In the past two decades, American bumblebee populations have dropped by 90%.
Pesticides, development and climate change are poisoning this bee and destroying its habitat. If the decline of bees like this native pollinator isn't halted, plants and ecosystems across the country will suffer.
Where did the American bumblebees go?
At one point, the American bumblebee occupied one of the largest geographic ranges of all bumblebee species in North America.
Now, a range that once stretched from coast to coast has been reduced to a fraction of its former extent. In the Midwest and Southeast, as many as 1 in every 2 American bumblebees has disappeared. In other states, that number rises dramatically — in New York, as many as 99% of the bumblebees have disappeared. And in eight states, the bee has vanished entirely.
We know what's driving this collapse. Climate change, disease and habitat loss have all been putting increasing pressure on the bumblebees in recent years.
One factor in particular stands out: pesticides. The states that saw the greatest decline in these bees' numbers were also the ones that had the largest increase in their uses of pesticides, including a class of pesticides known as neonicotinoids, or "neonics" for short.
These pesticides weaken the bees' immune systems, disrupt their ability to communicate and diminish their ability to find and return to their homes.
In one event, anywhere from 45,000 to 100,000 American bumblebees from hundreds of different colonies died after coming into contact with trees that had been treated with neonics outside an Oregon shopping mall. It was the largest number of bumblebees killed by pesticides ever recorded in North America — and the study's authors note that many other mass death events across the country likely go unrecorded.
Now it seems these deaths are adding up.
Ecosystems need their bees
Mass deaths of bumblebees may go unrecorded by humans, but they certainly don't go unnoticed by the ecosystems that rely on these vital pollinators.
Bees play an important role in many ecosystems' food webs, providing food for birds and reptiles and helping the growth of a number of plants.
American bumblebees also play an important role in pollinating a range of crops and wildflowers. Along with the other bumblebees, honey bees and solitary native bees, these pollinators are responsible for helping a tremendous number of plants reproduce across the continent — including many of the crops that humans rely on for food.
Out of the 100 crops that supply 90% of the world's food, 71 are pollinated by bees.
The factors that are driving the decline of the American bumblebee are largely the same as those driving the collapse of many other species of bee. If the American bumblebee receives protections under the Endangered Species Act, many of those other pollinators will also likely benefit.
But if nothing changes, the collapse of these bee species will have devastating consequences that will ripple across our country's food webs and ecosystems.
The time to act is now.