There are at least 18,682 species of butterflies in the world. Of these, 3,280 species are in Brazil. The Iguaçu National Park serves as a shelter for about 800 species, of which only 257 have been properly identified. The Argentine researcher Ezequiel Núñez Bustos has cataloged 653 species for the Iguazú National Park, in Argentina.

But there is still work to be done, as some areas of the park were left out of research. At this point, you may be asking: these numbers, for the Iguaçu/Iguazú national parks, are too much or too little?

They are significant. Remember that European continent as a whole has 244 species of butterflies.

It is increasingly common for travelers to mention the butterflies of the Iguaçu Falls as one of the great attractions of the region. There are comments from visitors on sites like Trip Advisor, in which they state that the butterflies alone would be reason enough for the creation of National Parks that bear the name of the Iguaçu River, one on each side of the border.

Those who visit the Iguaçu/Iguazú national parks in the summer, autumn or spring months will have the company of countless butterflies. During winter, the number decreases because of the cold, but some species are still there. Butterflies of various shades of yellow fly over the stretch of the highway BR-469 inside the Iguaçu National Park. Other species prefer the trails that allow panoramic views of the Falls. Two of the most spotted species in this section are the Butterfly 88, the Diathreas, and their closest relatives, the Callicores. Understanding and differentiating the two species is not an easy task. But one can always try. The first tip is to note that the 88 may be accompanied by other numbers like 89, 98, 69 and 96. The pattern of the wings of the Callicores contains dots that form different shapes. But, for both, the patterns appear on the borders of the wings, when the butterflies are resting with their wings closed. When they relax and open their wings, the look is totally different: on the 88, for example, a matte black color prevails, with metallic dark green stripes at the top of the wings and the same metallic blue stripes at the bottom of the wings.

Borboleta 88

An 88 showing details of the strong colors on the inside of the wings and the patterns that make up the 88 on the outside  

Many other species of butterflies are observed along the trails of the Falls, both on the Brazilian and on the Argentine side. Many of them land on the visitor’s arm, hand or shoulder. They may also choose to land on backpacks and on other visitors' belongings. The reason for the choice is the salt in the visitors' sweat.

In open places along roads or trails, for instance, near the reception area of the Macuco tour, it is possible to find puddles of water with hundreds of butterflies of various species, especially the yellow Phoebis sennae and Anteo clorinde. These butterflies go by several names in Brazil, like flock butterfly or gem butterfly. On the Argentine side of the Falls, tourists walk on foot along a path that borders the train track that connects the Central Station to the Devil’s Throat Station. There are several kilometers of butterfly watching opportunities. Some puddles of water rich in clay with a high concentration of mineral salt are shared by gems butterflies and their colleagues Heraclides astyalus – with the popular English name “broad-banded swallowtail”.

Butterflies in the Birds Park

Famous and recognized as a center specialized in birds of the Atlantic Forest, the Birds Park (Parque das Aves) also has a butterfly garden. Of the 800 species of butterflies estimated for the Iguaçu/Iguazú National Parks, 42 are found in the Birds Park’s butterfly garden.

A visit to the Birds Park’s butterfly garden is an important tool for environmental education, for entertainment and can also be seen as a therapy against the stress the visitors leave outside the park. Within the space, the butterflies fly and share the space with different species of hummingbirds.

In a laboratory dedicated to the reproduction of butterfly species, a team collects eggs from the different species that reproduce there. The eggs are tiny, some a little bigger than a grain of sand. Some of them are kept in a protected area out of the visitor's reach. Isolation is necessary for biological protection against viruses, bacteria and fungi.

In one of the laboratory rooms there is a real butterfly maternity, with caterpillars (larvae) in different stages of growth. Developing caterpillars spend their time eating to obtain and store the energy necessary for the immobilization stage, for the generation of the cocoon.

“The body of this one is getting ready. The skin starts changing color and becomes transparent”, explained biologist Agnis Ramos. The next step for the caterpillar is to choose a safe place to cling, hang and fall asleep. That sleep will accompany the process of giving up the caterpillar figure and betting that existence inside a cocoon for a certain time will lead to a rebirth as a butterfly.

Within the cocoon, the caterpillar body will change to a liquid state in the middle of which the butterfly body begins to form. One day, it's time to be reborn. The butterfly begins to come out of the cocoon where it was sheltered. Once out of it, the new being will discover its legs, wings, antennae and proboscis – a small trunk that it will use to feed itself. None of this existed in the previous caterpillar body. Finally, it's time to spread its wings. It will be the first time that it will see its own wings. “But the butterfly is not able to fly immediately”, explained the biologist, pointing to a Caligo brasiliensis, known by the name Owl Butterfly, which patiently waited, without moving for its wings to dry. “It takes four hours to dry its wings”, explained Agnis.           

One of the species in the butterfly garden is Morpho epistrophus, a large butterfly, which spends 11 months in the caterpillar stage.

Despite living in the forest, each butterfly has its own diet. “Morpho eats maquerium”, explains the biologist. The three varieties of caligo like leaves of plants of the banana and heliconia family. “The Brazilian Monarch feeds on the ascleplia tree”, highlighted Agnis, adding that most butterfly lovers do not know that Brazil also has monarch butterflies. 

Borboleta Papilo Thoas

Go ahead! You can already identify your first “swallowtail butterfly”. (Papilio thoas)

From the three subfamilies above, you can take two off your wish list when watching butterflies in the Iguaçu Falls area: the baroniinae is restricted to a small region in Mexico and the Parnassinae are butterflies of altitude in cold climate in Asia.

Preservation

The Iguaçu/Iguazú National Parks, with emphasis on the area surrounding the Iguaçu Falls, are asserting themselves as one of the best places in the world for the butterflies watching. With the expansion of urbanism and agricultural activities, the vital space needed for butterflies is getting smaller. There is also the problem that butterflies, especially during the caterpillar stage, are considered plagues for agriculture. The possibility of seeing them in their natural environment, as well as the opportunity of interacting with the butterflies, as in the cases when they land on visitors, is part of the great adventure. Take pictures of them, love them, have fun. However, avoid touching or picking them up. Because they are fragile, touching them can cause irreversible damage. Also, protecting them is one of the reasons for the existence of the Iguaçu/Iguazú National Parks, both part of the list of World Natural Heritage, promoted by Unesco and part of a treaty involving more than 120 countries.