In the Ecuadorian Amazon, butterflies are an indicator of climate change. April 23, 2024

The butterfly traps are made of green nets that blend in with the forest canopy (Daniel MUNOZ)

By AFP - Agence France Presse

In the Ecuadorian Amazon, butterflies are an indicator of climate change.

Biologists on a trail in the Ecuadorian Amazon hold their breath as they hand out a foul-smelling delicacy to attract butterflies, essential pollinators increasingly threatened by climate change.

A team has hung 32 traps made of green nets, each with bait of rotten fish and fermented bananas. The aim is for them to blend into the forest canopy. Their pungent odor doesn't.

Since last August, a team of biologists and forest rangers has been monitoring the number of butterflies in the Cuyabeno Wildlife Reserve, a park famous for its abundant flora and fauna.

They capture and document the colorful insects, releasing most of them with an identification mark on their wings. Some of them, possibly previously unknown species, are kept for later study.

The results of the team's work, however, have been disappointing.

Butterflies are "bioindicators", living organisms whose well-being provides a measure of the health of the ecosystem around them, and their numbers are dwindling, biologist Maria Fernanda Checa told AFP.

Although the number of species may not have decreased by more than 10%, in terms of absolute numbers of butterflies "the decrease is very significant... perhaps 40/50%," she said.

"That's something we're alarmed about."

- Bioindicators

Under the command of expedition leader Elisa Levy, a team checks the nets for captured butterflies.

They gently hold the insects by their small abdomens and manipulate their legs and wings with tweezers.

Some are bright red and blue, others have what resemble zebra stripes. Some are transparent, like glass.

Around three-quarters of crops producing fruit or seeds for human consumption depend on pollinators, who provide a free service worth billions of dollars.

The UN has warned that 40% of invertebrate pollinators - 

mainly bees and butterflies - are at risk of global extinction, which poses certain risks for humanity.

Butterflies, Checa said, are "very sensitive, even to small changes in the ecosystem" during their short lifespan, from egg to caterpillar to reproductive adult.

Levy explained that tropical plants - unlike plants in regions with different seasons - are not used to extreme climatic variations.

If they don't adapt to a rapidly changing climate, these plants could be lost, along with the butterfly larvae that feed on them.

Ecuador, relatively small but extremely biodiverse, is home to around 4,000 butterfly species, almost the same number as its larger neighbors, Peru and Colombia.

However, in places like Yasuni National Park, next to Cuyabeno, "the rate of discovery of species is slower than the rate of extinction," said Checa.

Paola LÓPEZ

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