The Chestnut Tiger (Parantica sita) in Repulse Bay, prior to its capture. Photo courtesy: Yuet Fung LING.
While many Hongkongers head to Japan for their holidays, it seems one little traveller has flipped the script. A butterfly has made the reverse journey, flying an incredible 3,000 kilometres from Japan to Hong Kong—perhaps for its own winter getaway!
On August 18, 2024, two butterfly markers, Mr Masayoshi SHIMIZU and Mr Hiroki TAKIZAWA, spent the day placing stickers on the wings of the Chestnut Tiger butterfly (Parantica sita) in the Grandeco Ski Resortlocated in the Fukushima Prefecture, Japan. This species of butterfly is well-known for its long-distance migrations, and marking or tagging their wings provides valuable data about their movement, including how far they travel, the direction they take, and how long they survive. Over the course of the season, Mr Shimizu and Mr Takizawa spent six days at Grandeco and managed to tag an impressive 481 butterflies.
The Chestnut Tiger (Parantica sita) captured in Repulse Bay on Dec 21 2024 was tagged in Japan on Aug 18 2024. Photo courtesy: Yuet Fung Ling.
大絹斑蝶翅膀上貼有一枚印有日文和「8月18日」字樣的標籤。(凌悅丰提供)
Hiroki Takizawa (Left) and Masayoshi Shimizu (Right) worked together to tag the butterflies at Grandeco Ski Resort, including the individual captured in Hong Kong in Dec 2024.
清水正良和瀧澤宏樹說去年8月在福島捕捉大絹斑蝶作生態記錄及研究。(港大提供)
Fast forward to December 21, 2024, Dr Yuet Fung LING, a postdoctoral fellow in the School of Biological Sciences (SBS) at The University of Hong Kong (HKU), was out catching butterflies in Repulse Bay. To his surprise, he spotted a male Chestnut Tiger – a rare species in Hong Kong – with a sticker on its wing. Even more surprisingly, written on the sticker were Japanese characters and the date ‘Aug 18’, confirming that this butterfly had been tagged in Fukushima four months earlier.
Team leaders of the Danaid Butterfly Research Hong Kong: (from left to right) Yuet Fung Ling, Emily Jones, and Timothy Bonebrake. Photo courtesy: Timothy Bonebrake.
凌悅丰(左)在記錄該隻大絹斑蝶的資料後，已將其放歸野外。(港大提供)
Dr Ling works with Professor Timothy BONEBRAKE and PhD candidate Miss Emily JONES at SBS. Together, they lead the Danaid Butterfly Research Hong Kong, a group dedicated to studying the seasonal movements of danaid butterflies in Hong Kong. By carefully placing URL-branded stickers on butterfly wings (similar to those used in Japan), the group tracks the movements of species through public sightings and reports. Through mutual colleagues, the research team managed to connect with Mr Shimizu and Mr Takizawa to confirm the record. The adult butterfly was at least 124 days old and had travelled more than 3,000 km (3,016 km straight-line distance from Grandeco to Repulse Bay).
This discovery set a new distance record for the species and is only the third time a butterfly has been detected migrating from Japan to Hong Kong. The previous record, set in 2011, involved a Chestnut Tiger that flew an estimated 2,423 km and lived for 82 days.
‘It’s an astonishing feat. For a little insect like this to fly more than 3,000 km and do so for more than 100 days just shows the physiological capacity for these creatures,’ noted Professor Timothy Bonebrake. ‘The record also highlights how much is left to discover about these important migratory phenomena. To gather data to effectively conserve these migrations, we need more international collaboration like this and active participation from the public.’
After recording the butterfly, Dr Ling released it back into the wild. Whether Hong Kong is its final destination or just another stop on its journey remains a mystery.
Researchers are calling on the public to help unravel these mysteries. If you spot a butterfly with a sticker on its wings, report it to the Butterfly Research Hong Kong. Every sighting brings us closer to understanding and protecting these amazing migratory species.
To find out more about danaid butterflies and the research efforts of Danaid Butterfly Research Hong Kong, please visit:
https://www.instagram.com/danaidhk/
香港大學蝴蝶研究團隊發現，有香港罕見的大絹斑蝶 (Parantica sita) 遷徙逾 3,000 公里由日本抵港，創最長飛行紀錄。港大生物科學學院博士後研究員凌悅丰上月21日在淺水灣進行蝴蝶研究時，發現一隻大絹斑蝶翅膀上貼有一枚印有日文和「8月18日」字樣的標籤，顯示該大絹斑蝶 4 個月前曾在日本福島被標放。
港大研究團隊透過其他斑蝶標放組織，聯繫到標放該隻大絹斑蝶的日本蝴蝶標放人員清水正良與瀧澤宏樹，確認牠最少生存了 124 天，飛越超過 3,000 公里。這是有紀錄以來，大絹斑蝶第三次由日本飛抵香港，亦是全球大絹斑蝶已知的最長移動距離，打破了 2011 年另一隻大絹斑蝶歷時82天飛越 2,423 公里的紀錄。
清水正良和瀧澤宏樹表示，去年8月18日在福島縣 Grandeco 滑雪場捕捉大絹斑蝶作生態記錄及研究，並逐一在蝴蝶翅膀上加上標籤，6天內共標放多達 481 隻大絹斑蝶，由於大絹斑蝶具有長距離遷徙習性，研究可收集牠們遷徙的飛行距離、移動方向及生存時間等寶貴數據。
凌悅丰與港大生物科學學院教授 Timothy Bonebrake 和博士研究生 Emily Jones 共同帶領「香港斑蝶研究」團隊。Timothy Bonebrake 認為，這是難以置信的壯舉，尤其蝴蝶體型細小竟能歷時超過 100 天並飛逾 3,000 公里，展現出昆蟲驚人的生理本能，又指這項發現凸顯斑蝶遷徙的奧妙。這項發現凸顯斑蝶遷徙的奧妙。我們需要更多類似的國際合作和公眾積極參與，才能收集更多數據，以了解和保育這些重要的遷徙現象。
該隻大絹斑蝶已放歸野外。至於香港究竟是大絹斑蝶的遷徙目的地，還是僅作為中途站，目前仍是一個謎。研究團隊希望公眾能參與解開斑蝶遷徙的謎團，呼籲市民如發現翅膀上貼有標籤的蝴蝶，可報告予香港斑蝶研究團隊報告。