May 26 2016

What’s Killing the Bees

honeybeesYesterday I saw a bumper sticker that stated, “Save the Bees, Buy Organic.” Of course, a bumper sticker is not the place for a nuanced or thorough treatment of a complex topic. It is a venue suitable for simplistic slogans.

People like simple narratives, but reality rarely conforms to our desires. This has led to a frequent reminder, popularized by Ben Goldacre, that you will often find the situation (pretty much whatever situation you consider) is more complex than it might at first seem. That is a good rule of thumb – it is fair to assume as a default that any topic is more complex than your current understanding, or how it is being presented in the media, or how it is understood in the public consciousness.

Complex and ambiguous situations, like the fate of our pollinators, become a convenient Rorschach test for ideology. People tend to impose on this complex and not fully understood situation whatever simplistic narrative suits their beliefs and values, like the notion that organic farming will somehow save the bees.

What’s Up with the Bees

You cannot talk about honey bees, bumble bees, and wild pollinators without mentioning that about one third of the food we produce is dependent on such pollination. The implications are clear – if bee populations collapse, human populations may suffer a similar fate.

Starting in 2006 commercial bee owners noticed a dramatic increase in their winter losses. In addition, they noticed that some hives appeared to be completely abandoned by adult workers, leaving the hive vulnerable and leading to its collapse. This phenomenon was called colony collapse disorder (CCD).

Many people blamed their favorite boogeyman for CCD. They assumed their preferred narrative and then confirmation bias kicked in to prove that they were right. Meanwhile, scientists trying to figure out the actual cause of CCD discovered a complex mix of factors, and no one simple explanation.

Also, the problem of CCD has largely resolved, although population declines continue to be higher than normal. Bee keepers have been able to compensate by breeding new colonies to replace losses, but this is increasing the cost of pollination to farmers.

Elina L. Niño (I love the inclusion of her middle initial), an extension apiculturist for the University of California Cooperative Extension, recently wrote an excellent article summarizing our current understanding of CCD and bee population losses in general. It’s a quick read that will put the situation into perspective.

The bottom line is that the stressors on pollinators are many, including a combination of biological and environmental factors. Pesticides are likely playing a role, but bee parasites are also an undeniable huge factor.

One parasite in particular, the mite Varroa destructor, is a particular problem. Bees, however, are also under pressure from viruses and fungi.

The core problem, which mirrors the challenges faced for crops as well, is that bee keepers are keeping massive populations of bees (like growing millions of acres of crops). Whenever there are millions of something, that creates a massive evolutionary pressure for pests to evolve to eat that something.

It seems we are engaged in yet another arms race with evolution. We are trying to develop pesticides to kill off parasitic mites and other bee pests, without harming the bees, and to do so faster than the parasites are evolving resistance. Niño, like many other experts, recommend integrated pest management (IPM) as a way of keeping pests at bay while minimizing resistance and the effects on the environment.

What about the effect of crop pesticides on friendly insects such as honey bees and wild pollinators? Neonicotinoids have come under fire for their toxicity to honey bees. Yet again, the situation is complex.

A recent review found that neonicotinoids are indeed toxic to honey bees in concentrations that they can get exposed to with agricultural use. However, the same review found no evidence that neonicotinoids are actually causing a decrease in honey bee populations. The power of the evidence, however, only limits such population declines to <20%. Others point out also that the effects on wild pollinators are not as well known, and may be greater.

Given this evidence, it seems likely that neonicotinoids contribute to the overall environmental stress to pollinators, but are not the dominant cause of population declines.

Is Organic Farming the Answer?

In a word, no. What we need is IPM – using the best methods available according to the best evidence. There may be some sustainable methods preferred by organic farmers that are useful, and other practices that are harmful. Similarly there are some practices preferred by conventional farmers that are better for pest management, while other practices are counterproductive.

As I have argued before, we need to get beyond the false dichotomy of organic vs conventional farming – I know this won’t happen, because “organic” is a lucrative marketing brand.

One big problem with organic farming is that they often do use pesticides (despite popular belief) but they use mostly “natural” pesticides. Allowed “natural” pesticides can be as or even more toxic than the best synthetic pesticides, often require more frequent applications, and can therefore have a greater negative impact on the environment.

Organic farming also requires more land, which displaces more natural habitat to grow the same amount of food. This may have the greatest negative impact on the environment.

Further, organic farming does not allow for use of GMOs, which have been a clear benefit for pest management. The dilemma for farmers is called the pest treadmill. Use of pesticides to control harmful insects results in resistance to those pesticides. This results in use of more and possibly more toxic pesticides. These kill off friendly insects too, including those that are predators to the crop pests, worsening the pest problem and requiring even more pesticide.

GM crops that incorporate Bt, a natural pesticide approved for organic farming, have reversed the treadmill. They allow for less pesticide use, less toxicity to friendly insects, the return of pest predators, and the need for even less pesticide. As one expert put it, they run the treadmill in reverse.

Pro-organic, anti-GMO activists refuse to acknowledge this clear win for GM technology. They would rather use toxic “natural” pesticides and harm the environment, including the bees, than use the best methods currently available. Quite the opposite of the bumper sticker, if you love the bees, you will not buy organic.

Conclusion

Growing enough food, including pollinating the one third of agriculture that requires pollinators, is a great challenge. It is similar to bacterial infections and antibiotic use. Both run up against the unavoidable challenges of evolution – pests will evolve to eat our crops, they will evolve resistance to our methods of killing them, and bacteria will evolve resistance to our antibiotics.

It does seem as if we are at a critical point with both antibiotics and pest control. We are seeing the emergence of significant resistance.

We will never (at least not with foreseeable technology) be rid of the challenge of evolving bugs. The best we can do is take a complex and evidence-based approach to minimize resistance and keep one step ahead of the bugs. With farming and bee-keeping this means integrated pest management. It also means making maximal use of genetically modified organisms.

This is not the time for simplistic ideology, which is what the organic movement is. Organic farming is based on the appeal to nature fallacy, not on science or reason. It is a wasteful luxury, primarily indulged in by privileged Westerners, that we cannot afford.

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