Pollinating drones: Cool patent. Wise investment?
By: Matt Kelly
Tags: Science, Agriculture, Bees, Economics

By now you’ve heard the news: Walmart has applied for a patent for drones to pollinate crops. In fact, Walmart Stores Inc. has applied for several patents for unmanned vehicles that would be used for a variety of farming purposes. But the drone that would collect pollen from one flower and dispense it to another is what gained the most attention.

Despite all the headlines and several references to Black Mirror, the systems described in the application are pretty mundane; a long, broad list of the possible “embodiments” for a pollinator drone. And it shouldn’t be surprising that Walmart would want to hold such a patent: The retailer is now in the business of food, big time. If there’s one thing Walmart aspires to do exceedingly well, it’s minimize the risks in its supply chain. With the continued impact of colony collapse disorder among honey bees and the mounting evidence of population declines among wild bees — and a significant portion of the fruits and vegetables we eat dependent on the transfer of pollen — it seems pretty obvious why Walmart might be interested in building and maintaining a fleet of pollinator drones.

So what might it cost Walmart to do this? Because the patent application is filled with general possibilities and the company has decided not to share any further details, we can only make an educated guess for now. However, current real-world efforts in this area are focused on tiny drones acting like individual bees. So let’s presume that the retailer would build on this work instead of starting from scratch.

Last year David Goulson, professor of biology at the University of Sussex and founder of the Bumblebee Conservation Trust in the United Kingdom, wrote a blog post about robotic bees. In it, he addressed this question of expense:

“While I can see the intellectual interest in trying to create robotic bees, I would argue that it is exceedingly unlikely that we could ever produce something as cheap or as effective as bees themselves… Consider just the numbers; there are roughly 80 million honeybee hives in the world, each containing perhaps 40,000 bees through the spring and summer. That adds up to 3.2 trillion bees. They feed themselves for free, breed for free, and even give us honey as a bonus. What would the cost be of replacing them with robots?”

Goulson goes on to do the math, saying that if it cost just a single penny a piece to build these drones (“which seems absurdly optimistic”), it would cost £32 billion ($45 billion) to replace every honey bee. To say nothing of what it would cost to research, develop and ultimately maintain (or regularly replace) this fleet of drones.

Applying this same basic calculation (with a few adjustments) to our American context, the cost for Walmart might look something like this:

There were 2.62 million honey bee colonies in the United States at the beginning of 2017, according to the USDA. An average colony has around 60,000 bees in it.

Only about a third of a colony are foraging bees, the ones who facilitate pollination in their daily hunt. Say 20,000 for an average colony.

That means there are approximately 52.4 billion honey bees that might need to be replaced in the U.S.

At one cent a piece, it would cost $524 million just to manufacture this many pollinator drones.

Of course, replacing all of the foraging honey bees might not be what Walmart intends to do. After all, it’s not as if every single honey bee is going to disappear instantly at the same moment. Walmart may only need to make up for the loss of some of those bees. Let’s say the retailer plans for its drones to cover the work of just 10 percent of the total number of colonies in the United States. In that case, it would cost $52.4 million to manufacture enough drones.

These calculations do not include the R&D, maintenance and disposal costs of the drones. (Yes, disposal costs. Who’s going to clean up all these things when they break and fall to the ground?) Nor do these calculations include what it might cost to also replace the wild bees and other pollinators that do a significant amount of pollination work for farms. Even for a company that had annual net income of $9 billion in 2017, the costs associated with a fleet of pollinator drones could add up quickly. Especially if they cost more than a penny to manufacture: even a dollar-a-piece production cost (which also seems absurdly optimistic) would suddenly inflate the initial price tag into the billions of dollars.

Yes, Walmart reported over $485 billion in total revenue for 2017, and food sales account for more than half of that amount. So in that light, even a $5 billion price tag for UAVs might seem to be a reasonable investment. However, the company is planning to spend only around $11 billion for capital expenses in 2018; how quickly would a pollinator drone program (even an absurdly inexpensive one) consume the company’s capex budget?

Now consider this other point that Goulson made in his post: Real-live bees feed themselves, groom themselves, and reproduce essentially for free.

So why not take care of the pollinators we already have and give the simple sum of $52.4 million to conservation organizations instead? With that amount of money, what could be accomplished in just a single year?

“It is actually quite hard to work out what conservationists might do with such a vast sum of money,” says Goulson via email. For example, the Xerces Society for Invertebrate Conservation spent $1.9 million on its pollinator conservation programs in 2016. “Fifty-two million dollars, let alone $520 million, seem like unimaginable sums,” says Goulson. “If they did have this sort of money, there is no doubt that they could run a vast program of outreach and habitat creation that would benefit all terrestrial life, not just bees.”

“If we consider the fact that an aesthetically-beautiful, wildlife-supporting, carbon-sequestering and oxygen-producing wildflower meadow can be established in most parts of the U.S. for around 10 cents per square foot, then the best return on investments is clear,” says Eric Lee-Mäder, Pollinator Program co-director for the Xerces Society. “We should all plant wildflower-rich habitats rather than build drones that don’t do any of those things.”

At a rate of 10 cents per square foot, $52.4 million could plant about 12,000 acres — over 9,000 football fields — in pollinator habitat.

In the United Kingdom, says Goulson, farmers can get subsidies of around $600 per hectare (2.47 acres) to create high-quality habitat for bees on their land. If a program with the same incentive were offered in the U.S., $52.4 million would pay for over 215,000 acres to be planted (over 160,000 football fields).

“There is no doubt that this would be an enormous boost to pollinator populations, and to wildlife generally,” says Goulson. With a caveat. “But neither I nor anybody else could tell you whether it would be ENOUGH to permanently maintain healthy pollinator populations across the U.S.A.”

So what if Walmart gave $52.4 million every year for several years to conservation organizations?

After reaching out to the company several times, Walmart ultimately provided the following response to the specific calculations and questions in this story: “As mentioned, we’re always thinking about new concepts and ways that will help us further enhance how we service customers, but we don’t have any further details to share on these patents at this time.”

If Walmart hasn’t crunched the numbers on pollinator drones, it will be interesting to see exactly what concepts the company starts thinking about once it does. But if the retailer has already determined that a fleet of drones is good for the bottom line, the details of those plans are going to be equally fascinating to see.