My children love insects, especially butterflies. Their favorite butterfly is quite possibly the most popular of all butterflies, the Monarch butterfly. For the last three years, we have participated in a Monarch Butterfly preservation program in collaboration with the Nature Center of Cape May, NJ. We plant milkweed, the only food that Monarch caterpillars eat, around our house. Soon enough our plants are heavy with hungry, yellow, white, and black caterpillars. When the caterpillars are close to being ready to enter the chrysalis phase we move them to an inside hatching tent. It’s always a fun adventure to go around the yard and see if we can find any chrysalises to move inside also. Once the butterflies have hatched we log some data and tag each one with a specially designed sticker. The stickers are used to help scientist track the migration of Monarch butterflies. Then, in October we head to the Nature Center for a Monarch butterfly festival, an event that raises awareness of these fascinating creatures and funds to continue Monarch tagging.
We will definitely continue studying Monarchs at home, but with the current social state of the world, we may not be able to make it to the festival this year. I was so pleased to find an amazing program by PBS to show my kids a new view of Monarch butterflies, a rarely seen view. On May 6, 2020 PBS Nature aired a special called Spy In The Wild, an up close view of a Monarch winter resting ground. The whole series focuses on using camera equipped spy creatures to observe animals like orangutans, tortoises, and hippos in their natural environment. To be able to observe the butterflies a special drone was designed by John Downer Productions, the production company behind the documentary.
Drones are ideal tools to use as spy gadgets in the animal world as they can get up close to wildlife in a way humans can’t. If properly disguised, a drone can easily infiltrate a wildlife habitat. However, using drones around wildlife can also be very tricky. There are laws that prevent drones coming within a certain range of some creatures as the sound of the drone can be alarming and stress out the creatures. Because Monarch make their winter resting grounds in remote Mexican forests and are extremely sensitive to outside forces, like a camera crew, getting detailed footage of them has been difficult. Phil Dalton from John Downer Productions knew they had to come up with an ingenious tool to meet the challenge of documenting a Monarch forest without disturbing the butterflies.
“We wanted to make a small spy creature that could explore and maneuver through a forest and film one of the most fragile creatures in the entire series, Monarch butterflies,” Phil said. “We knew hummingbirds share their habitat and so this was our inspiration. The goal was to make a hummingbird to scale, about 20 centimeters [8 inches] from head-to-tail, hover in all directions, be as quiet as possible and have no exposed moving parts, as well as carry a 4K camera.” Butterflies and hummingbirds share habitats and feed from the same sources. The both sip nectar from flowers. A hummingbird drone hovering around millions of resting butterflies would be no different that a natural hummingbird in the environment. “After many prototypes, we managed to make spy hummingbird, weighing just 70 grams,” Phil went on to say. “It could hover just like the real thing. It was also totally harmless to the butterflies with shields to protect the butterflies from coming into contact with moving parts. The butterflies could even land safely on [the] spy hummingbird’s wings.”
Every year millions of Monarch butterflies travel thousands of miles, returning to the same grove of trees in the Mexican Neovolcanic Axis. There is much that is known about the life cycle of the Monarch butterfly. One such interesting fact is that the butterflies that make it to Mexico are of the fourth generation born each season and they are genetically programed to live long enough to make the journey, a longer lifespan than the three generations before it. Another fact that baffles scientist is that the butterflies that make it to Mexico somehow know how to return to the trees of their ancestors without having any type of communication with another living creature that had made the same journey.
Why the butterflies return to the same spot is still a mystery, but for the first time, a team was able to send in a camera to get up close to this natural phenomenon. The hummingbird drone hovered around the trees, whose branches were drooping to the ground from the weight of the butterflies. All was calm and still because the drone is perfectly disguised to be a natural part of the environment. Every now and then a butterfly opened and closed it’s orange, black, and white wings. Then as the temperatures start to rise, a few butterflies fluttered off from the branches, some landing atop of the drone. Then within moments, as if of a single mind, all of the millions of butterflies awoken and began to swarm off from the branches, swirling into the air around them, preparing to begin the generational journey back north. The drone’s camera was able to capture all of this up close, inside of the swarm. The scene looked like a fuzzy cloud, filled with so many flapping wings that they made a low roar through the forest.
Because the swarm was so immense, it was hard to discern what was being seen when they first took flight. That is until the 4K camera hidden in the drone revealed slow motion footage of what was happening around it. Slowly, a few butterflies came into focus, looking like they were almost dancing through the air. Then the drone focused in on one single butterfly, a male as denoted by the small black spot on each hind wing. The wings flap open and closed in a wave like motion, as it’s abdomen flexes to help give it power. Filming a Monarch butterfly swarm like this has never been so successful. As Phil said, “The results were sensational, filming the migrating swarms through the forest, wingtip to wingtip.” Hopefully this will provide researchers with some more insight to the life cycle of the Monarch butterfly and how to better protect it. But as I said to my kids, it’s possible that one of the millions of butterflies filmed with the hummingbird drone also had a small tracking sticker on it’s hind wing because it came from their backyard.