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Dr. Laurence Packer

Dr. Laurence Packer in the field

Dr. Laurence Packer has been a lifelong entomologist. Bees are his specialty, but his interest in six-legged creatures began at a very early age.

“When I was too young to remember anything my parents – my dad in particular – tried to make sure I wasn’t scared of insects,” he told Planet Experts. “And I guess I overreacted.”

Jovial and forthcoming, Dr. Packer is all too eager to regale his listeners with tales of nature’s most popular pollinator. His research has taken him across the world and to almost every continent in search of new species of Apoidea (the superfamily that includes wasps and bees), and he has documented his travels in the book, Keeping the Bees, which was recently reprinted in a new paperback edition.

Keeping the Bees

Keeping the Bees

In the book, Packer talks relatively little about honeybees, whose preeminent place in the media has obscured the 20,000 or so other species of bee. While Colony Collapse Disorder has decimated populations of honeybees across the U.S. and remains a significant concern among beekeepers and agriculturists, it is a phenomenon that affects a small percentage of worldwide bee species. Packer’s book focuses on wild bees, less well known but in no lesser danger of disappearing.

A melittologist (one who studies wild bees), Dr. Laurence Packer obtained his B.A. in Zoology from the University of Oxford. He went on to earn his Ph.D. from the University of Toronto and is currently a Professor of Biology at York University, where he has served since 1988. Last weekend, he took some time out of his busy schedule to discuss his work with Planet Experts.

The Disappearing Bees

Packer began collecting butterflies and moths at the age of four or five, a hobby that expanded when he entered university. As he explains, his focus eventually centered on bees and wasps, “for aesthetic reasons more than anything else.”

“That is the main reason I got into them,” he reiterates, “they’re just beautiful to look at.”

But in the last few decades there are fewer bees to look at. Packer and his colleagues have analyzed the data and the fact is unavoidable. “There are definite declines both in terms of number of species and in terms of the abundance of some species,” he explains.

Caupolicanini Female

Caupolicana fulvicollis

Several bumblebees are now on various countries’ endangered species lists. “Here in Canada we have the Rusty Patched Bumblebee that used to be the third most common species in southern Ontario – most people in Toronto would find it in their gardens. And now there’s only one place in Canada where it’s found, and even there we only find it once every few years. So it’s there in such small numbers it may well have completely disappeared by now. I think the last time we saw it was maybe 2009.”

In the U.S. in northern California and southern Oregon, Franklin’s Bumblebee has suffered the same fate. “That’s a bumblebee that may well be extinct,” Packer says.

The same is true for species across North America and Europe. Why, exactly, is not clear (the studies are ongoing), but Packer enumerates several contributing factors.

“It could be a mixture of chemicals and diseases,” he says. “Certainly disease spread has been implicated in the catastrophic reduction of what is one of the biggest bees on the planet, which is found in Patagonia, Southern Chile and Southern Argentina.

“When they introduced bumblebees from Europe for greenhouse pollination, the diseases that came with them got out – the bees escaped – and are taking over the southern parts of those countries. The native bee that suffered as a result (Bombus dahlbomii) was a spectacularly beautiful thing. It was bright orange – it looked like a flying hamster.

“The populations of that have crashed and I suspect it’s partly to do with competition but also, I would guess, diseases. …But when we look at all of the bees put together, work done in Britain, the Netherlands and in North America has showed that the diversity of bees has gone down over time.”

Lithurgini Male

Trichothurgus dubius

To illustrate, Packer points to an important study by the nineteenth century entomologist Charles Robertson. In the late 1800s and early 1900s, Robertson rode around Carlinville, Illinois in a horse and buggy, documenting all the bee species he could find. The study was replicated around 1970 and turned up most of the same species. Then something changed.

“The study was replicated again in 2009-2010 and they found that half the species had disappeared over the intervening few decades. So things were staying pretty much the same for seventy-five years and then dropped quite noticeably.”

What Fewer Pollinators Means for Global Consumers

Most wild pollinators are bees, and a drop in global bee populations will have a correlative effect on global crops. But Packer is quick to point out that the impact won’t be as catastrophic as it is sometimes claimed to be.

“I think it’s easy to exaggerate this,” he says. “You’ll often find people say things like, ‘Every third mouthful of food is brought to us by a pollinator.’ That’s a huge exaggeration. Maybe it’s 10 percent, and that’s likely to be a bit of an exaggeration.”

Xeromelissa rozeni

Xeromelissa rozeni

The professor goes on to say that it is “highly unlikely” that all bees will one day disappear. What is more likely to happen is that overall bee species will be diminished. “So rather than having a dozen bumblebees in an area you get four or five that you can’t find anymore and a couple of the others become super abundant.”

Ultimately, this simplification will be what harms crops. The more succulent and nutritionally valuable foods – most fruits, vegetables and nuts – require pollination, and the best kind of pollination is achieved when multiple species are involved.

“Having a diversity of pollinators actually increases the yields. There have been studies done on watermelon and other crops that show that even if you keep the number of flower visits the same, if you get ten visits per flower, it’s better to have each of those visits done by a different species of bee than having them all done by the same one.

“Presumably this is because each bee visits the flower in a somewhat different way, each species will deposit pollen somewhere slightly different on the stigma. For example, with watermelons, to get a good nice oval watermelon you need 1,750 pollen grains. It may take half a dozen visits to do that. If they’re all done by one species of bee, maybe those pollen grains will stack on top of each other and some of them can’t develop into the stigma and end up fertilizing what becomes a seed.

“So if all bees disappeared – that’s highly unlikely – but most of the things that we like a lot, like blueberries, almonds, those would largely be unavailable. …Most of the other crops that require no pollination are the staples that are really rather boring, like the grains. We’d still have oatmeal, but we wouldn’t have watermelons.”

What Can Individuals Do to Support Wild Bee Species?

One of the major dangers facing bees is the use of pesticides on crops. There is a well-documented link between neonicotinoids (an insecticide derived from nicotine) and nervous system damage in honeybees. Less well-documented is their effect on wild bees, though Packer notes that when Europe implemented a temporary two year ban on general pesticide use, honeybee populations made a fairly quick recovery.

Euglossa

Euglossa female

In Ontario, he says, the “government is currently considering making people that want to use more than a small amount of these chemicals ask for permission to do so rather than just being able to use them whenever they want.”

The problem with pesticides is that they get everywhere. “They’re making their way into water supplies, they’re getting into birds. There are suggestions out there that the coating of a single seed might be enough to kill a single bird, so there’s a lot of controversy going on about a lot of this.”

What the melittologist can claim, however, is a green thumb. On an individual level, there are several things gardeners can do to support the natural development of wild bees. (And these tips are much simpler than buying “bee-friendly” seeds, which carry with them their own assortment of problems.)

Encouraging a diversity of bees is integral to a healthy ecosystem, and relatively easy. On the other hand, says Packer, it involves a few practices that are counter-intuitive to a tidy garden.

For instance, “a tidy lawn is pretty much a wasteground. There are a few bees that will nest in a nice lawn and people don’t like that because they make little brown patches of soil if they dig down.”

Ctenocolletes-smaragdinus

Ctenocolletes smaragdinus

The best kind of lawn is one with patches of bare dirt, because most bees nest in the ground. Avoiding mulch is also key. “You don’t like having compost poured over your house and bees don’t like it either.”

Also, feel free to keep old twigs and stems in the yard. “Leave [them] where they are because there’s lot of bees that nest in old stems, especially things like raspberry canes. I’ve got three different genera of bees nesting in the raspberry canes in my garden.” The same goes for old wood. In Packer’s garden, “we’ve got a grape arbor that’s used by two genera of bees to nest in and the wood’s getting a little soft in places.”

It may seem like an architectural nightmare, but holes in the walls are also perfect for certain bee species, as well as wasps. When I point out that few people would put off regrouting their brick just so they can house wasps, Packer laughs and clarifies: “These are solitary wasps, not the yellow jackets that sting so bad. And most of these solitary wasps are actually going to be collecting caterpillars and aphids and things like that from the garden, so they’re actually doing biological control for you.”

Avoid using chemicals in your garden and avoid the standard-issue horticultural varieties. “The plants that are best for bees are going to be the ones that are comparatively easy for them to get pollen in. Wild roses are really good because it’s like a saucer of food for the bee because the anthers are sticking out in the middle and the bees can just land on the plant and get the pollen straight away.

Mydrosoma-micheneri

Mydrosoma micheneri

“You get a horticultural variety rose and all the petals are crowded together and the bee has to force its way through.” Packer dismisses these flowers from the bees’ perspective. “I don’t think many of them bother. They might land on the flower, wander around for a bit confused, and then leave.

“The simpler the structure of the flowers the better. Wild flower gardening is particularly good because the bees in the local area will have interacted with those for pretty much ever whereas horticultural varieties, these are new and often difficult for the bees to access.”

Dr. Packer’s book, Keeping the Bees, is now available in e-book and paperback formats.

(All images courtesy of Dr. Laurence Packer’s Bee Research Laboratory at York University.)

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