Butterflies of Taiwan

by Scott Lin　　　　　
Executive Secretary of The Butterfly Conservation of R.O.C.

Taiwan has been called the "Kingdom of Butterflies".　And it's easy to see why. There are more than 400 species of butterflies in Taiwan - and 40 of them can be found nowhere else in the world!

There was a time during the 1960's when thousands of workers here were producing butterfly art and crafts.　It is estimated that some 10 million butterflies were caught every year.　Even though the export of butterfly products has long since stopped, the butterfly population continues to drop.　The loss of habitat is thought to be the main cause of this decline. In fact many rare and precious species of butterfly are now facing extinction.

7 BEAUTIFUL FAMILIES
Here are some representative Taiwan butterflies, organized into 7 families:

1. Swallowtails & Parnassians (the Papilionidae family)
The wings of the various Swallowtails are black with spots of red, white, yellow or green.　Taiwan is home to about 30 species from this family.　In the follow photos, the butterflies in the upper row are easy to find, even in the city.　The butterflies in the lower row are endangered.

2. Whites and Sulphurs (the Pieridae family)
The butterflies in this family tend to be rather small in size.　Their wings are light yellow or white, scalloped with red, black and yellow.　They like to fly over sunny clearings.　The scales of the butterflies in this family rub off easily when touched.

3. Milkweed Butterflies (the Danaidae family)
There are 13 species of Milkweed Butterflies in Taiwan.　They are poisonous.　They get their poison from the milkweed plants that they eat while in the caterpillar stage.　Animals that eat them get very sick and remember to avoid these brightly colored butterflies in the future.　Because of this, the Milkweed Butterflies are able to flutter around in the open air without fear.

4. Satyrs & Wood Nymphs (the Satyidae family)
Although this reclusive family is hard to find with its subdued colors, it is easy to identify once you see the circle patterns on their brown wings.　In order to identify the exact species, it is necessary to observe the size, number and pattern of the circles.　This family prefers to stay inside the forest or along its edge.　Unlike other butterflies, these don't suck nectar from flowers.　Instead they get their nourishment from fallen fruit and wood.

5. Brush-footed Butterflies (Nymphalidae family)
We have about sixty species from this family.　Not only do they vary in appearance, they also vary in their food source.　The species in this family are not always the passive creatures that butterflies are assumed to be.　It is not unusual to observe them occupying a treetop and fanning away other butterflies larger than themselves. They have even been known to chase away a passing swallow!

6. Skippers (Hesperiidae family)
Skippers have large bodies.　The end of each antenna is shaped like a hook.　They suck nectar and fly very fast.　Since they are hard to observe, they are known as the "phantom" butterflies.　Their posture at rest sometimes resembles that of a moth.

7. Gossamer Wings (Lycaenidae family)
The family is known as the Gossamer-Winged butterflies because their wings, like the fabric from which they are named, appear delicate and shimmering.　There are 110 species of Lycaenids in Taiwan.　The butterflies in this family are small with a wingspan of only an inch or so.　The wings are covered both by pigmented scales (blue, purple, or green) and by light-refracting scales.　Quite dazzling in the sunlight.

★ Butterfly Defensive Features★
In addition to laying lots of eggs, butterflies are able to maintain their populations because evolution has given them some protective traits that help keep them safe from their predators.

1. Camouflage:　The appearance of some butterflies resemble natural objects.　For example, the Fallen Leave Butterfly looks like a piece of dried leaf.　The appearance looks quite authentic.　The leaf design even includes "bite marks", making it look like the leaf has been visited by a hungry caterpillar!　As a result, the roosting butterfly is almost impossible to see.

2. Warning Coloration:　If an inedible insect can advertise its "inedibleness", it has a better chance of survival.　That's the case with the poisonous Milkweed Butterflies.　Members of this family - even those from different species - often share a similar wing pattern.　Unfortunately for the Milkweed Butterflies, non-poisonous butterflies from a different family have also evolved to have this pattern and to benefit from its protection (which reduces the effectiveness of the design).

3. Patterns and Behavior that Trick or Startle:　Most Gossamer-Winged butterflies have a very useful eye pattern on their rear wings.　When they rest on a twig and move their rear wings, the fake eyes look real.　A predator who mistakingly attacks the fake eyes might get a bit of the butterfly's wing, but the butterfly will be able to escape with its head uninjured.

The old "play dead" trick can also be found in the butterfly world.　The butterfly remains motionless until it gets the chance to escape.

Valley of the Blue-Spotted Milkweed Butterflies:
In May after the rainy season when the Eupatorium shimadai's brown flowers are blooming in the Yangmingshan Mountains (Yangmingshan National Park, nearby Taipei), many kinds of Milkweed Butterflies congregate in large numbers. Among the congregants, the Blue-Spotted Milkweed Butterfly is the most common.

Valley of the Purple Milkweed Butterflies:
When the winter monsoon comes down from the Northeast, tens of thousands of adult Milkweed Butterflies congregate on the clumps of trees and rest throughout the winter in some of the southern valleys (e.g. Maolin in Kaohsiung County).　Such migration in which the butterflies overwinter together is known only in North America and Taiwan.　In Taiwan, there are four principal purple Milkweed Butterflies in these congregations:
- Euploea mulciber barsine Fruhstorfer
- Euploea Eunice hobsoni (Butler)
- Euploea tulliolus koxinga Fruhstorfer
- Euploea Sylvester swinhoei

★ Conservation of Butterflies ★
Our butterflies serve as our canaries in a mine.　As long as the butterflies are thriving, we can take some comfort in feeling that our environment is in balance.　But our butterflies are not thriving - they are in decline.　And so we must take active steps to identify the problem and to find the solution.

With thoughtful conservation of this beautiful, delicate creature, it is possible that centuries from now people will still know Taiwan as the "Kingdom of Butterflies".