Jaime Rojo The photographer’s images of Mexican butterflies in the snow

A carpet of Monarch Butterflies covers the forest floor of El Rosario Butterfly Sanctuary after a snow storm that hit the state of Michoacán in Mexico on March 2015.  On March 8th and 9th of 2016 a strong snow storm hit the mountains of Central Mexico creating havoc in the wintering colonies of Monarch Butterflies just when they were starting their migration back to U.S.A. and Canada. Monarch butterflies are surprisingly resilient and they can survive several days in below zero temperatures as long as they remain dry. Deforestation reduces the shelter for the butterflies making them more vulnerable to the weather elements. And although illegal logging has been curbed thanks to the conservation efforts in Mexico, climate change is creating an increase of these unusual weather events which represent one of the biggest challenges for these insects during their hibernation period.

Jaime Rojo is a Spanish conservation photographer living in Mexico. During an unexpectedly heavy storm in March, he went to the El Rosario Butterfly Sanctuary and found thousands of Monarch butterflies lying in the snow. These endangered species are emblematic of this region and are known for undertaking the longest insect migration – each year they fly from the northern United States and Canada south as far as Florida and Mexico.

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I have been working with Monarch butterflies for over ten years now, and could name a thousand reasons why I photograph them. First of all, they have one of the most well-known migrations in the animal world, and as a wildlife spectacle they’re one of the most impressive things to watch. I’m talking about millions of butterflies flying around at the same time.

These large concentrations of animals have a very important meaning for conservation. They’re an iconic species of this region in Mexico, but at the same time, they’re very endangered. Do not get confused by the optical illusion of seeing so many butterflies in my photos. Even though they are resilient, they are currently very threatened.

As always in the environment, the problems causing it are three-dimensional. One of them is the use of the pro-spectrum pesticides that kill the milkweed. This is a kind of grass on which these butterflies depend for their migration. If there is no milkweed, they can’t find the energy they need to make their epic journey.

But also unusual weather conditions (caused by climate change) are an important factor. The time I took this picture, there was an unusually strong storm. We have snow in those woods, but never in March. More than 90 percent of the population of Monarchs gathers in these forests. So if something unusual happens, the risk of losing a species is really high. You can wipe out an entire population with a storm.

When I saw these storms coming to the mountains, I immediately thought about the butterflies. I requested special access to the park very urgently, but I had to wait 48 hours until they allowed me to go in and document the story.

Once I was in the region where the butterflies gather, it was very difficult to capture them. The ground was covered with Monarchs. You cannot step on them, so with help of people of the reserve, we made a little trail, moving one butterfly after the other. I wanted to get an image that could summarize the whole catastrophe the colony was experiencing.

This being said, I don’t think any of those butterflies in the winning picture are dead. They are frozen, but they can survive up to three days in freezing conditions as long as they remain dry. The moment they die, they lose water and they start to shrink. But if the sun hits them and they warm up before the snow melts, they are able to walk up a trunk or even fly away.

As a conservation photographer, it’s always tricky to find a balance between beautiful, emotional and inspirational stories and the harsh and sad stories that grab your heart. I think we are immensely privileged but we also have great responsibility, because we are showing the rest of the world what is happening on the planet. We are here to amplify the voice of nature by using the emotion a very strong image can create.