WWF’s Monica Echeverria has escorted scientists and television crews to the monarch butterflies’ wintering grounds twice. She spoke with WWF Travel about her remarkable experiences.
WWF Travel: Our tour takes place in February. Can you describe what our travelers will see at that time?
Monica Echeverria: The first time I went to see the monarchs was at the end of January. At this time, the butterflies are often sleeping, but some of them wake up when the sun hits them and warms their wings. Then they fly to ponds or puddles to go take a drink of water and return to the trees.
The second time was at the beginning of March, just when they started to awake and fly all over the place. One of the most impressive scenes was when, we were driving on a highway and all of a sudden we noticed a colony of butterflies flying down the mountain. It was like a huge column of black and orange, all following each other. You think they are going to crash into you, but they don’t. All the cars stopped, and we watched for an hour.
WWF: What are the conditions like?
ME: The butterflies are found in high-altitude areas. Often you will have to hike 1 or 1 ½ hours through oak, oyamel and pine forests to get the sanctuaries.
WWF: Do the branches on the trees in the forests really bend from the weight of all the butterflies?
ME: They do! It’s like tree branches in the winter, hanging from the weight of all the snow. Each weighs less than half an ounce. There are thousands on each branch. You don’t even see the trunk or branches of the trees—not one single spot is left. It’s all black and orange.
WWF: Why do the butterflies come here?
ME: As with some other species, the monarchs migrate to avoid the strong winters in Canada and the United States, finding the right temperature to hibernate in these forests. What we don’t know is how each year one generation for every four or five generations comes back to the same mountains. We don’t know how they find their way back to the same area. It’s a big mystery.
WWF: How does a small butterfly have the energy to make such a long trip?
ME: The generation that migrates is physically different from the other generations. For example, during their larval phase they don’t develop sexually, but instead they accumulate fatty deposits, gaining calories to prepare for the trip. They use those lipids for energy to fly all the way to Mexico. When they arrive, they sleep to gain weight and take in sun exposure. During this time they also become sexually mature. When they finally wake up, they go like crazy! You see them mating everywhere.
WWF: What should travelers do to prepare for this trip?
ME: Expect a lot of walking. Because of the high altitude and hills, you should be in good shape. Make sure to wear good hiking boots, and bring lots of water. It can get cold, so bring gloves and a hat and a warm jacket.