Great Purple Emperor
Hidden in Northeast China
My first memorable foray into the natural world was early in my childhood, watching little yellow butterflies fluttering around the tops of wild flowers in the fields near my house. I would watch them dance from flower to flower, the field feeling alive, bubbling with yellow insects. Even at my young age this was more than just play; I was, it turned out, creating a passion.
Those childhood experiences kindled my interests and opened my eyes to the natural world. It was, however, not until many years later, when I was in high school and saw my first butterfly specimens at a park souvenir shop that my childhood spark caught on and fully turned into a passion. We were at a park for a class field trip, and eventually the park guide led us to a display case near the corner of the room. I only heard the word “butterflies…” but that was enough for me. While other students casually glanced in the box and then made their exit, I made my way to the front of the counter and peered over the edge. I was transfixed at the perfectly posed butterflies in the display box. It was as if I had found a mine full of gemstones. The colors, shapes, and ornate patterns were otherworldly. Then I saw a flash of blue purple and my eyes were drawn to a few black and blue butterflies huddled in the corner. Their shape was not ornate or exaggerated like some of the others, but their color was enchanting: the deep dark blue almost glistened, beaming with a dark sapphire blue. I looked at the name plate below and saw “great purple emperor”, followed by their scientific name, Sasakiacharonda . There they sat, aged but clearly as vibrant as the day they were collected, standing out amongst a vast sea of butterflies.
Over time, those butterflies became my obsession. After sifting through a mountains worth of information, anything I could find on the species, I learned that the great purple emperor was first discovered in Kanagawa Prefecture, Japan. The first specimen collected was a male, its metallic blue wings catching the light of the sun and giving off a surreal purple iridescence when it was caught, giving it the name “the purple butterfly”. Soon thereafter, once the world saw its beauty, it was renamed the “great purple emperor”. From unknown to emperor in a short period of time. How fitting.
The love affair between the Japanese and the emperor lasted, the butterfly becoming so cherished that, in the 1950s, it was selected as Japan’s national butterfly. These butterflies can be found from the northernmost prefecture of Hokkaido, to the southern edge of the Kyushu. Outside of Japan they occupy a wide range, from the Korean Peninsula southward through China and on to Vietnam and northern Laos. They are, truly, an Asian butterfly.
The first time I saw one of these flying metallic gems alive was in Guangdong, China, many years after that first specimen-box encounter. I was wading through a humid primary forest, the sky blocked by the thick canopy of trees that were flooded with a cacophony of tropical birds and insects. I was actually trying to find one of those hidden birds when a streak of purple raced across my eyes. By this time, I was experienced enough and I knew what it was, and the chase was on. I followed its glittering path and watched it glide, accelerate then dive, eventually becoming stationary, seemingly standing on the thick humid air. Its strong wings beat out a rhythm,
metallic purple reverberating through the air! I tried to take pictures, but it was almost impossible—it moved too fast, taunting me with its beauty but never letting me close enough to photograph. Several butterfly enthusiasts with me commented on my somewhat valiant attempts, noting that its beauty always attracts people but its flying acumen and alertness is just too good. “It’s the hardest species to catch on film,” I heard in the background as I tried, and failed, to sneak up on one resting on a branch. I learned quickly that the mighty emperor is a paradox of showy but shy, extravagant but humble.
I have encountered the great purple emperor many times since that first sweaty encounter in those virgin forests of Guangdong; however, no matter where I go and how many impressively beautiful wild emperors I see, the ones I find for sale or available as specimens are all larger and more ornate than the wild ones I see in natural forests. I have trekked much of their range throughout China in search of the giant emperors, and have seen more than my fair share, but I have still never seen—in the wild—butterflies as spectacular as those for sale or on display as specimens. Why? Where do these ones come from?
The answer, in part, is geography: almost every one of these outlier specimens comes from the same mysterious valley, where butterflies grow larger, more colorful, and more sublime. Highly secretive, the butterfly collecting world has not willing been eager to divulge such information, but the question has been on my mind for a long time: where is this secretive butterfly valley?
The Source of China’s Great Purple Emperors Specimen
In the summer of 2016, the editor of Chinese National geography magazine contacted me, telling me that a secret “butterfly valley” in the northeast of China had been discovered, and inquired if I had interest in traveling to see it. China’s northeastern region is known to be cold, a hostile climate for butterflies, and also heavily industrialized. It was difficult to imagine that in the chilled industrial heart of northern China there could be a haven for butterflies. I worried that the phrase “butterfly valley” was nothing more than a tourism tactic, a way to attract visitors to an otherwise unwarranted destination. An exaggeration, I assumed, ready to turn his offer down. While I was saying as much over the phone, I received an email. I opened the attachment and saw on my screen hundreds of big, metallic purple butterflies hanging off the bark of a single tree trunk. A second photo showed a wider view, and I saw a forest painted purple—the butterflies literally cloaked the forest.
I felt my skin tingle. Excitement and confusion washed over me. I was not only stunned by their abundance, but also because I had done my research and knew that while their range is geographically vast, they are, as a species, not commonly spotted in large groups. To find so many, in such a small piece of what should be challenging terrain—logged forests, plantations, and urban industry—was astounding. I was determined to go see.
True to my word, later that summer I arrived in Liaoning Province’s Nanzamu Town, in search of the purported “butterfly valley”. I pulled up a seat at a restaurant near my hotel and started chatting with locals, hoping to get a feel for the region and its people. And the butterflies. The name “Nanzamu”, one man told me, was originally a Manchu name given to the region meaning “wild rose in full bloom”. It reflected, he continued, the beauty and the biological wealth which the first people to settle here were surrounded by. I was more than a little shocked: the mountains here are not high, more like a range of hills than mountains, and are today covered with mono-cultured plantations intertwined with stubbly secondary forest, themselves patched with clear-cuts left from the thriving—and financially vital—logging industry. Looking out across these hills of tea, fruit, and stump-filled forests, I wondered what they used to look like; what was the original Nanzamu that attracted and held on so tight to the hearts of its people, and the shy metallic butterflies?
This region is an active and prosperous logging region, famous for its bounty of large and straight trees. This fame is a boon to the logging industry, but a nagging concern for the wild forests. And herein lies the question at the heart of my origin concern: how could a place at once be both a hotspot for a thriving logging industry and a butterfly oasis? How could the preservation of one not preclude the other? I still had lingering doubts, but I remembered the pictures and the defiant urging of my editor, and I decided to stay positive. These doubts, however, were hard to subdue when I started asking locals a simple question: “Where are the butterflies?”
Almost to a person the responses were quick, and to the point: “What butterflies?”
Wandering the streets as I awaited my guide who, I was assured, would help me find butterflies, my heart felt heavy: the hills around me are covered in plantations; scarred treeless land forms a perimeter in the distance; the city before me is layered with industrial life and choked streets. Will this trip be fruitful? Is there actually a mystical “butterfly valley” somewhere in the industrial chaos of this land? I gathered my thoughts amidst the cacophony of the city and the swirling dust of passing trucks.
Suddenly, as my mind was arguing with itself, I was greeted by that unmistakable streak of purple that awoke my senses years ago in the sultry forest of Guangdong—a huge great purple emperor butterfly fluttered by my face and landed on a long since forgotten pile of cement beside the road. I almost screamed, half surprised and half elated— it was
so big, at least a third larger than the one I saw in Guangdong! This difference might not be obvious to a casual observer, but to my eyes, trained by years of nature photography and in hot pursuit of butterflies, the difference was remarkable. It was as stark as the difference between Asian and African elephants! My distraught heart ignited with hope and my energy was revived: there are butterflies here! As I reached for my camera the lone purple beauty flipped its wings and took off in to the industrial abyss, disappearing without a trace.
At that same moment, my guide, Mr. Zhou, approached and introduced himself. Noting my obvious naturalist and photographer attire, he said through a smile “You must be here to see the emperors!” I took note that he was a burly and strong man, skin tanned from years out in the sun, and assumed that he must be more than a guide. I soon found out that this was in fact so—he is also a businessman. Butterflies are his trade, and the forest is his office. “I kid you not” he said as we turned to face the distant forested hills, “Ninety percent of China’s great purple emperor specimens come from this area”.
I remembered reading accounts of uncontacted tribes—villages tucked away in the recesses of the Amazonian wilderness that remain without contact to the industrialized and commercialized world— and how they have been granted permission by governmental agencies and environmental groups to collect butterflies. These collected butterflies, acquired sustainably and strictly monitored, were sent to markets in Europe and North America, providing economic support to the villages. The arrangement seemed fitting for the people of the deep untouched Amazonia. I did not expect that, in the bustling world of industrial China, that this exact same system would be not only present, but flourishing.
A Rotting Love: The Unique Diet of the Emperor
I walked with Mr. Zhou through the dense city center and got into his car. We soon left the cemented world behind. The unexpected heat pulsing in through the car window made me feel like I am in
those southern tropical forests, and I thought to myself, reassuringly, “Well, at least it feels like butterfly territory”.
We pulled over. “From here we walk,” Mr. Zhou said, pointing up the logged hill to a green point near its crest, a line of forest that marks the point where the logging has stopped, for now. The sun above beat down with vengeance, and the air was frozen still. I soon realized that I was soaked with sweat and covered in dust.
Onward we hiked under the unforgiving sun, and the extra weight of my camera and tripod started to wear on my muscles, and my nerves. Wiping a torrent of sweat from my face, I paused and gazed off into the distance. I saw the green ridge that Mr. Zhou was aiming for, and noticed that between us and the ridge the word became, piece by piece, a little greener. Soon we came to a large Bunge’s Hackberry ( Celtisbugeana ), a deciduous tree with grey, fluttering bark with unique but inconspicuous leaves. “This tree,” Mr. Zhou mentioned as we stopped by its trunk, “is the only food of the great purple emperor larvae.”
I took a look at some of the lower branches to see if there are caterpillars feasting on its leaves. Clothes soaked and dripping from sweat, I exhaustedly kept balance by leaning on trees when I saw another tell- tale purple streak through the lens. I looked up from my camera, and there, fluttering in the air is an emperor. I followed it, as before, and watched it disappear. My spirits were again lit aflame, and I was drawn to the green forest ahead. We continued upwards and a few moments later my feet landed near a stump of a long- ago felled tree, and the ground alighted in movement. Purple butterflies by the hundreds rose up and took to the sky. In the still air I not only saw them, but could hear their soft fluttering wings adding a soft purple percussion to the silence. I followed one and it again landed on a nearby stump. It was sitting still with folded wings, its still body became camouflaged and was enveloped in secrecy by the background world. Then a gust of wind awakened the scene. The world of brown, covered in stumps and dried leaves, fluttered and shimmered in the breeze, a blanket of fluttering wings gently revealing their inner purple metallic glitter. In an instant, the world around me was covered in butterflies.
It is a common misconception that butterflies all share a penchant for flowers, attracted to the ornate and scented nectar of flowers. The reality is much less romantic, and those “elegant” butterflies that sip on nectar and pose for pictures perfectly on their floral buffet are not the whole story; other species, such as those making up this sea of glittering purple around us, prefer to eat from rotten and decaying plant material. The dead tree is their “flower”, the rancid and acidic sap their “nectar”. This is the great purple emperor’s niche, and a key to its success—surviving on the death of a tree.
I had read previously that this species has a soft spot for acidic sap that are part of the rotting process, and sitting here in the sweltering heat of the open land, I understood just how true this is. The shrubby, stump laden land around me was rife with a dizzying acidic stench—a heaven to the great purple emperor.
I approached a patch of butterflies and crouched down low, almost eye to eye. I feared that my presence would scare them away, but they continued to sit on the ground, wings slowly opening and closing, and all but ignoring me. I felt the collective vibration of their slowly swiping wings as they sucked up the juice of the rotting forest at my feet. I raised my camera slowly, waiting for an opportunity to take a photograph, and started to click. Suddenly a brave, bold male butterfly jumped from the ground and landed on my arm. Others followed suit, and soon my arm was speckled with emperors, and while I drank in the serenity and beauty of the moment, they wasted no time drinking in my salty sweat. As their straw-like mouths gorged themselves, I realized that, thanks to the heat and still air, I had become a buffet of a valuable nutrients often rare in forests.
The great purple emperor has a reputation for being shy. My encounters with them, up until this moment, have proven this to be true. Extremely alert, they rarely allow anyone to get close, remaining little more than purple streaks in the sky. But here, in the shoulders of an unlikely butterfly haven, the same species is not only unafraid of humans, but eager to bring them into their world.
The Future of Nanzamu’s Butterfly Valley
Following Mr. Zhou through the forest edge and into the richer and more diverse forest at the top of the ridge, the world became dark. Mr. Zhou walked through the sun-flecked forest, telling me everything he knows about the butterflies, now surrounding us by the thousands. And although, like him, many of the locals make their living catching and selling these butterflies, their collections do not threaten the emperor’s population. Business continues year to year, handed down generation to generation. But this business is not harming the population.
Part of the sustainability of collecting this butterfly species has to do with their breeding strategy. Compared to mammals, for example, which may give birth to only one or a few offspring each year, butterflies have very high reproduction rate. This is part of the R-K selection theory: either produce one offspring and give it great parental care, like hippos or elephants or humans, or produce many upon many, and let them relatively figure things out on their own, like butterflies. This is a tradeoff that seems to partition most of the wild world—plants included. Have one offspring and give it exceptional care ensuring its survival, or have many and assume that a good proportion will survive. Both strategies fuel future generations, but only those like these butterflies have
a strategy that is conducive to collection.
As a result, the butterflies flood the forest with offspring, evolutionarily “knowing” that only a portion will survive, but also that there will rarely if ever be a population decline. Even if mortality rates are high, as long as the environment is suitable and there are resources, the population is reproductively strong enough—each female butterfly will produce somewhere around 40 to 60 eggs a cycle, with upwards of 500 in its lifetime—and will recover from momentary losses.
As Mr. Zhou traced a route through the forest he was surrounded by glittering purple emperors. He told me that these butterflies are in his heart, and their beauty is, to him, nature’s magic. But there is more on his mind than just the beauty of these hills and their bounty of purple flying insects—if he and the other collectors can continue to harvest sustainably with proper ecological awareness and monitoring—this region of Nanzamu can be petitioned to be turned into a protected area. The vital remaining forests can be saved, and the regulations that follow legal protective status can help maintain this still-functioning but dwindling ecosystem. And, as part of the deal, if he and other collectors can continue to make a living from these forests, it may be a bright future for both. These questions are always on the minds and points of conversation among Mr. Zhou and his fellow collectors. In the end, while they want to make a living, they also want to make sure the skies are forever filled with these large purple butterflies.
“We’re losing daylight.” Mr. Zhou said almost under his breath as he stared at a cluster of butterflies. “This way” Mr. Zhou said, pointing to a generally normal looking patch of forest, thick with trees, stumps, shrubs and, of course, purple butterflies. Some were gliding, some diving, some contented with standing alone on a tree trunk, while others were in hot pursuit, males after females. After a few moments we broke through the edge of the forest and emerged once again to the hill slope and met up with the same trail that brought us here. We followed it down, guided by the orange setting sun, and left the butterflies and their hidden world behind.
In Japan’s Saitama Prefecture, there is a place called Arashiyama-cho that is famous for its great purple emperor butterflies. In fact, they have established the “Great Purple Emperor Butterfly Forest Centre”, a protected forest area divided into four sections: protected forest, display forest, experimental forest, and observation forest. While the forest is a busy location for researchers and staff year round, between June and August the observation forest is
It is hard to believe that despite the undoubtedly large population of great purple emperor in Nanzamu, only a few people are aware of the existence of this unique species. The local economy is supported by the wood industry and the dense forests hide the“butterfly valley” from sight. The Secluded “Butterfly Valley”
Distribution of Great Purple Emperor in Eastern Asia
In Japan, the great purple emperor is called the“national butterfly”and is listed among Japan’s near-threatened species. Yet in other countries of Eastern Asia, such as Korea, Vietnam and China, large populationsns can be found and so it was not found to be in need of f protection. Therefore, it was not included on the Internationalernational Union for Conservation of Nature (IUCN) Red List.
The “Bold” Butterflies Most butterflies are vigilant insects, yet during the expedition to the valley of butterflies, our photographer is surprised that the great purple emperors in Nanzamu show no fear of human presence. This is quite different from the behavior of their relatives in other places of China. In Nanzamu, the butterflies dare to fly just few inches away from us and sometimes they even land on our cameras and our shoulders. Perhaps the limited human disturbance here can explain this unnatural phenomenon.
Given the features that distinguish the great purple emperors in Nanzamu from those in other places, this town has become the most important specimen producer. Intact individuals are collected, then transferred and sold to colleges, museums and institutes. In fact, statistics show that more than 90 percent of China’s great purple emperor specimens come from the small town of Nanzamu. The Largest Specimen Producer
The Mystery of Scales Generally, the iridescent wings of butterflies are closely related to the microstructures of the covering scales. The angle of sunlight hitting the tiny“ridges”and“valleys”on the scales creates various colors. However, recent research indicates that light reflection does not fully explain the splendid wings of butterflies—some species are born with wings covered with colored pigment, making their wing color stable, unchangeable by any angle.
A Butterfly That Favors Stinky Foods
Influenced by paintings and movies, most people believe that butterflies and flowers go together. Indeed, some species, such as the swallowtail butterfly, do feed on nectar and people often find them resting on flower petals or stamen. But favorite foods of the great purple emperor are juices with sour or stinky smells. We find that by using stinky tofu (a famous, traditional food), we can attract large swarms of great purple emperors.
➲ A glass soaked in stinky tofu juice has attracted a great purple emperor that will stay and enjoy its meal for hours.
A Precious Photo of Mating Flight Every summer, swarms of great purple emperors gather and start their mating flight (also known as courtship flight). Each male spares no effort, flying high above the females in order to make them receive the pheromone secreted from his body. In Chinese painting, a pair of butterflies, chasing each other above flowers, is a frequently-adopted theme. In fact, such a scene is easy to spot with your eyes but hard to capture with a lens. Butterflies are tiny, fast insects and to shoot their movement requires highly trained skills, as well as patience. Thus, taking this clear photo of a pair of great purple emperors during their mating flight is an extremely difficult task.