Colony Collapse Disorder
Colony Collapse Disorder is the phenomenon that occurs when the majority of worker bees in a colony disappear and leave behind a queen, plenty of food, and a few nurse bees to care for the remaining immature bees and the queen. (EPA) Starting in the last three months of 2006, what seemed a new phenomenon began to occur based on reports of an “alarming” number of bee colony losses and die-offs along the East Coast. By the end of 2006, beekeepers on the West Coast also began to report “unprecedented” losses. Estimates indicated that beekeepers in 35 states were affected.31
Discovering a Problem
During the winter of 2006-2007, some beekeepers began to report unusually high losses of 30-90 percent of their hives. As many as 50 percent of all affected colonies demonstrated symptoms inconsistent with any known causes of honeybee death: (1) sudden loss of a colony’s worker bee population with very few dead bees found near the colony, (2) the queen and brood (young) remained, and the colonies had relatively abundant honey and pollen reserves.
But hives cannot sustain themselves without worker bees and would eventually die. This combination of events resulting in the loss of a bee colony has been called Colony Collapse Disorder.32
What followed was global concern over a new phenomenon. Scientists realized that it was not just the US that was losing its honeybees, but that similar problems had manifested all over the world. To make things worse, areas were also losing many populations of wild bees too. Losing bees can have tragic consequences. Bees are pollinators for about one-third of the plants we eat, a service that has been valued at as much as $168 billion worldwide.
Dead Bees Don’t Necessarily Mean CCD
Honeybee colony losses are not uncommon. A recent report by the National Research Council (NRC) documents extensive literature on honeybee population losses due to bee pests, parasites, pathogens, and disease. Most notable are declines due to two parasitic mites, the so-called vampire mite (Varroa destructor) and the tracheal mite (Acarapis woodi), and also colony declines due to the bacterial pathogen Paenibacillus larvae. Other reasons for bee colony declines reported by the NRC include competition between native and introduced bees, pathogen spillover effects, habitat loss, invasive plant species that reduce nectar- and pollen-producing vegetation, bee genetics, and pesticides, among other factors.33
Certain pesticides are harmful to bees. That’s why we require instructions for protecting bees on the labels of pesticides that are known to be particularly harmful to bees. This is one of many reasons why everyone must read and follow pesticide label instructions. When most or all of the bees in a hive are killed by overexposure to a pesticide, this is considered a bee-kill incident resulting from acute pesticide poisoning. But acute pesticide poisoning of a hive is very different from CCD and is almost always avoidable.
Several incidents of acute poisoning of honeybees have been covered in the popular media in recent years, but sometimes these incidents are mistakenly associated with CCD. A common element of acute pesticide poisoning of bees is, literally, a pile of dead bees outside the hive entrance. With CCD, there are very few if any dead bees near the hive. Piles of dead bees indicate that the incident is not colony collapse disorder. Heavily diseased colonies can also exhibit large numbers of dead bees near the hive.
Though agricultural records from more than a century ago note occasional bee “disappearances” and “dwindling” colonies in some years, it is uncertain whether the colonies had the same combination of factors associated with CCD. What we do know from the data from beekeepers for 2014/2015 is that, while colony loss from CCD has declined, colony loss is still a concern.34
Do We Understand Why?
The good news is that there has been plenty of progress in the past decade in understanding the mystery of Colony Collapse Disorder. The bad news is that we now recognize it as a complex problem with many causes, although that doesn’t mean it is unsolvable.
For all bees, foraging on flowers is a hard life. It is energetically and cognitively demanding; bees have to travel large distances to collect pollen and nectar from sometimes hard-to-find flowers and return it all to the nest. To do this they need finely tuned senses, spatial awareness, learning, and memory.
Anything that damages such skills can make bees struggle to find food, or even get lost while trying to forage. A bee that cannot find food and make it home again is as good as dead. Because of this, bee populations are very vulnerable to what are called “sublethal stressors” – factors that don’t kill the bees directly but can hamper their behavior.35
If all bees died it may not be a total extinction event for humans, but it would be a disaster for our planet. We would see a domino-like effect as many plants started to just disappear one by one, and all animal species would start to struggle to find food.
Herbivores, who depend on certain plant species, would be affected first. They would simply become extinct if those plants ceased to exist because bees were no longer pollinating them.
The animals that fed on those animals would be the next to starve and face extinction... and so on as each link in our natural food chain broke down. The price of food and medicines would become out of control, leading to an economic disaster.
Lastly, without bees, there would obviously be no honey! We would be losing one of the healthiest, most versatile, and most natural food products available. One of our favorite baking and cooking products would be gone and beekeepers would have no bees to look after. We would miss the honey in skin remedies, shampoos, and other cosmetic products. Beeswax would also no longer exist.
It's almost impossible to overstate how much bees play an essential role in the global food supply and the natural balance of the planet. It's essential not just for us that bees survive, but for every living thing on the planet.37
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