Protecting our Pollinators

Bees, so crucial to our food supply, are dying off at alarming rates. CALS researchers are taking a close look at everything from the microbes in their hives to the landscapes they live in to identify in what conditions bees thrive.

People and bees have a long shared history. Honeybees, natives of Europe, were carried to the United States by early settlers to provide honey and wax for candles. As agriculture spread, bees became increasingly important to farmers as pollinators, inadvertently fertilizing plants by moving pollen from male to female plant parts as they collected nectar and pollen for food. Today, more than two-thirds of the world’s crop plants—including many nuts, fruits and vegetables—depend on animal pollination, with bees carrying the bulk of that load.

It’s no surprise that beekeeping has become a big business in the farm-rich Midwest. Wisconsin is one of the top honey-producing states in the country, with more than 60,000 commercial hives. The 2012 state honey crop was valued at $8.87 million, a 31 percent increase over the previous year, likely due in part to the mild winter of 2011–2012.

But other numbers are more troubling. Nationwide, honeybee populations have dropped precipitously in the past decade even as demand for pollination-dependent crops has risen. The unexplained deaths have been attributed to colony collapse disorder (CCD), a mysterious condition in which bees abandon their hives and simply disappear, leaving behind queens, broods and untouched stores of honey and pollen. Annual overwintering losses now average around 30 percent of managed colonies, hitting 31.1 percent this past winter; a decade ago losses were around 15 percent. Native bee species are more challenging to document, but there is some evidence that they are declining as well.

Despite extensive research, CCD has not been linked to any specific trigger. Parasitic mites, fungal infections and other diseases, poor nutrition, pesticide exposure and even climate change all have been implicated, but attempts to elucidate the roles of individual factors have failed to yield conclusive or satisfying answers. Even less is known about native bees and the factors that influence their health.

Poised at the interface of ecology and economy, bees highlight the complexity of human interactions with natural systems. As reports of disappearing pollinators fill the news, researchers at CALS are investigating the many factors at play—biological, environmental, social—to figure out what is happening to our bees, the impacts of our choices as farmers and consumers, and where we can go from here.