Are native bees trying to tell us something? Is anyone listening?
By Emily Loewinger
About a third of the crops we eat are pollinated by insects, and those insects—bees, in particular—are in decline. Between 2015 and 2016, honeybee colonies in the U.S. decreased 8% according to the U.S. Department of Agriculture’s honeybee surveys and reports.
Honeybees, which are from Europe, get the buzz as pollinators, and the bulk of bee research concerns them. Bees that are native to North America also have a significant role in pollinating the environment, though there’s less data about them. Native bees provide more than $3 billion in fruit-pollination services each year in the United States.
Most entomologists agree that native bees are better pollinators than honeybees. Whereas honeybees are focused on nectar, native bees are attracted to flowers solely for their pollen. That makes them more efficient, according to Cornell entomology professor Bryan Danforth. Native bees don’t need the nectar because they don’t make honey. Unlike honeybees, which live in hives, most native bees are solitary and nest underground or in dead plant stalks.
Native bee populations are declining along with honeybee populations—even though native bees are less susceptible to pathogens and disorders that can kill off entire bee colonies, according to the University of Florida Institute of Food and Agricultural Sciences Extension.
“The loss of native pollinators is a huge issue affecting biodiversity, communities’ ecology, and environmental stability,” said Charles Gunnels, Ph.D., wildlife ecologist and Florida Gulf Coast University professor.
Native bees are also more abundant than honeybees, with about 4,000 different species in North America, according to the USDA.
So, what are their populations? And how much have they declined? There are not many records available.
“People don’t really study [native bees] as much because they don’t have a direct perceived utility for people,” Gunnels said.
He said he believes that researchers are more interested in honeybees because they provide a direct economic product—honey.
“Pollination is critical,” Gunnels said, “but the economic benefit (of native bees) is indirect and, therefore, more difficult for people who provide the funding to see and fully appreciate. As a result, researchers pursue projects that will receive funding.”
In 2010, FGCU scientists performed a bee collection study, finding six different native species around campus. FGCU scientists conducted another bee collection in 2018 and found the same number of bee species—a glimmer of hope for the future of native bees, though a much larger study in 2017 shows that nearly one in four native species is imperiled.
Joyce Fassbender, Ph.D., a biology instructor at FGCU, is an entomology expert. She said that bee decline could be the result of a variety of factors. She described colony collapse disorder—where adult worker bees disappear from the hive or become inactive, leaving the queen and juvenile bees to die or relocate as a result.
“They just disappear. It’s not that they’re swarming and leaving,” Fassbender said. “It’s like creepy houses where you walk in and all the dinner is on the table. It’s like that, but with bees.”
Other factors of decline include sickness from parasites—like Varroa mites, which drain the blood of the baby bees and carry harmful bee viruses.
Two other contributors are human-caused: habitat loss as a result of development and exposure to chemicals like pesticides.
Gunnels indicated that there are ways humans can help. To mitigate bee decline, Gunnels suggests planting native flowers and refraining from constantly weeding yards.
“It’s not a hard solution,” Gunnels said, though he also indicated it’s not a large-scale solution. “Sometimes it’s nice to start small.”
Gunnels also suggested reducing the use of pesticides because they can disorient and kill bees.
If pesticide use and land development continue to destroy bee habitats, species of bees are at risk, Gunnels and Fassbender agree.
