The scientific community is now fairly certain that pesticides like neonicotinoids are the leading cause behind a drastic decline in honeybee populations first noticed nearly a decade ago. However, how exactly this was happening remained a mystery. Now, researchers believe they have determined how a pair of pesticides are stripping essential pollinators of their energy.

According to past research, what has been driving a striking decline in bee populations first noticed in 2006 has been colony collapse disorder (CCD), a mysterious illness among pollinators that causes them to wake up during wintering months and leave their hive, only to die in unforgiving temperatures soon after. CCD has also been caused by bees simply not returning to their hive in the middle of pollination season, an equally mysterious occurrence.

While natural parasite invasion has been seen as one cause for CCD, a whole host of recent studies has linked pesticides - namely neonicotinoids (neonics) - to most instances of CCD in the United States.

In learning this, US Fish and Wildlife Service and the National Park Service has begun to phase out the use of neonics. Some big name garden retailers like BJ's Wholesale have also sworn off the use of these harmful pesticides.

However, even in the wake of all this action against neonics, the scientific community has remained unsure exactly how it is causing CCD. A new study published in the journal Environmental Toxicology and Chemistry might have the answer.

The study details how Daniel Nicodemo, an expert of ecology and beekeeping at the Universidade Estadual Paulista, analyzed the biological effects neonics and pyrazoles - another type of potentially harmful insecticide - have on bees.

According to the study, Nicodemo and his co-authors paid special attention to the function of mitochondria, the "power plants" of a cell, in the head and thoraces of Africanized honeybees.

"Similar to a plane, honeybees require clean fuel in order to fly," Nicodemo said in a statement.

He claims what these pesticides are doing is essentially dirtying that fuel, sullying energy synthesis so that honeybees find themselves functioning at half strength, unable to collect enough energy for a full wintering, and hampering their ability to forage.