition, the extreme use of insecticides to combat mosquitoes may be having a detrimental effect on Wallace’s golden birdwing butterfly, although the impact of this has not yet been assessed (4).

While there are currently no known specific conservation measures in place for Wallace’s golden birdwing butterfly, a number of conservation organisations are working to conserve wildlife in this region of Indonesia.

View information on this species at the UNEP World Conservation Monitoring Centre.

To find out more about wildlife conservation in Indonesia see:

• Conservation International:
  http://www.biodiversityhotspots.org/xp/Hotspots/wallacea
• WWF:
  http://wwf.panda.org/about_our_earth/ecoregions/molucass_moist_forests.cfm