Seeds coated with pesticides are killing Colorado’s bees

Bees are fascinating creatures that have been part of human culture for thousands of years; for example, the ancient Greeks viewed them as symbols of immortality. In 19th-century England, there was a tradition known as “telling the bees” where beekeepers would inform their bees of significant events like births, deaths, marriages, or long journeys.

Perhaps this connection we feel with bees stems from a deeper understanding of their critical role in nature. Bees and other beneficial insects shape our environment – they pollinate the crops that feed us, recycle nutrients, and provide a vital food source for countless other species. Without them, the natural balance that sustains all life would unravel.

Whatever the reason, when bees are in trouble, people and some lawmakers are willing to respond.

Bees are disappearing across Colorado

The American bumblebee was once a common site across Colorado, buzzing from flower to flower and playing a critical role in pollinating wildflowers and crops. Now, its population has declined so sharply that it has been under review for protection under the Endangered Species Act (ESA). 

The U.S. Fish & Wildlife Service has petitioned for the Southern Plains bumblebee, another Colorado native, to be protected under the ESA. It also has reviewed the Western bumblebee, Suckley bumblebee and Variable cuckoo bumblebee.

The western bumblebee has declined 72% in the Southern Rocky Mountains, and future population trends are grim.

A report from the Proceedings of National Academy Sciences finds, in the western United States, “By the 2050s, [the] most optimistic scenario predicts occupancy declines in almost half of [the] ecoregions; more severe scenarios predict declines in all ecoregions ranging from 51 to 97%” for western bumble bees.”

Source: https://www.pnas.org/doi/10.1073/pnas.2211223120

Overall, one in five Colorado bumblebee species are at risk of extinction, and other insects are also declining.

Neonics are everywhere

Colorado’s diverse habitats are home to approximately 1,000 species of bees—about 25% of North America’s bee population. However, beneficial insect populations are declining across Colorado, and scientists are trying to determine the reasons behind this trend. Potential causes include disease, climate change, habitat loss, and the use of toxic pesticides, in particular a class known as neonics.

Overall 100 million acres of cropland in the US are exposed to neonic pesticides, which is about the size of the state of California. The EPA estimates that 70-80% of corn, soybeans and cotton seeds are treated. Usage of neonicotinoids soared with the practice of coating the pesticides onto seeds. Farmers often use these toxic seeds even without a pest problem because uncoated seeds are not available.

Neonics on seeds don’t stay put, and they stick around for a long time

About 5% of neonicotinoids remain on the plant.

During planting, the pesticide can rub off, creating a cloud of toxic dust. Wind may carry this dust onto nearby bee habitats, posing a lethal risk to bees that come into contact with it. The pesticide also leaches from the seed, accumulating in the soil and contaminating nearby waterways.

Even when neonicotinoids do stay on the plant, the chemical is absorbed into every part — including the stem, leaves, flowers, pollen, and fruit — turning the entire plant into a potential hazard for bees.

These pesticides can remain in the soil for months to years, depending on the specific chemical, environmental conditions, and soil type. They can also accumulate, leading to higher concentrations over time.

Evidence is mounting that other animals are harmed

Neonics are insecticides—meaning they’re designed to kill insects. But it’s not just insects that are harmed. Research has shown that even a single neonic-coated corn seed can be deadly to a songbird.

In Minnesota, a study of white-tail deer found increasing neonic contamination in their spleens, and research from South Dakota linked neonics to fawn mortalities. We need more research to fully understand the impacts on deer and the predators that consume them—including us.

Neonics aren’t effective

You might think someone has crunched the numbers, carefully weighing the risks to bees and birds against the need to feed a hungry nation.

But that hasn’t happened—and if it did, chances are the threats to bees would far outweigh the supposed benefits. Why? A compilation of research shows only a limited, if any, increase in crop yields. For example, just 12% of corn trials showed a production increase. Results like that don’t come close to justifying the added costs of treated seeds.

Neonics aren’t regulated as pesticides

The EPA doesn’t regulate neonic-coated seeds as pesticides, thanks to a loophole in federal law. Because these seeds are considered “treated articles,” they’re not subject to the same rules and oversight as other pesticide applications. This means they skip important safety checks and environmental reviews, even though the pesticide coating is designed to kill insects like any other insecticide.

Colorado can lead and build on previous success

We’ve seen success in Colorado before. In 2023, we won a major victory for pollinators when the state banned neonic pesticides from retail shelves. This new law, which went into effect on July 1, means that consumers won’t be buying neonics off the shelves anymore—only licensed pesticide dealers can sell them. It’s a huge step for our bees, butterflies, and other essential pollinators.

Building on that success, Colorado needs to look at neonic-coated seeds. The toxic pesticide on seeds is threatening our bees, birds, and entire ecosystems. Colorado needs to lead the way and take the next step—let’s push to restrict these dangerous pesticide-laced seeds. The health of our environment, our food systems, and our future depends on it.