Warnings from butterflies
Warnings from butterflies
Embedded Files
2021 is a special year to butterfly lovers. The local green gruop Tai Po Environmental Association has found seven butterfly species in Hong Kong, which never happened in the past.
The seven species were Small Copper, Four-bar Swordtail, Great Nawab, Silver Royal, Fluffy Tit, Common Sailer and Lesser Gull. Apart from Small Copper, the butterflies originated from Southeast Asia such as India, Thailand or Malaysia. The discovery in 2021 is very unusual when compared to the past decade, where only 1 to 2 butterflies were occasionally discovered annually, and climate change is believed to play a role behind the scenes.
Escaping from heat
Butterflies are easily affected by external temperature, as they are ectotherms, unable to control internal temperature. To handle heat caused by global warming, species with high dispersal ability might move to a cooler place, which is usually located away from the equator.
Like many other places, Hong Kong is becoming hotter and hotter. However, to butterflies in South East Asia, this could be something good. The rising temperature makes Hong Kong an ideal place to reside in - warm enough yet favourably cool, compared to their 'home country' near to the equator.
Win some, lose some
On the contrary, Hong Kong is also losing some of the local species. Orange oakleaf (Kallima inachus) and Common treebrown (Lethe rohria) were once commonly found in the territory, yet their population has drastically decreased in the last decade. It is believed that they have moved poleward and stay in cooler places, such as the northern mainland China.
Only a matter of swapping species?
The warming climate is not only changing where we can see them, but also causing butterflies to emerge earlier - and unless their food or host plants adapt at the same rate, the insects could emerge too early to survive.
Global warming is undeniably changing the nature and pose a threat to all lives. The discovery of South East Asian butterflies is a subtle signal, reminding us that prompt actions must be made to reduce green gas emission, and slow down global temperature to further increase.
Page updated
Google Sites
Report abuse