Talaud black birdwing (Troides dohertyi)

Kingdom	Animalia
Phylum	Arthropoda
Class	Insecta
Order	Lepidoptera
Family	Papilionidae
Genus	Troides (1)

Classified as Vulnerable (VU) on the IUCN Red List (1) and listed on Appendix II of CITES (2).

As its common name suggests, the male of this large tropical butterfly is almost entirely black on its upperside, and as such, is the darkest of all Troides birdwings (3). The underside of the hindwing does, however, bear the golden markings typical of Troides species, and a very few males have faint suggestions of gold colouration on the upper surface of their hindwing, but this is rare. Females have a restricted area of yellow markings on their hindwings, and obscure whitish to tan stripes on their forewings (4). The Talaud black birdwing is regarded by some as a subspecies of Troides rhadamanthus, but is separated by others on the basis of adult colour difference (5).

Confined to the islands of Talaud and the nearby island of Sangihe, Indonesia, between Sulawesi and the Philippines (6).

Inhabits lowland forest and coastal areas (3) (7).

Little has been documented on the biology of this species, but there are certain biological characteristics known to be common to most, if not all, birdwing butterflies. The adults of all Troides species feed on the nectar of flowers, and the larvae on the leaves of Aristolochia and Pararistolochia plants (both in the family Aristolochiaceae) (8). The eggs are normally laid on these plants, and once the caterpillars hatch, they voraciously munch through the leaves around them. Feeding upon these plants also serves as a defensive mechanism, as they contain certain chemicals that make the caterpillars toxic and therefore unpalatable to most predators (9). The caterpillars eventually pupate and undergo metamorphosis into adult butterflies, and may even manage to maintain this toxic acid in their tissues into adulthood (9). Troides birdwings typically pupate on the twigs or stems of plants close to the larval food plant or on the food plant itself (4).

The principal threats to Troides butterflies are increasing human populations and deforestation. Over-collection from the wild for the international market may also have some impact (8). Although still relatively common (6), the Talaud black birdwing is threatened by the large human population in its coastal range (3). The islands are still volcanically active and most of the human ‘development’ therefore takes place in the coastal regions where this butterfly lives (3).

Its listing on Appendix II of the Convention on International Trade in Endangered Species (CITES) helps protect this butterfly from excessive trade to international collectors (2), and therefore over-collection from the wild. There are a couple of reserves within the Talaud black birdwing’s range, but these are actually hunting reserves rather than true nature or wildlife reserves. Nevertheless, they may provide some protection to this butterfly by preserving crucial areas of habitat that are protected from logging or other land development (3).

Authenticated (05/08/08) by John Tennent, Scientific Associate, Department of Entomology, The Natural History Museum, London.

• Larvae: stage in an animal’s lifecycle after it hatches from the egg. Larvae are typically very different in appearance to adults; they are able to feed and move around but usually are unable to reproduce.
• Metamorphosis: an abrupt physical change from the larval to the adult form.
• Pupate: the process of becoming a pupa, the stage of an insect’s development, when huge changes occur that reorganise the larval form into the adult form. In butterflies the pupa is also called a chrysalis.
• Subspecies: a population usually restricted to a geographical area that differs from other populations of the same species, but not to the extent of being classified as a separate species.

1. IUCN Red List (May, 2008)
   http://www.iucnredlist.org
2. CITES (July, 2006)
   http://www.cites.org
3. The World of Birdwing Butterflies (July, 2006)
   http://www.nagypal.net/ttdohert.htm
4. Haugum, J. and Low, A.M. (1985) A Monograph of the Birdwing Butterflies. Scandinavian Science Press, Klampenborg.
5. Operation Wallacea (July, 2006)
   http://www.opwall.com/Library/Indonesia/terrestrial%20inverts.shtml
6. Troides dohertyi (July, 2006)
   http://home.att.net/~bret71/T_dohertyi.htm
7. Tennent, J. (2008) Pers. comm.
8. Yen, S.H. and Yang, P.S. (2001) Illustrated Identification Guide to Insects Protected by the CITES and Wildlife Conservation Law of Taiwan. R.O.C. Council of Agriculture, Taiwan.
9. Tree of Life Web Project (July, 2006)
   http://tolweb.org/tree?group=Papilionidae&contgroup=Papilionoidea