People around the country are noticing. Bugs no longer coat windshields, butterfly gardens take more care with fewer butterfly sightings, and bee colonies are collapsing! Globally, biodiversity is in peril. A recent report from an international team of scientists warns that up to one million species may go extinct within the next few decades.
Despite these warnings, there is one group that is essential to our lives but rarely gets the conservation attention it deserves - insects! Insects are the most diverse group of animals on Earth, with over 5.5 million known species found on every continent. The decline in insect populations over the last few decades has recently come into the spotlight, especially considering the devastating consequences for humans. Insects are responsible for keeping our food systems working via pollination. They help return nutrients to the soil. And they play an integral role in the food chain for every ecosystem.
Butterflies are one of the best-known groups of insects. From stickers to hair clips, the butterfly is ubiquitous in society. But even the beautiful butterfly is not immune from the fate of so many fellow insects. A recent study by Dr. Adrian Wepprich and colleagues looked at the status of 81 butterfly species in Ohio over the course of 20 years. They found that the abundance of butterflies decreased by about 2% per year, for a total of 33% over 20 years. This is alarming because butterflies are the best-monitored of all insects. That is, they are the best indicator of the threat to the rest of the world’s millions of insect species.
What’s happening to all these insects? In the case of butterflies, threats like climate change, habitat degradation, and poor agricultural practices are driving their demise. Some changes are favoring one species of butterfly over another to drive diversity loss. Habitat loss - particularly the loss of milkweed plants - is largely responsible for the decline of monarch butterflies. The destruction of milkweed has contributed to the 86% plummet in the Western monarch population since late 2017. Scientists now fear that the monarch could go extinct within 20 years.
Defenders of Wildlife works to protect insects across the country. One way is by ensuring that Congress continues to support conservation like they did with the recent Farm Bill that maintains conservation funding, programs and provisions that benefit both landowners and pollinators — while preserving existing environmental laws. Farm Bill programs like the Environmental Quality Incentives Program, Conservation Stewardship Program (CSP), and Conservation Reserve Program (CRP) assist farmers with planting milkweed and other practices that benefit pollinators while keeping working lands working and strengthening rural economies.
Defenders also promotes proper consultation with the Fish and Wildlife and National Marine Fisheries Services to ensure that activities like pesticide application or development don’t jeopardize endangered or threatened pollinators or their habitats.
In California, we are fighting to list four species of native bumble bees — western bumble bee, Franklin’s bumble bee, Crotch’s bumble bee, and the Suckley cuckoo bumble bee — as Endangered under California’s Endangered Species Act because they are in steep decline and are found in only a few areas within their historic range.
The loss of biodiversity is devastating to humans and wildlife alike. Without diverse environments, we lose the stability of healthy ecosystems that help us maintain our way of life. From supporting our economies to providing clean water to keeping our food systems intact, maintaining biodiversity helps all species thrive. And though we will happily see butterflies in sticker form, we need butterflies (and all other insects!) in the wild.
- Díaz, S., Settele, J., Brondízio, E., Ngo, H., Guèze, M., Agard, J., ... & Chan, K. (2019). Summary for policymakers of the global assessment report on biodiversity and ecosystem services of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services.
- Wepprich, T., Adrion, J., Ries, L., Wiedmann, J., & Haddad, N. (2019). Butterfly abundance declines over 20 years of systematic monitoring in Ohio, USA. BioRxiv, 613786.
- Schultz, C. B., Brown, L. M., Pelton, E., & Crone, E. E. (2017). Citizen science monitoring demonstrates dramatic declines of monarch butterflies in western North America. Biological Conservation, 214, 343-346.