By Liu Jiawen, reporting
Purple Butterfly Valley? Where is it? Many people hearing the name “Purple Butterfly Valley” would assume it’s the name of a place, but this dreamy and poetic term actually refers to an ecological phenomenon where various species of danaine butterflies gather for overwintering. Taiwan currently has over 30 known Purple Butterfly Valleys, with the Maolin Scenic Area being the most densely populated—with at least 8 locations. From December to March of the following year is when the purple crow butterflies overwinter, making it the best time for butterfly watching. To enjoy the romantic sight of butterflies fluttering all around, consider visiting the Maolin Scenic Area for an ecological trip during the holidays.
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Every year, large numbers of purple crow butterflies fly to the Maolin Scenic Area to overwinter. On clear mornings, you can see flocks of them flying and foraging. (Photo by Liu Jiawen, SpotTown)
Taiwan is home to 13 species of danaine butterflies. Aside from the great Mormon butterfly found in the Hengchun area, the other 12 can all be seen in the Maolin Scenic Area, with the purple crow butterfly being the most numerous. The scales on the wings of the purple crow butterfly refract sunlight, displaying dreamy hues of light purple, vivid purple, or bright blue depending on the viewing angle. Japanese entomologists call this phenomenon “phantom color.” When large numbers of purple crow butterflies take flight, it looks like streams of purple light darting about—absolutely stunning. When is the best time to watch them? The answer is after sunrise, around 7 a.m., when the butterflies emerge from the valleys to bask in the sun, sip water, and seek nectar. Toward the end of the overwintering period, you can also observe courtship, chasing, and mating behaviors among the purple crow butterflies. By around 11 a.m., they usually return to their resting places.
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The wings of the purple crow butterfly refract sunlight, displaying dreamy hues of vivid purple or bright blue depending on the viewing angle. (Photo by Liu Jiawen, SpotTown)
Taiwan’s Purple Butterfly Valleys and Mexico’s Monarch Butterfly Valley are recognized as the world’s two major overwintering butterfly valleys. To protect this precious world-class ecology, the Maolin Scenic Area has developed ecological parks and butterfly-watching trails where the public can get close to purple crow butterflies without damaging their habitats. Liao Xiu-yue, a guide from the Maolin National Scenic Area Administration, reminds visitors not to capture or touch the butterflies, as this can cause their wing scales to fall off, affecting their flight ability and reducing their lifespan. Some people may also be allergic to the scales. Therefore, apart from taking photos and observing, avoid any actions that could harm the butterflies.
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The “brush organ” is a unique structure found only in male butterflies. It flips out from the abdomen during courtship or when captured, resembling a yellow pom-pom. The public is reminded that only experts should handle butterflies to minimize harm. (Photo by Liu Jiawen, SpotTown)
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In the Maolin Scenic Area, besides purple crow butterflies, you can also spot up to 12 other species, including the common crow butterfly. (Photo by Liu Jiawen, SpotTown)
The “2011–2012 Maolin Purple Butterfly Valley – Biennial Butterfly Watching Event” will be held from now until March 4 of next year. Free guided eco-tours of the purple crow butterflies are available every Saturday and Sunday, with a daily limit of 250 participants. Visitors need to book in advance via the event’s official website.
Event website: www.maolin-nsa.gov.tw/Event/2011_butterfly