Butterflies are one of the most popular insect species in the world. Found on every continent, except Antarctica, their beauty and unique characteristics have catapulted them into mainstream consciousness for centuries. From the Ancient Egyptian wall paintings of 1350 BC to The Very Hungry Caterpillar, butterflies as icons in art and society have long been established as symbols of beauty and gentleness. Butterflies are a fairly common sight for many, but there are those of us whose hearts still whisper, “wow” at the sight of one.
In the past decade, the Monarch butterfly has gained attention because of its dwindling populations. Monarch population declines are largely the result of habitat destruction and climate change. These insects play a critical role in pollination and make many of the foods we eat every day possible. Because of this, it is crucial that we all take action to protect this species – but in order to do so, we must first understand what is threatening them.
Butterflies and a Changing Climate
Butterflies are a favorite of scientists to observe and measure the impacts of global warming. Firstly, they are poikilothermic, which means that they are impacted by short-term events such as weather and long-term events such as climate change. Their daily activities depend on temperature, cloudiness, precipitation, and specific plant (host plant) availability. Therefore, they are a good indicator species for climate change studies.
As global and regional temperatures rise, the range of a butterfly’s habitat can increase. For example, butterflies that once lived in lower latitudinal ranges are now living in more northern areas because temperatures in those areas aren’t as cold as they were in previous years. That means that butterflies can survive in areas where they couldn’t before. That’s a positive impact for butterflies, but it’s not good news for the planet. Why? The expansion of butterfly populations follow warming temperatures and warming temperatures at (and towards) the poles is indicative of global warming. Warmer temperatures at the poles causes sea ice to melt, and that has negative implications for both wildlife and the environment.
The Dwindling Butterfly Population
One impact (of countless direct and indirect impacts) of global warming is that it causes flowers to bloom early. For butterflies that migrate, this is a problem. Butterflies and their host plants have a special relationship (think Monarchs and Milkweed). The host plant provides its butterfly with food, perhaps a place to lay its eggs and assists in other life cycle functions; the butterfly pollinates the host plant. If a flower blooms earlier than its specific butterfly arrives, there’s a chance that when its butterfly finally does arrive, the flower will be past its blooming period. Therefore, neither the butterfly nor the flower will be able to engage in this mutually beneficial behavior. The butterfly doesn’t eat, and the flower doesn’t get pollinated.
Similarly, this problem impacts species of butterflies that overwinter (don’t migrate) in their breeding ranges. In some cases, these butterflies can emerge from hibernation earlier than their host flower blooms, and results in the same outcome.
This problem might also have an effect on the host plants. Plants can have principal pollinators, just like insects can have host plants. That means that there’s a special insect out there for a specific plant that gets the job done in the best way possible. Some plants are self-pollinating, meaning that they do not rely on insects to help them reproduce, but others that depend on insects for reproduction might have trouble if their principal pollinator doesn’t arrive on time for their date.
Certain species of butterflies have been forced to use other, less preferable plants to fulfill their life cycle functions. This has caused some butterflies like the UK’s Brown Argus to be less fit as a result of decreased egg laying. Laying fewer eggs means less butterflies, less butterflies means less genetic variety, less genetic variety means that the species will have difficulty adapting to environmental challenges.
Impact on the Food Chain
Butterflies play a large part in food webs and food chains – at all stages of their lifecycle they can be a food item for other animals. When the flora or fauna on the lower part of a food web or food chain is impacted by climate change, the fauna on the higher end can also be impacted. In a food chain each subsequent level depends on the previous level, therefore, a disruption at the lowest level can cause problems that echo throughout the chain. Nearly two-thirds of all invertebrates can be connected back to the butterfly on the food chain. If animals cannot adapt to these changes by finding other food sources or other organisms to provide specific services (like pollination), they could be at risk for population decline – there is a reason that they call it the “Butterfly Effect.”
The impact on butterfly loss is felt all the way up to humans. According to the U.S. Department of Agriculture, “Some scientists estimate that one out of every three bites of food we eat exists because of animal pollinators like bees, butterflies and moths, birds and bats, and beetles and other insects.” As bee populations dwindle as a result of rampant pesticide use, bats decline with habitat loss, and butterfly populations wane, we’re left with few options to turn to. Our entire food system hinges on the single job of pollinators so it is in all of our best interest to actively work to restore these important pollinator species.
How You Can Help
There are many daily actions that you can take to help the butterfly population recover. While changing the course of global climate change might be daunting, you can take action through your food choices. The livestock system is responsible for more greenhouse gas emissions than any other industry, so by cutting down on the amount of meat and dairy you consume – or eliminating it entirely, you can lower your personal participation in this destructive industry. By simply leaving meat off your plate, you can halve your carbon footprint. Join One Green Planet’s #EatForThePlanet campaign to learn more.
You can also take direct actions to help butterflies by planting native milkweed in your area. Milkweed is the primary food source of Monarchs and other butterfly species. Check out these other resources to learn how you can help these struggling pollinators:
- 10 Ways to Save Pollinators and Protect Our Food Supply
- 5 Ways To Turn Your Garden Into A Haven For Wildlife
- 7 Ways to Attract More Butterflies to Your Garden (and Save Them From Extinction)
We need butterflies more than they need us, so it is more important than ever that we all do our part to save this species.
Lead image source: Charlesjsharp/Wikimedia Commons