Scientists Point to Pesticides as Culprit in Honeybee Die-Offs

photo by Lisa Kleger

For over a decade an international debate has raged over the cause of the global decline of honeybees. The implications of Colony Collapse Disorder (CCD), the mysterious disease decimating honeybee populations, extend far past the beekeeping industry.  The honeybee is essential to our entire agricultural system—it is the master pollinator (responsible for some 1/3 of our diet) and if driven to extinction, our entire ecological system will be in jeopardy. Beekeepers and researchers have long been concerned that pesticides are actually at the root of CCD—and at the center of the debate is a neonicotinoid pesticide (or “neonic”) called clothianidin.

Many European countries have taken action to limit or ban the chemical, but the United States has been slow to follow suit. In 1997, noticing the rapid decline of their bees (and prior to the coining of the term CCD), beekeepers in France demanded that Bayer’s imidacloprid pesticide Gauchobe investigated (see notes on the first study, below, for more info on imidacloprid). It was partially banned in 1999 ; in 2008, France and Germany finally completely rejected the use of clothianidin.  In 2009 Italy also instated a ban. Since then, there have been reports that colonies are recovering in areas where neonicotinoids were banned.

However, on this side of the pond things are more complicated and controversial. In 2003 U.S. farms began using systemic pesticides called neonicotinoids, including clothianidin and imidacloprid. Almost immediately, beekeepers and scientists noticed that bees contracted out to monoculture farms using the pesticides often appeared confused and disoriented. This behavior led to suspicions that the accumulation of pesticides in the honeybees might be acting as neurotoxins, interfering with their nervous or immune systems. Unfortunately, the EPA approved the use of clothianidin even when its own scientists expressed concerns. After giving clothianidin “conditional registration” in 2003, the EPA asked Bayer (the company that makes the pesticide) to study its effects on honeybees.  Despite finding Bayer’s study inadequate, in 2010 the EPA granted clothianidin full registration.

In just the past month, three separate independent studies have been released connecting bee die-offs and neonicotinoids. Here is a brief summary of what they found:

  1. Neonicotinoid Pesticide Reduces Bumble Bee Colony Growth and Queen Production.” British researchers found that when colonies are exposed to imidacloprid, another neonic pesticide, their growth rates suffered tremendously and the rate at which they produced queen bees declined by 85 percent. Imidacloprid is very close in chemical structure to clothianidin—but is less toxic. Basically, whatever affect imidacloprid has on bees, clothianidin’s affect is probably worse.
  2. A Common Pesticide Decreases Foraging Success and Survival in Honey Bees.” This French study revealed that when honeybees were exposed to the neonic pesticide thiamethoxam, they had trouble navigating their environment and could not find their way back to the hive. Obviously, this is a problem for the foraging honeybee. The study says this could cause a hive’s population to decrease by two-thirds.
  3. Use of Common Pesticide Linked to Bee Colony Collapse.” In what may be the most convincing evidence that neonics are to blame for CCD, Harvard researchers found that 15 out of 16 hives exposed to imidacloprid during a study died. The hives treated with the highest level of the chemical perished first.

On March 21, 2012, right before these most recent studies were released, 27 beekeepers and four environmental groups who were frustrated with the lack of action on CCD filed a petitionwith the EPA asking the agency to take clothianidin off the market until a complete, scientifically-sound review of the pesticide is conducted.

These studies could finally help bring about a ban to these dangerous pesticides— and well-informed consumers can help push for this action by staying informed. For more information on Colony Collapse Disorder, check out Vanishing of the Bees (read Ecocentric’s review here) and Colony, fantastic films that make this important information accessible to people of all levels of engagement.  Vanishing of the Bees also offers a study guide for teachers and has partnered with organizations such as Beyond Pesticides to help bring awareness to pesticides role in this growing ecological threat. There is now hope that the combined efforts of activists, scientists and the growing number of concerned consumers will start to pay off—and that the EPA will finally take action to help save the bees and restore our ecosystem’s precious balance.

Don’t be surprised if you see some pro-chemical bee research – and maybe some chemical “solutions” to the CCD problem -- released in the near future. Last fall, Monsanto quietly acquired Beelogics, “an international firm dedicated to restoring bee health and protecting the future of insect pollination. Through continuous research, scientific innovation, and a focus on applicable solutions, Beeologics is developing a line of products to specifically address the long-term well being of the bees.” Hat tip to Natural News.