About 100,000-150,000 species of butterflies have been described; perhaps half that number remain to be discovered. Although there are important concentrations in the Arctic and temperate regions, most species are found in the tropics. There, the diversity of colors and forms is dazzling; every imaginable combination of hue and color is displayed. And many tropical butterflies are enriched with "structural" colors, which cause the wings to flash iridescently in the sun as they bend the light they reflect.
Although butterflies have long been admired and often depicted in art, they have been seriously studied only since the end of the seventeenth century. Linnaeus, in his Systema Naturae, placed the small number of butterflies then known in the single genus Papilio. Today that genus is restricted to the true swallowtails, and more than 700 genera of butterflies are recognized.
The Butterfly Trade
Last century, as knowledge of butterflies grew and methods of preserving them improved, they become popular collectors' items. Wealthy naturalists such as Rothschild and LeMoult dispatched collectors to all parts of the world for specimens. Today the trade in butterflies is even more extensive.
There are three major kinds of butterfly and insect trade. In one, large numbers of common species are collected in the wild and processed for use in ornamental objects such as coasters, mats, and lampshades. This is a low-value, high-volume industry that is both labor- and capital-intensive. It frequently uses "chipped" or slightly damaged butterflies. It often sells butterflies with paper bodies and only the wings of actual insects, which seem to be acceptable to a large part of the buying public.
The Taiwanese butterfly trade is an example. It operates on a large scale. At least a dozen Taiwanese factories employ scores of workers to capture and process butterflies. Estimates of annual sales vary from 15 million to 500 million butterflies. Taiwanese butterfly wings pasted onto paper bodies with pig-bristle antennae are used in ornaments and household objects from wall hangings to clear-plastic toilet seats. The bodies are recycled as pig feed. Despite this massive trade, Taiwan's wild butterfly populations seem to be remaining steady.
Similar, though smaller, industries trafficking in common butterflies are found in Korea, Malaysia, Hong Kong, Brazil, Honduras, and several African nations. The famous blue morpho butterflies of the American tropics enter the trade at the rate of some 50 million per year. Nearly all of these are the brilliant iridescent males, and biologists believe the number sold could be doubled without harming the overall population.
The second type of trade involves higher value and lower volume. This produces a vastly different product from the paper-bodied butterflies bound for novelty stores. It is exemplified by the operation in Papua New Guinea where sales are to collectors, museums, and students, and the specimens are high-quality insects in good to perfect condition, usually bearing scientific data. Because of the relatively high value per specimen, this trade can be carried on by fewer individuals in a nonfactory setting, and it is well suited to village industry, provided there is supervision and a quality-control checkpoint.
The third type of butterfly trade is for high-quality, expensive ornamental items, such as glass cases, domes, wall mounts, or jewelry containing beautiful insects. Brazil, for example, has a thriving jewelry trade based on the iridescent blue morpho butterfly. This type of trade can also furnish high-paying outlets for village-farmed insects.
In all three divisions of the butterfly trade, dealers fulfill an essential role. Few collectors and scientists can travel the world collecting their own specimens. Some dealers have established reputations for honesty, some have not. Exploitation of suppliers and customers alike has been rife. Few dealers are careful to attach accurate locality data to their specimens; some make serious mistakes in identifying them. (To combat this problem, British insect dealers have formed an association to monitor conservation-related activities and improve professional practice.)
Generally, dealers supply specimens bred from the caterpillar or chrysalis and described as "ex pupa." Unless butterflies are caught immediately after emerging from the pupa the fragile wings tear and the scales detach to produce "worn" specimens.
Classifying butterflies is difficult. Their most obvious features, the color and pattern of the wings, vary greatly; individuals and populations of the same species often look quite different. This has led to the dubious naming of many species and subspecies. And the uncertainties it causes have led some biologists, especially those working in ecology and genetics, to name populations rather than species or subspecies. However, populations frequently evolve, and this introduces a further uncertainty. Much additional work on basic butterfly systematics is needed. The knowledge gained should contribute particularly to the conservation of endangered species.
Butterfly conservation is still in an early state of development, bedeviled by scarce or incomplete information. The conservation status of even the most thoroughly studied butterfly species is known in only a few areas. The distribution and status of most species is essentially unknown, and proposals for conservation measures are largely based on guesswork. Nevertheless, some conservation programs have been enacted. Most have concentrated on designating endangered species and banning their collection.
The greatest threat to butterflies and other insects, however, is habitat alteration. On several continents some species have already become extinct or endangered when humans altered the special environment they require. The importance of protecting butterfly habitats should not be underrated. Many species are restricted to very small areas, particularly to individual islands (Corsica, Sardinia, Jamaica, Madagascar, Sumba, the Comoros, Fiji, the Solomon Islands, Manus, and the Duke of York Islands, for instance). Such species are vulnerable to extinction because nearly all island habitats are fragile and are changing rapidly.
Although it is uncommon for insect species to be dangerously reduced merely by the capture of specimens, renewed commercial interest in butterflies gives rise to concern for their conservation. Most insects reproduce rapidly, and their high fecundity enables them to replace such losses in a generation or two - provided the basic environment has not been altered.
But there are certain species of butterfly that reproduce slowly and are therefore more threatened by collection. The unusual birdwing butterflies of New Guinea, for example, produce only small broods. Moreover, these rare species command higher prices. Because this makes them particularly vulnerable, legislation to protect birdwing butterflies has been instituted in both parts of New Guinea - Papua New Guinea and Irian Jaya.
Accordingly, to save Queen Alexandra's birdwing (the largest and most threatened of the birdwings) from extinction, several wildlife management areas have been set up in Popondetta on Papua New Guinea's north coast. The government is also setting up refuges, administered by village councils, to preserve and protect other birdwing butterflies and wildlife resources. This habitat conservation is an important adjunct to the butterfly farming program.