CONSERVATION
IUCN Redlist category Data Deficient (IUCN 2020)
Rationale for redlist categorization Troides vandepolli has been assessed as Data Deficient. Although the species has a large extent of occurrence, in the past there have been reports of sharp declines in the population and local disappearance from areas where the species used to occur, especially on Java. Here it is highly likely that the nominate subspecies vandepolli is threatened, given its restricted range at high altitudes. Recent data shows that in parts of the species range in Sumatra, there has been extensive forest loss which is likely to have had an impact on this sensitive species. However, with very little data on the species' habitat, ecology and population status, it is currently impossible to make an assessment of the species, or adequately estimate its area of occupancy or extent of occurrence. Its extinction risk could range from Least Concern (where habitat loss has no or minimal impacts) to extinction risk categories which track the decline rates of habitat in the species range. More research is required to inform future reassessments of this species. (IUCN 2020)
Threat category Ecosystem conversion|Ecosystem degradation,Species mortality (IUCN 2020)
Cause of stress Intentional use (species is the target) (IUCN 2020)
Described Threats There is very little information available on current threats to the species. Haugum and Low (1983) noted that the nominate subspecies used to be numerous in the Pengalengan Plateau area, but that an increase in forest clearing for agricultural expansion had led to sharp declines and local disappearance (e.g. Roepke 1935). The species is thought to be very sensitive to habitat loss (Ruslan 2012). Forest cover loss has also been noted to occur extensively in Sumatra during the period of 2001 to now (Hansen et al. 2013); however, it is unknown to what extent this may have affected the species, especially if it has already been restricted to steep inaccessible country.
The species is listed on CITES Appendix II together with the genera Ornithoptera and Trogonoptera , with the exception of O. alexandrae which is listed on Appendix I. Recently traded individuals appear to come mostly from captive or ranched populations (CITES 2015). Butterfly ranching is generally thought of as a sound, economically viable and sustainable rural industry (Wambi 1996, Hanscom 1993, Burrows 2003 in Small 2007). However, there are concerns that butterfly ranching may not be as sustainable in some countries as it is often perceived to be (e.g., Papua New Guinea; Small 2007). This is based on a lack of data and species monitoring to assess the status of butterfly populations, and for many species, such monitoring is fraught with difficulty due to inaccessibility of their habitat (Small 2007). New and Collins (1991) noted that trade is extremely difficult to monitor because transportation of unpinned specimens is easy, especially of comparatively low value species which may instead be traded at high volumes. It has been stated that overcollecting seldom becomes a threat to butterflies, due to the reproductive capacity of insects and the difficulty in capturing significant numbers of the population (Pyle and Hughes 1978, in Parsons 1992). However, where birdwing butterflies are highly specific to host plants and where density of these host plants limits population size, collection in conjunction with habitat loss could have significant impacts on the species or subpopulations. However, at present, none of the individuals reported in the CITES database as traded between 2000 and 2015 stem from wild populations (CITES 2015). (IUCN 2020)
Commercial use Butterflies are mostly traded dead for the curio market (Collins and Morris 1985, New and Collins 1991). Between 1998 to 2007, 306,000 butterflies were traded from Southeast Asia, with 13,000 of these being wild-caught (Nijman 2010). There is a distinct shift towards ranched and captive-bred individuals in trade from 2003 onwards; in 1985, it was reported that globally less than 10% of trade was in ranched individuals (Collins and Morris 1985). Altogether at least 34 different species were recorded in trade, most of which belonged to the birdwing butterflies ( Troides and Ornithoptera ; Nijman 2010). It should be noted that trade in butterflies may be underreported, because of difficulties monitoring. New and Collins (1991) noted that trade is extremely difficult to monitor because transportation of unpinned specimens is easy, especially of comparatively low value species which may instead be traded at high volumes.
Birdwings can fetch high prices on the market. For example, butterfly collectors have paid high prices for birdwing butterflies of this genus: a pair of Ornithoptera meridionalis was reported to have fetched USD 3,400 in Germany (Melisch and Schutz 2000). Reported prices for Troides are however much lower. For example, a more recent pricing was around $85 per pair of T. hypolitus , around $15 per individual of T. helena and between $43 and $85 per pair of T. haliphron (Putri 2016). Recent data from the CITES Trade database show, that since 2000 and 2015 around 4,500 individuals were exported from Indonesia, only four of which were reported to stem from wild populations (CITES 2015). All others originate from ranched and captive populations (CITES 2015). UNEP-WCMC (2012) also reports that the vast majority of traded individuals come from ranched and captive-bred populations. (IUCN 2020)
Applied conservation actions This species is listed with all other birdwings ( Ornithoptera and Trogonoptera, with the exception of O. alexandrae which is listed on Appendix I) on CITES Appendix II. In 1991, New and Collins suggested work to fully integrate swallowtails into national conservation planning in Indonesia (1991), primarily for those species which were identified as threatened at the time - however, any such work would likely have benefited other birdwing species in the country. It is also protected nationally in Indonesia (Morris and Collins 1985). While considered uncommon, the species was not listed as threatened in 1985 (Morris and Collins 1985). It may occur in protected areas throughout its range: for example, an unidentified species closely resembling this species was observed in low numbers at Bukit Barisan Selatan National Park, Sumatra (Hasanah et al. 2006). However, this record requires verification as the species was not officially identified and the locality is further south than known records for this species on Sumatra. In addition, there is still very little information available on the habitats and ecology of this species, and research is required to address this, with a specific view to elucidate the impacts of forest loss on this species. (IUCN 2020)
REFERENCES
- CITES. 2015. CITES Trade Data Base. Available at: http://trade.cites.org/.
- Collins, N.M. and Morris, M.G. 1985. Threatened Swallowtail Butterflies of the World. The IUCN Red Data Book. IUCN, Gland and Cambridge.
- Hanscom, T. 1993. Setting hearts aflutter: little butterflies take wing as big business. The Rotarian 163: 16-19.
- Hansen, M.C., Potapov, P.V., Moore, R., Hancher, M., Turubanova, S.A., Tyukavina, A., Thau, D., Stehman, S.V., Goetz, S.J., Loveland, T.R., Kommareddy, A,. Egorov, A., Chini, L., Justice, C.O. and Townshend, J.R.G. 2013. High-resolution global maps of 21st-century forest cover change. Science 342: 850-853.
- Hasanah, N., Tabadepu, H., Sahari, B. and Buchori, D. 2006. Butterfly Community Structure in Bukit Barisan Selatan National Park, Sumatera. PEKA Indonesia & Wildlife Conservation Society.
- IUCN. 2020. The IUCN Red List of Threatened Species. Version 2020-3. Available at: www.iucnredlist.org. (Accessed: 10 December 2020).
- Melisch, R. and Schutz, P. 2000. Butterflies and beetles in Germany. Traffic Bulletin 18: 91-93.
- New, T.R. and Collins, N.M. 1991. Swallowtail butterflies: an action plan for their conservation. International Union for Conservation of Nature and Natural Resources/Species Survival Commission Lepidoptera Specialist Group, Gland, Switzerland.
- Nijman, V. 2010. An overview of international wildlife trade from Southeast Asia. Biodiversity and Conservation 19(1101-1114).
- Parsons, M.J. 1992. The butterfly farming and trading industry in the Indo-Australian region and its role in tropical forest conservation. Tropical Lepidoptera 3(Suppl. 1): 1-31.
- Putri, I.A.S.L.P. 2016. Handicraft of butterflies and moths (Insecta: Lepidoptera) in Bantimurung Nature Recreation Park and its implications on conservation. Biodiversitas 17(2): 823-831.
- Pyle, R.M. and Hughes, S.A. 1978. Conservation and Utilization of the Insect Resources of Papua New Guinea. Wildlife Branch, Department of Natural Resources, Port Moresby.
- Roepke, W. 1935. Rhopalocera Javanica (Derde Gedeelte): Geïllustreerd Overzicht der Dagvlinders van Java. H. Veenman & Zonen, Wageningen.
- Ruslan, H. 2012. Community of Superfamily Papilionoidea Butterflies at Nature Educational Conservation Centre Bodogol, Sukabumi, West Java. MSc Thesis, Bogor Agricultural University.
- Small, R.D.S. 2007. Becoming unsustainable? Recent trends in the formal sector of insect trading in Papua New Guinea. Oryx 41(3): 386-389.
- Wambi, D. 1996. Birds, bugs and butterflies. New Guinea Insight 6: 5-9.