Landscape, Art, and Ecology

Butterflies: Small Bodies, Huge Impact

At first glance, because of their tiny size and frailness, one might not truly grasp the significance of these four-winged beings. They are not only beautiful to look at but also integral to ecosystems and have significant environmental impacts. There are more than 20,000 species of butterflies and they all have an essential role in the pollination of plants.⁵ They feed on the nectar inside of flowers and rub up against the pollen. This contains genetic material that becomes attached to the butterfly and is later dropped into other flowers they encounter. This pollen lands on the female part of another flower of the plant, allowing reproduction. These pollinators are a main source in growing fruits and vegetables. As stated by Environmental Science Writer, Keira Gaynor,

We can thank pollinators like butterflies for food like our fruits and vegetables. They are responsible for one in every three bites of food we consume and contribute over 200 billion dollars to the food economy worldwide.⁶

What is even more astonishing about these pollinating creatures is that they travel long distances, and the pollen attached to their bodies moves further than that of other pollinators. This helps plants and our earth by promoting genetic variation and disease resistance.⁷ Furthermore, butterflies help keep other organisms in check by consuming them in various stages of their life. In the larval, or caterpillar stage, they eat the leaves of host plants and utilize them as energy while the larvae grow. They also consume flowers or seed pods, and in turn, they help the plants lose leaves prior to autumn, or help keep specific plant species from spreading out of control. Typically, butterflies are very particular to the type of plant in which they feed such as the Monarch butterfly who only gravitate towards milkweed during their caterpillar stage. However, some adult butterfly species eat rotting fruit, carrions, or other animal excrement, thus assisting in eliminating waste from our environment.

Ecosystems depend upon various animals, insects, and plants to maintain balance and thrive. Scientists use the presence or absence of butterflies as a predictor of whether an ecosystem is healthy.⁸ Both the adult and larval forms are sensitive to various pesticides. Climate change also effect butterflies since temperature variations and rainfall amounts may alter migration decisions and timing. Loss or devastation of their habitat – such as, losing the wide range they cover because of construction or defoliation - increases predation and reduces their opportunity of metamorphosis. Therefore, ecologists study butterfly behavior, their population numbers, and migration patterns to help determine the impact of these environmental issues. They can often be the first indicators that our environments are facing problems.

The unfortunate decline of the monarch butterflies has been a troubling indicator since the 1980s. The International Union for Conservation of Nature added the migratory monarch butterfly to its “Red List of Threatened Species” as endangered on December 30, 2021. Then, on September 27, 2023, they announced that the status would be changed from “endangered” to “vulnerable” starting December 11, 2023.⁹ This alteration was due to a shift in the data used to evaluate the monarchs, not a change in its recent population. Deforestation at the overwintering site is the immediate threat, but not the only one. Within the U.S, the extensive use of pesticide-tolerant, genetically modified crops has dramatically reduced the supply of milkweed available for the monarchs.¹⁰ This is a problem because this species will not lay their eggs on anything else, and it is a vital food source for them.  Over the longer term, climate change is an even bigger threat. Drought along the monarch’s flying trail is now commonplace and the lack of nectar sources exacerbates the odds of their survival during their journey. Meanwhile, warmer winters are gradually driving monarchs to higher elevations in Mexico (main destination) and other sites because the butterflies can only perch successfully if temperatures that are favorable. Nevertheless, they are already near the mountaintops. Therefore, in another couple of decades, there will be nowhere for them to move up to. It is also unclear whether they can be induced to go somewhere else. Optimistically speaking, butterflies are tough beings. They have dealt with global change during their roughly 1.5 million years living on earth.¹¹ Still, mankind continues to throw challenges at them as they try and adapt. Unquestionably, positive intervention by people is crucial for the survival of monarchs and other butterfly species. Organizations such as Monarch Joint Venture, National Wildlife Federation, and Xerces Society (just to name a few) are dedicated to conserving monarch butterflies as well as other native insect pollinators. They have made a tremendous impact, but restoring the habitat these remarkable creatures is mission that must be done worldwide. It is an obligation we must all uphold.