Do you like melons, including watermelon? Do you use pumpkin, zucchini, or other squashes? Maybe you like to eat more exotic produce, such as kiwi fruit or passion fruit, or nuts such as Brazil nuts and macadamias. For all of these, pollination by bees is essential. If there were no bees, the yield per acre of these crops, if they could be commercially grown at all, would be 1/10 or even only 1/100 of what it is at present.
Maybe you like apricots, blueberries, loquats, peaches, plums or cherries; or how about almonds or cashews; maybe pears, apples, or raspberries. My wife, along with many, adores cucumbers and eggplant. All of these also need bees to bear well. These crops and many others are listed as having "great" need for bees to pollinate them in resources such as this Wikipedia page. Overall, bee pollination is responsible for about one-third of our food supply.
I have not yet specifically mentioned honeybees. Honeybees can and do pollinate all these crops and many more. For some of them, only honeybees seem to do an economical job of it. But there are 20,000 species of bees so far known worldwide, and 4,000 of them are found in North America. Most of them are pollinators also.
I won't go into Colony Collapse Disorder or other ills that are presently wiping out so many colonies of honeybees. Rather, with such problems as a background, we need to be thinking about what we will do if the principal species of honeybee soon become extinct. Knowing that there are so many thousands of species of native bees, and knowing that most native bees are also pollinators, we need to ask, can they do the job if honeybees fail?
In Our Native Bees: North America's Endangered Pollinators and the Fight to Save Them, Paige Embry takes aim at this question. As the title makes clear, many of the native bees are suffering declines along with honeybees, for a variety of reasons. Some of them are prone to the same diseases and mite infestations that are part of the problems honeybees are having. Others are being wiped out just because they are "little dark things" that we don't notice when we decide to monocrop a field that was once part of a more traditional (multi cropped) farm; or to spray a new (or old!) insecticide that hasn't been tested for native bee safety; or to either drain a pond or create a new one.
One such is the tomato. Ms Embry got interested in bees when she discovered that only bumble bees can do "buzz pollination" that tomato flowers need to release their pollen. Honeybees aren't strong enough. Other flowers are too long or deep. In the picture above, the two bees at the left of the second row are shown with their mouth parts extended. They can pollinate flowers that honeybees cannot reach into. The green one is a kind of sweat bee, so-called because it will also extend that long "tongue" to lick sweat off your body on a hot day. The sweat bees I knew as a child were brownish yellow and looked more like a half-size honeybee. But the ones here on the Atlantic coast of the U.S. are shiny green or green-and-yellow. Sweat bees can sting, not nearly as painfully as a honeybee, but most bees smaller than that don't sting.
A significant few chapters of the book are about BOB's, the Blue Orchard Bees. They are one kind of mason bee that scientists are experimenting with, to see if they can be produced and cultivated to compete with honeybees in, for example, the huge almond and cherry orchards of central California. One benefit of BOB's is that they are much more efficient workers than honeybees, by a factor of about 10! Thus, if you need a hive of 30,000 honeybees to pollinate an orchard (that would be a small orchard), a box of "tube cards" containing only 3,000 BOB's could do as well.
One great problem of beekeeping, whatever sort of bees one keeps, is keeping them alive when the flowers aren't blooming. BOB's don't make honey to tide themselves over the winter the way honeybees do.
As an aside, when I lived next door to a commercial beekeeper, he told me that he and his employees would make sugar syrup, which is much cheaper than honey, to feed his bees over the winter. I wonder how healthy those bees were come spring. The syrup doesn't have all the micronutrients that honey has.
BOB's store pollen instead of honey, and their young winter over in the tubes the mother bee fills with pollen pellets (I am oversimplifying). When they emerge in the spring, they need to find sources of pollen right away. Thus in other portions of the book we read of places such as golf courses that work with initiatives such as Operation Pollinator. Instead of managing the "rough" in a golf course as just another grassy field, the groundskeepers can mix in a variety of blooming plants. Not only do bees do better, but many golfers like the "wilder" (though still managed) appearance of the rough alongside the fairways.
This can also work in our yards. Many suburban yards have flower beds and borders. Most bees are not too picky, so even if we like to plant a lot of non-native flowers, they'll draw bees of many species. But we can also make sure to have something blooming all through the spring, summer and autumn. Even the grassy areas can have some flowers: my yard, for example, has a lot of white clover, which is beloved of many bees. I have a front yard and side yard (the back yard is too shady to support clover). I mow then on different schedules so that there is always some clover in flower somewhere in my yard all summer long. But I have a variety of non-grass areas where I can add more bee favorites.
This is one of my pictures of a bee on the bloom (the central part of the flower is about 2 inches across). I understand this green-and-yellow bee is also a sweat bee (I am no expert). The most common visiting bees were bumble bees.
I am optimistic that, even if there are many fewer honeybees on the job in the future, native bees can pick up a lot of the slack. All of it? Probably not. It may be that our diets will change somewhat. Meantime, understanding bees better can only help, and this book is a big help.
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