IUCN Red List Conservation Status: Endangered
Papilio chikae, the Luzon Peacock Swallowtail, is a relatively recent discovery, found in 1965 on Mt St Thomas in the southern Cordillera Central of Luzon, northern Philippines. It has since been found on a number of occasions on peaks near Baguio and Bontoc. Essentially a species of areas above 1500 m in the western montane zone, it is a glacial relict of continental origin. The Baguio area is a popular tourist resort and this naturally rare species is believed to be endangered by over-collecting and probably by habitat alteration.
Description
This beautiful green-black, red and purple, long-tailed butterfly, is one of the gloss swallowtails or peacocks. It is relatively large with a forewing length of 55 mm (2, 6, 12). Although P. chikae is now widely accepted as a good species, doubts have been raised in the past. In particular, its relationship with Papilio lorquini Reakirt, 1864 has not been clarified (8). The male upper forewing has golden-green scales evenly scattered over the black ground colour. The upper hindwing ground colour is also black with scattered golden-green scales. A large green submarginal patch in the apical area turns blue in the summer form. The red submarginal lunules may be well developed, especially in the summer form, and have purple inner margins. The tail is relatively long, narrowing at its base, and with dense blue-green scales on its upper surface. The lower forewing is sooty black with a broad pale grey band tapering to the inner margin, where it is pale blue. The lower hindwing has whitish scales extending outwards from the cell over the black ground colour. The submarginal lunules are enlarged and red-orange, with broader and paler purple inner margins (6, 12). The female has a longer tail to the hindwing and better developed submarginal lunules. These join with marginal spots to form large red hoops towards the anal angle (12).
Distribution
Papilio chikae is endemic to Luzon in the northern Philippines . It is only known from the north of the island where it is found in the Baguio and Bontoc regions of the Cordillera Central (12) . The type locality is Mt St Thomas (Mt Santo-Tomas), a 2258 m mountain to the south of Baguio city (5). The species has not been found in the nearby Sierra Madre range in north-eastern Luzon much of which may lie at too low an altitude (11). P. chikae is a member of the paris group, which is mainly distributed in eastern continental Asia. Of the twelve species in the group, only two others reach the South East Asian islands, paris is found in Sumatra and Java as well as India, Burma, China and Hong Kong, while karna occurs only in Java, Sumatra, Borneo and Palawan.
Habitat and Ecology
Papilio chikae flies at altitudes above 1500 m (11) and can be found almost all year round, with a short recess from November to January (12). The spring form is found from January to early April and the summer form from mid-April to November. While the summer form is larger, the spring form may be rather brighter in colour (12). Such seasonal variation in a species of the montane subtropical habitat is taken to indicate its status as a relict species of continental origin (1, 12). It probably pushed southwards from China and Taiwan during the last ice age, when water accumulated as ice at the poles and the sea level fell considerably. As the ice retreated and sea levels rose once again P. chikae was left behind as an isolated species. The young stages and foodplant of Papilio chikae are unknown, but in other species of the paris group the larvae are found on Rutaceae and have thoracic and first abdominal segments with a dorsal, shield-like raised area, no metathoracic band and reduced eye spots (4). The habitat is broken countryside with open grassy meadows, scattered bushes and small copses in ravines and rifts (11). The most common tree is the Benguet pine (Pinus insularis). Associated butterflies include Papilio benguetanus, Pieris canidia, Eurema hecabe, Vanessa indica and Argyreus hyperbius (5, 7).
Threats
This elusive and rare butterfly clearly has a very limited distribution. Even within the Cordillera Central, it may be restricted to peaks over 1000 m above sea level. Access to the peaks of the Baguio and Bontoc areas seems to be relatively simple. A motorable track runs the whole way up to the type locality on Mt Saint Thomas, but mist often reduces visibility and activity of the butterflies.
This and other species of gloss swallowtails are regarded by collectors as great prizes (9). The fact that the sale of just a few specimens of P. chikae on the international market would at one time have paid for a return trip from Japan was a matter for concern. As J.N. Jumalon has put it, P. chikae “is like a criminal with a price on its head” (9). No doubt most collectors exercise restraint, but with easy access and high prices, the temptation to over-collect must be great. Tsukada and Nishiyama explain how easily the butterfly can be attracted by decoys and note that its flight is so slow that it can be captured almost without fail (12). It has been noted that employees in radio stations on the mountains all keep butterfly nets, presumably for commercial collecting (3). D’Abrera records that some Japanese collectors have been known to offer 35 mm cameras to local collectors in exchange for specimens (2). Although it seems that the market in Papilio chikae has decreased considerably in recent years, there is still a great need for restraint in collecting.
It has not so far been possible to assess the extent of habitat disruption within the limits of distribution of P. chikae. Baguio is noted as being the summer capital of the Philippines (5), and a summer resort which swells to several times its normal population in April and May (12). One might, therefore, expect fairly heavy recreational pressure on the habitat from human use at certain times of the year. Even so, many slopes, gullies and other potential breeding areas for the butterflies may remain uneconomical for agriculture and forestry and may, therefore, be effectively protected from these more significant threats to wildlife.
Population growth and the development of tourism are said to be the reason for new roads being built to improve the accessibility of villages in the hills of the Cordillera Central (9). This will inevitably result in some destruction of the alpine vegetation. Other forms of development add to the problem: mining has devastated large areas in the north of Luzon. Disturbance by fire is a further possible threat.
Development and population growth are certainly reducing the range of available habitat in the Cordillera Central, but over-collecting does seem to be the most serious threat (11), an unusual situation for a butterfly. It is clear that considerably more information on Papilio chikae is needed and that this should be obtained as expeditiously as possible.
Conservation Measures
The most immediate requirement is a survey of the Cordillera Central in the appropriate season to assess the distributional limits of the species. At the same time observations on young stages and larval foodplants should be made. This would permit an assessment of the potential for captive breeding of the butterfly. The high prices commanded on the international market indicate the demand for the species and a controlled breeding and farming programme would serve to meet the demand, provide local employment and conserve the wild populations of the butterfly. Monitoring and perhaps even legislative control of collecting might be required.
It appears that there are no functional protected areas in the Cordillera Central of Luzon, although the Philippine national parks system has been under review (10). To judge from the popularity of Baguio in the summer, protected recreational wilderness areas would be an asset to the local people and visitors as well as serving to protect the wildlife of the region. However, great efforts will be needed to convince the many disadvantaged people of the Philippines that conservation will have long-term benefits.
References
- Ae, S.A (1983). In litt.,March 18.
- D’Abrera, B. (1982). Butterflies of the Oriental Region. Part 1. Papilionidae and Pieridae. Hill House, Victoria, Australia, xxxi + 244 pp.
- Dacasin, G. (1984). In litt., 25 April.
- Hancock, D.L. (1983). Classification of the Papilionidae (Lepidoptera): a phylogenetic approach. Smithersia 2: 1-48.
- Harada, M. (1965). The capture of Papilio chikae. Tyo To Ga (Transactions of the Lepidopterists’ Society of Japan) 16: 48-49.
- Igarashi, S. (1965). Papilio chikae an unrecorded Papilionid butterfly from Luzon island, the Philippines. Tyo To Ga (Transactions of the Lepidopterists’ Society of Japan) 16: 41-49.
- Iwase.T. (1965).How Papilio chikae was found and named. Tyo To Ga (Transactions of the Lepidopterists’ Society of Japan) 16: 44-47.
- Jumalon, J.N. (1969). Notes on the new range of some Asiatic papilionids in the Philippines. The Philippine Entomologist 1(3): 251-257.
- Jumalon, J.N. (1984). In litt., 10 July.
- Pollisco, F.S. (1982). An analysis of the national park system in the Philippines. Likas-Yaman, Journal of the Natural Resources Management Forum 3(12): 56 pp.
- Treadaway, C.G. (1984). In litt., 25 May.
- Tsukada, E. and Nishiyama, Y. (1982). Butterflies of the South East Asian Islands Vol. I Papilionidae. (transl. K. Morishita). Plapac Co. Ltd., Tokyo. 457 pp.
This page has been transcribed and edited, with permission, from Threatened Swallowtail Butterflies of the World: the IUCN Red Data Book by N.M. Collins & M.G. Morris. Whilst providing a sound baseline of information, it is in need of updating. The full volume, with references, may be downloaded from the IUCN Library System.