, Nymphalidae 
, Pieridae 
, Lycaenidae 
, Riodinidae 
and Hesperiidae 
. Here, we depict all the butterfly species that have been spotted in Singapore, each represented by its primary wing colours and the family it belongs to.The disappearance of butterflies can serve as an early warning sign that all is not right in the environment. They are extremely sensitive creatures, heavily reliant on specific features within their habitat, particularly their host plants.
Disruptions to their habitat can hinder their life cycle, with climate change making these impacts even more unpredictable.
Biodiversity loss and climate change are interconnected crises. Shifting weather patterns, such as erratic rainfall or hotter temperatures, can cause species to decline. The loss of natural ecosystems could also lead to more planet-warming carbon dioxide being released into the atmosphere.
On Nov 1, the UN biodiversity conference COP16 ended with a decision that acknowledged the connection between climate, biodiversity and the ocean. Countries were urged to share their views to better align their climate and nature conservation policies.
Researchers estimate that even more native species have been lost here than what is noted in the Red Data Book. A 2020 study puts this figure at 236, which includes 104 species that likely went extinct here before they were discovered.
Over the past 160 years, almost half of Singapore’s native butterfly species have disappeared, according to the scientists. Deforestation and loss of plant species were major factors driving these local extinctions, especially for butterfly species that depend on forests.
But despite rapid urbanisation, our small island city-state is still home to rich biodiversity, including more than 2,000 plant species and 360 butterfly species.
What do butterflies need to thrive? It all begins with the caterpillar.
Caterpillars are often viewed as pests – voracious eaters that damage plants – but without them, we would not have the beautiful butterflies that follow.
Butterfly caterpillars are known to be picky eaters, often feeding on only one or two specific plant species, also known as their host plants.
“Being a specialised eater offers butterflies and caterpillars an evolutionary advantage of being very efficient at finding and digesting their food,” said Dr Anuj Jain, director and principal ecologist at bioSEA, a company that specialises in ecological design.
Let’s follow the life cycle of the common rose and look at the threats it faces in each stage.
The biggest threat to the common rose butterfly is difficulty in finding a host plant to lay its eggs on. Its original host plant, Aristolochia jackii (Jack’s Dutchman’s pipe), is thought to be locally extinct, so it now relies on a close cousin, the Dutchman’s pipe.
Ah! Here she finds the Dutchman’s pipe plant, or Aristolochia acuminata. This near-native ornamental plant is found in parks and gardens. The plant will be the home for her offspring, as well as their primary food source.
The female common rose can lay about 20 to 25 eggs at once. Laid on the top or underside of leaves or on shoots, the eggs are vulnerable to insect predators and drying out in the heat. Experiments by Dr Jain suggest that only about 1 per cent to 2 per cent of the butterfly’s eggs survive.
The eggs take about three days to hatch. The common rose caterpillar is a voracious eater, munching its way through up to five leaves in a day.
At this stage, the caterpillar also faces the risk of dying from exposure to hot urban environments.
The use of pesticides is also harmful to caterpillars, as their limited mobility leaves them with no means of escaping or protecting themselves from the chemicals.
After about 15 days, the caterpillar is fully grown and forms a pupa. Pupae are immobile and defenceless, making them vulnerable to predators like birds and insects.
Finally, after about 11 to 12 days, the butterfly emerges from its pupa, ready to feed on nectar.
The common rose butterfly is relatively large and has a longer proboscis, or feeding tube. It typically prefers larger flowers that provide more nectar, or clusters of flowers such as Clerodendrums or Ixoras.
Typically, butterfly activities peak between April and May, following the blooming of flowers in February and March after a hot and dry spell, said Dr Jain. However, climate change may have affected these cycles.
Wildflowers can also attract butterflies. During the Covid-19 pandemic, when grass cutting was reduced, Singapore’s grassy patches were overgrown with weeds and wildflowers. This led to observers spotting more butterflies in Singapore.
Conversely, excessive pruning and landscaping of green spaces can harm insect populations, including butterflies.
Finally, butterflies also need to play and socialise, and areas with trees, shrubs, weeds and a variety of wildflowers are ideal playgrounds for them to thrive.
More than just beautiful creatures, butterflies, like other insects, play a crucial role in pollinating flowers, which is necessary for plant reproduction.
Caterpillars also contribute to the ecosystem – as they feed on leaves, they break them down and return vital nutrients to the soil.
Additionally, both caterpillars and butterflies are important food sources for various animals, including birds and reptiles.
But their significance extends beyond their ecosystem. “In the human environment, butterflies contribute tremendously to mental health,” said Mr Ganesh Kumar, who manages Woodlands Botanical Garden, a community garden in Marsiling.
The garden, which has become home to around 60 species of butterflies, including the common rose, has attracted visitors from near and far, with many saying how it has helped them escape their worries.
“I don’t think there’s anyone who is sad when they see a butterfly. It always uplifts their spirits.”
Why have Singapore’s butterflies disappeared?
The main drivers of local butterfly extinctions have been urban development and forest loss over the past two centuries. By 1900, more than 90 per cent of Singapore’s primeval forests had been cleared for timber extraction, agriculture and the creation of settlements, according to the National Parks Board (NParks).
In the middle to late 20th century, coinciding with Singapore’s rapid urbanisation after World War II, birds and butterflies were especially hard hit, according to research that looked into Singapore’s biodiversity over two centuries.
This decline was most likely linked to the loss of plant species, as butterflies depend on plants both as larval host plants and nectar sources. As a result, many butterfly species went extinct too.
But while Singapore has lost nearly 40 per cent of its biodiversity in the past two centuries, extinction rates slowed by the 21st century, the study found. This could stem from Singapore’s efforts to protect its forests.
Forests are home to many threatened butterflies. Most of Singapore’s remaining primary forests are in Bukit Timah Nature Reserve and the Central Catchment Nature Reserve.
This map shows where threatened butterflies were spotted from January to October 2024 by citizen scientists on iNaturalist.
Some critically endangered butterflies can be found only in specific environments. For instance, most harlequin butterflies live in Pulau Tekong, but a small population can be found on the main island in the Western Water Catchment and Sungei Buloh.
Many butterflies categorised as near-threatened have been spotted in Singapore’s green spaces, including urban parks and nature corridors.
Can butterflies thrive in an urban environment?
Although many of Singapore’s butterfly species are dependent on forests, urban gardens and parks can also provide a habitat for them.
“Personally, I would like to use Singapore as a positive example of environmental rejuvenation and regeneration,” said Mr Khew Sin Khoon, head of Singapore butterfly interest group ButterflyCircle.
Mr Khew, an architect by training, cites projects such as Gardens by the Bay — which he was involved in — as examples of how urban development can enhance biodiversity. While the Gardens’ iconic glass domes receive most of the attention, he emphasises that its 90ha of open space has supported a wide range of plant species, attracting around 70 different butterfly species.
Butterflies spotted in downtown Singapore
He has also observed the growing awareness of and research on caterpillars and their host plants. This has led to more widespread planting of host plants across the city.
For example, NParks has carried out targeted planting of certain caterpillar host plants such as the Dutchman’s pipe in urban gardens and parks such as the Singapore Botanic Gardens, HortPark and Woodlands Waterfront Park.
“We’ve gone away from the past of creating botanical gardens for the sake of aesthetics and for the sake of planting pretty, colourful flowers,” said Mr Khew. Instead, the focus has shifted to understanding nature more deeply and creating environments where nature can thrive.
Butterflies spotted in parks around the Southern Ridges and Woodlands
Other host plants have also been planted in Bishan-Ang Mo Kio and Pasir Ris parks.
“Designing a successful butterfly garden involves considering the varied micro-habitat, host and nectar plant requirements of butterfly species,” says Ms Sophianne Araib, group director at NParks’ National Biodiversity Centre.
Planted routes, designed to mimic the natural structure of forests, link green spaces in Singapore, facilitating the movement of butterflies and other wildlife through urban areas. These nature ways, or green corridors, help connect areas of rich biodiversity, such as the nature reserves.
According to Dr Jain, one of the biggest threats to butterflies in the city-state is the widespread use of insecticide, especially during dengue outbreaks. While these chemicals target mosquitoes, they also harm other beneficial insects, including butterflies and their caterpillars.
How will butterflies be impacted by climate change?
One of the earliest studies on the impact of climate change on butterflies was published in 1996 by ecologist Camille Parmesan, who is currently based in France. She examined populations of the Edith’s checkerspot butterfly and discovered that it was shifting to higher altitudes and moving away from the Equator in search of cooler environments.
Butterflies are sensitive to changes in temperature, said Dr Parmesan. They rely on the sun to generate heat for their flight, as well as to grow, feed and mate, she added.
While the effects of climate change on butterfly populations in Singapore have not been extensively studied, one study by Dr Jain and his colleagues looked into the effects of extended drought periods on tropical swallowtail moths.
They found that physiological changes in the moths’ host plant during dry spells make it more conducive for breeding. This results in peak populations, which could occur more frequently with extended drought periods due to climate change.
Urbanisation also deals a double whammy to the moths, which are drawn to urban lights. The strongest fliers make their way to the city, but since urban areas lack suitable host plants — which are found only in forested regions – many moths die without reproducing.
Over time, the population will decline as the fittest moths are lost, leaving only the weaker ones in the forest. Dr Jain postulates that butterfly populations could similarly peak during dry spells, and the same trend could apply.
There is also anecdotal evidence of how butterflies are being affected by shifting weather patterns.
The year 2024 is on track to become the hottest on record. Mr Kumar has observed the effects of this extreme heat and prolonged dry spells on the plants at the Woodlands Botanical Garden.
In previous dry seasons, he would water the garden if it did not rain for 10 days. But because of the heat during 2024’s drought, he had to do so after only three dry days.
As the plants wither, insects like butterflies are left without food. “Working outdoors as a gardener, I see the real effects of climate change,” he said.
The disappearance of Singapore’s butterfly species reflects the global insect species decline, as more face extinction due to pesticides, habitat loss and climate change – with catastrophic repercussions on wider ecosystems.
“Butterflies are the canary in the coal mine. They are just the indicators to tell us what’s happening in the insect world. But actually, the bigger problem awaits us.”