Global Warming Causing Some Firefly Species To Vanish

The intermittent flickering of countless fireflies illuminates the night-time panorama in mangrove forests, such as the one in Kampung Kuantan in Selangor.

However, in recent years, the glow from these tiny bioluminescent insects has reportedly been “dimming”.

According to experts, firefly populations in Malaysia’s mangrove swamps are declining due to habitat destruction, which is partly caused by global warming. They warn the situation is also a sign that the survival of humans inhabiting the surrounding areas is under threat as well.

Firefly taxonomist Dr Wan Faridah Akmal Jusoh, who has been carrying out research on fireflies since 2006, told Bernama in the past their habitat was threatened by rapid development which contributed to environmental pollution. But now the insects are being threatened by global warming and climate change. 

“Global warming is causing sea levels to rise which in turn affects the biodiversity of mangrove swamps which includes fireflies. This means the lives of people residing in coastal areas are also under threat,” said the senior lecturer in biodiversity and conservation at Monash University Malaysia’s School of Science, adding a 2020 study by Saintilan et al revealed that most mangrove areas in the world, including Malaysia’s, are expected to be submerged by 2050 due to rising sea levels.

FOUR SPECIES ON IUCN RED LIST

Fireflies are classified under Lampyridae, a family of insects within the winged beetle order Coleoptera. In Malaysia, 60 firefly species have been identified so far with 10 of them found in mangrove swamps.

Photo from IUCN SSC Firefly Specialist Group

Wan Faridah said one of the main characteristics distinguishing land fireflies from the mangrove forest version is that the former fly individually while the latter, also known as congregating fireflies, fly in groups.

Of the 10 species found in mangrove forests, four have been listed as endangered species on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. The four are Comtesse firefly (Pteroptyx bearni), synchronous bent-wing firefly (Pteroptyx malaccae), the perfect synchronous firefly (Pteroptyx tener) and the nonsynchronous bent-wing firefly (Pteroptyx valida).

“Usually, two to three species of fireflies can be found breeding in a mangrove area, and these insects require suitable water levels and temperatures to ensure the survival of their respective species,” she said.

However, she added, the rising sea levels are altering these conditions, threatening the reproduction of fireflies during their metamorphosis phase – spanning from the egg laying to the larva, pupa and adult stages – as these insects are unable to swim or live in water.

NOT ENOUGH RESEARCH

Wan Faridah said despite the potential of fireflies as an ecotourism product, not much research has been conducted on these insects, making conservation efforts difficult.

Dr Wan Faridah Akmal Jusoh

“I carried out a study in Singapore and succeeded in discovering a new species in 2021 which I named Luciola singapura. This insect is categorised as critically endangered by the Singapore Red List (of threatened plants and animals).

“However, in Malaysia, very few studies on fireflies have been carried out and even if discoveries are made, it is difficult for us to confirm whether they are new species to science or just duplicates,” she pointed out.

The process of recognising new discoveries takes at least two years and requires research funding and facilities, she added.

“In some research projects, particularly in taxonomy and classification, I will need to visit natural history museums in the Netherlands, London (the United Kingdom) and France to compare reference specimens of fireflies that were discovered and collected by previous researchers especially during the colonial era.

“When foreign powers colonised our country, they not only took our nation's wealth back to their lands but also local biodiversity specimens,” she added.

Dr Wan Faridah Akmal Jusoh

Wan Faridah also said to support sustainable economic and ecotourism activities and ensure biodiversity conservation, she and several other organisations are currently conducting a study on the appropriate type or level of lighting needed to help conserve fireflies.

“We understand that a dark environment at night is necessary for the survival of fireflies but human needs for lighting cannot be ignored especially from a safety perspective.

“We hope our research will help humans to live harmoniously with other living creatures,” she said.

In conjunction with World Firefly Day, which falls on the first weekend of July, Wan Faridah expressed her hope to see firefly communities continuing to thrive worldwide alongside sustainable development.

Translated by Rema Nambiar