CONSERVATION
IUCN Redlist category Near Threatened (IUCN 2020)
Rationale for redlist categorization Pachliopta atropos has been listed as Near Threatened. This species has a relatively small extent of occurrence of 26,500 km2, although this is likely an overestimate, given that the species is primarily reported from primary forests on the island of Palawan. Here, we take a precautionary approach and assume that the species is not distributed across all of the island, resulting in an extent of occurrence approaching 20,000 km2. This is further supported by the fact that little to no point localities exist for this species. There is evidence that forest loss is continuing on the island, e.g. for purposes of palm oil plantations. However, this island is still more intact than any other island of the Philippines, perhaps due to the fact that the forests, with their low density of dipterocarp trees, are of relatively low commercial value. More research is needed into the current population trends of the species and whether it is distributed widely across Palawan or is localised to certain parts of the island, as this will affect its area of occupancy and may call for a change in its category (a wider distribution would lead to an assessment of Least Concern; verification of its occurrence in very few areas may lead to a Vulnerable assessment). (IUCN 2020)
Threat category Species mortality,Ecosystem conversion,Ecosystem degradation (IUCN 2020)
Cause of stress Intentional use (species is the target),Shifting agriculture,Housing & urban areas,Unintentional effects: (subsistence/small scale) [harvest] (IUCN 2020)
Described Threats The main threat to this species on Palawan island is habitat loss. In 1985, Collins and Morris suggested that deforestation for upland rice production and logging is having an adverse effect on this species. However, this island is still more intact than any other island of the Philippines, perhaps due to the fact that the forests, with their low density of dipterocarp trees, are of relatively low commercial value (WWF 2018g). Despite this, data from the Global Forest Watch suggests more than 6% of Palawan's forest has been lost since 2001 (Panela 2014), and government regulations regarding logging have largely been ignored (WWF 2018g). In the south of the island, illegal logging is particularly common, and forest at Iwahig Prison and Penal farm may be threatened with encroachment (P. Widmann in litt. 2016). Also, in 2007 the first palm oil seedlings were planted on the island and harvesting commenced in 2011 over an area of around 3,500 hectares (Dimaano et al. 2014). This industry could have a huge impact on the forest coverage of the island unless it is carefully controlled. The constant population increase on the island could also be leading to increased deforestation, and therefore this also poses a threat to this species. In addition, although found in trade, it is unknown whether this has a significant impact on the species. (IUCN 2020)
Commercial use A specimen of this species was found for sale on the website 'Insects & more' for €15 (September 2018). However, more information on the extent to which it is utilised for trade is not available. (IUCN 2020)
Kind of conservation needed Resource & habitat protection,Site/area management,Sub-national level (IUCN 2020)
Applied conservation actions In a previous status assessment of the world's swallowtails, this species was considered to be Vulnerable (Collins and Morris 1985), an assessment which was reconfirmed in 1996 (Gimenez Dixon 1996). Following the status assessment in 1985, this and other Philippine species were considered a conservation priority in the subsequent swallowtail action plan (New and Collins 1991). Specifically, the authors called for provision of protected habitat for this and other important endemics (New and Collins 1991).
In 1992, a national law was passed in the Philippines called the Republic Act 7611, which aimed to establish a strategic environmental plan for the province, for example through sustainable development of natural resources and education of local people (Panela 2014). It essentially meant the Philippine government was committed to dedicating funds and time to preserving the rainforest of Palawan. Also the Centre for Sustainability worked with the Puerto Princesa city government to make Cleopatra's needle - one of the areas on the island that is richest in biodiversity - a forest reserve. In 2016, the Palawan Council for Sustainable Development declared this area a critical habitat, meaning it will receive extra protection (Fabro 2016). It is important that laws regarding logging and general deforestation in protected areas are properly enforced. Unfortunately in the Philippines it is particularly hard to prevent illegal logging as often the perpetrators will resort to violence (Malakunas 2017). A potential option for the future would be to employ the strategy of using forest patrols.More research is needed into the current population trends of this species and whether it is distributed widely across Palawan or is localised to certain parts of the island, as this will affect its area of occupancy and may call for a change in its extinction risk category once additional information becomes available. (IUCN 2020)
REFERENCES
- Collins, N.M. and Morris, M.G. 1985. Threatened Swallowtail Butterflies of the World. The IUCN Red Data Book. IUCN, Gland and Cambridge.
- Dimaano, F., Larsen, R. K. and Pido, M. 2014. The emerging oil palm agro-industry in Palawan, the Philippines: Livelihoods, environment and corporate accountability. Stockholm Environment Institute.
- Fabro, K. A. 2016. Cleopatra's Needle in Palawan declared critical habitat. Rappler.
- Gimenez Dixon, M. 1996. The IUCN Red List of Threatened Species 1996: e.T2377A9435834.
- IUCN. 2020. The IUCN Red List of Threatened Species. Version 2020-3. Available at: www.iucnredlist.org. (Accessed: 10 December 2020).
- Malakunas, K. 2017. Philippines a global hotspot for environmental murders. Phys.org.
- 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.
- Panela, S. 2014. ‘Too many people’: Philippine island being deforested despite extensive protections. Available at: https://news.mongabay.com/2014/10/too-many-people-philippine-island-being-deforested-despite-extensive-protections/. (Accessed: 7th November).
- WWF 2018g: Morrison, J. 2018. Philippines: Islands of Palawan, Balabac, Ursula, and the Calamain Group. Available at: https://www.worldwildlife.org/ecoregions/im0143.