With all the talk about honey bee nutrition lately, just how much food does a honey bee colony need and how far can the workers fly to find find it?
"A healthy honey bee colony requires approximately 50 pounds of pollens and 100 pounds of honey to survive for 12 months," says Extension apiculturist Eric Mussen of the UC Davis Department of Entomology and Nematology, who will speak at both the Western Apicultural Society Conference and the California State Beekeepers' Conference this fall.
"Honey production exceeding 100 pounds may be harvested as a honey crop," he says. "From spring until late fall the adult honey bee population turns over at a rate varying from an initial high of around 2000 bees a day to 1000 in the summer, and to 0 in areas with real winter."
During the peak season, a queen bee can lay 2000 eggs a day. That's a lot of mouths for the nurse bees to feed. They need food, and lots of it.
"In order to meet the nectar and pollen demands to feed all that brood (immature bees) each colony has to have an acre-equivalent of honey bee-attractive bloom within foraging flight range," Mussen says. That's up to four miles from the hive and covers a 50-square mile area.
The foraging field force of a honey bee colony, he says, usually consists of one-third of the total population. Some 40,000 to 50,000 bees comprise a colony during the peak season. The foraging population is subdivided into groups of bees specializing in collecting water, nectar or honeydew, pollen, or propolis (plant resin).
That's a lot of work for the foragers.
Here's how the numbers roll.
Statistics show that California has a total land mass of 104,765,440 acres. Of that, fresh water covers 4,949,760 acres. "The remaining 99,815,680 acres are solid ground," Mussen says.
"Our best estimate is that California beekeepers maintain 500,000 colonies of resident honey bees, the number of colonies in California swells to around 1.6 million during almond pollination."
There's plenty of food for the bees during almond pollination season, as California almond acreage totals more than 800,000. Later, though, beekeepers are looking for temporary places to put their bees.
If bees were placed on prime locations, "they would require flight access to between 1 to 1.6 million acres, or approaching a maximum of 1.6 percent of California's landmass," Mussen points out.
"The demand for honey bee forage exceeds the floral quantities in areas readily available to beekeepers. To negate the need for having to feed the colonies supplemental, artificial feed, beekeepers hope to gain access to more areas that appear to contain adequate food. Besides being expensive, artificial feed does not contain all the required nutrient or the necessary microbial complex to meet the needs of honey bees."
That's why there's a concerted drive, Mussen says, for growers to provide "more bee forage along their field edges, interplanted as cover crops, or on fallow ground that they control."
Residents can do their part, too, by providing bee friendly plants.
And that's not just food for thought. It's food for the bees.
University of Minnesota honey bee researcher Marla Spivak, in her TED talk on honey bee health, referred to bees as "flower feeders."
That they are. Flower feeders.
As are other pollinators from butterflies to beetles to bats.
But it's a special treat to see butterflies, honey bees and carpenter bees sharing blossoms of the same plant, the passionflower vine (Passiflora).
Several years ago a UC Davis professor planted a fenceline of passionflower vines at her residence off east Covell Boulevard, Davis. This year she is reaping her reward: Gulf Fritillaries (Agraulis vanillae), honey bees and Valley carpenter bees are all over it. Why Gulf Frits? The passionflower vine is their host plant. You can see the entire life cycle from egg to caterpillar to chrysalis to adult in her yard.
The Valley carpenter bees (Xylocopa varipuncta) are frequent foragers, too. The females frighten many people because of their size and loud buzz. They're a solid black, in sharp contrast to the males, which are golden with green eyes.
We didn't see one predator Thursday in her Davis yard.
In our yard, we have scores of predators on our passionflower vines: scrub jays, European paper wasps, jumping spiders, ladybugs, assassin bugs and an occasional praying mantis. Although the jays pick off the caterpillars from our passionflower vines, they don't seem to go for the adults.
Butterfly expert Art Shapiro, distinguished professor of evolution and ecology at UC Davis, points to research published in a 2007 edition of the Journal of Chemical Ecology that indicates that the Gulf Fritillary adults are poisonous to birds. A team of scientists from Maryland, Virginia and Georgia wrote in the abstract of their article, “Novel Chemistry of Abdominal Defensive Glands of Nymphalid Butterfly (Agraulis vanillae): “Abdominal defensive glands of both sexes of the Gulf Fritillary butterfly, emit a pronounced odor when disturbed…we suggest that the constituents in the glands may play a defensive role against potential avian predators.”
The article relates that Linnaeus (1758) first described the tropical butterfly and noted that its brilliant coloration of the reddish-orange butterfly makes it conspicuous.
It's critical issue.
Mussen, an Extension apiculturist based at the UC Davis Department of Entomology and Nematology since 1976, says malnutrition is a major factor in the declining bee population. That, along with pesticides, pests, diseases and stress.
"You, no doubt, have lost track of how many times I have stated that malnutrition is a leading factor in our unacceptable annual bee colony loss numbers," Mussen writes in the latest edition of his bimonthly newsletter, from the UC Apiaries, available free on his website.
"I have also stated innummerable times that our synthesized bee diets just cannot match the value of nutrients obtained by bees from a mixture of quality pollens. My concern has been that although we have a very good idea of the protein requirements for honey bees, the rations of essential amino acids honey bees require, and their required vitamins and minerals, etc., we still cannot feed bees on our best diets and keep them alive more than two months in confinement."
"Thus, we are missing some very critical components in our synthesized diets. If we could find those components, could we formulate a diet that would sustain bees in a healthy condition during 'feedlot beekeeping'?"
Mussen touches on a recent study that shows a component in honey, p-coumarin, stimulates "the honey bee immune system to work better."
However, it's not the honey that's doing this.
"Actually," Mussen says, "that chemical is a contaminant of honey that comes from pollen grains that are mixed into the honey during the bees' processing cycle. Thus, the bees need only to consume the pollen to obtain the desired results. How many other minor chemicals are there in pollens that are so useful to honey bee health?"
You'll want to read what he says about floral pollens containing microbes. "If these microbes are really so important to the nutritional needs of honey bees, what are we doing when we introduce antibiotics and fungicides into the system?"
Bottom line: we need more research to see what's going on with pesticide exposures and reduced microbial levels.
Or as Mussen says: "As researchers continue to try to improve upon our supplemental bee feeds, they have to consider the possibility of inoculating a semisold formulation of the diet with fresh pollen and stored pollen so that a natural microbial complex can do its things and make the food appropriately fit for consumption by honey bees."
To bee or not to bee--a photographer.
Capturing images of honey bees is a delightful leisure activity.
You don't have to sign up for a safari on another continent, or invest in thousands of dollars worth of camera gear.
You can do it all in your backyard (especially if you provide bee friendly plants). Or, you can head for a bee garden or park.
Lately, my objects of interest are the honey bees foraging on our tower of jewels (Echium wildpretii). Earlier this spring, five towers of jewels graced our backyard. Now we're down to one; the others are spent. (They're biennuals and have completed their life cycle.) The sole Echium apparently doesn't know it's time to quit; it has been blooming off and on since April.
Which is wonderful for the bees, beekeepers and photographers!
To get photos of honey bees, I don't poke 'em, prod 'em or pin 'em. I don't spray 'em, glue 'em or freeze 'em. The bees do what they do naturally; I am a visitor in their habitat. I quietly pull up a chair--keeping low to the ground and as obscure as possible--and watch them. No, they won't sting you when they're foraging. They are more likely to show defensive behavior when you're too close to their hive entrance (such as blocking their flight path); when you haven't smoked the hive properly; or when you swat at them.
Lighting is everything. Photography, in Greek, means "writing with light" and that's what you do. Write with light. A little backlighting and a honey bee absolutely glows. Adjust your camera settings and you can stop a bee in flight or capture the redness of its tongue (proboscis).
Early in the morning is the best time to photograph bees. Their flight muscles haven't quite warmed up yet; they move at a slower pace; and they linger longer on the blossoms. One of the bees below clung to the same Echium blossom for two hours before it buzzed off.
These photos were all taken around 7 a.m. the same day on the same plant. The tools: a Nikon D800 camera and a 200 mm macro lens.
Cameras are just that--a tool. They don't make the image; the photographer does. Folks who say "You must have a nice camera" don't understand the creative process or the making of an image. They would never tell a gourmet cook "You must have a nice set of pots and pans" or an artist "you must have some nice brushes" or an athlete "You must have a nice pair of shoes."
That being said, bee photography is something each of us can do, each in our own way.
Read your camera manual. Know the settings. Know what your camera can and cannot do. Learn from other photographers. Look at photos in art galleries, in publications, or on the web. Then head out for a bee safari.
On an African safari, you may not find "big game." But on an insect safari, you will always find "little game."
As summer nears its end, the honey bees are hungry.
That's why Extension apiculturist Eric Mussen of the UC Davis Department of Entomology and Nematology advocates that we plant flowers for late summer and fall to help the bees. Often we think of spring as the season for planting bee plants, but mid- to late summer and fall is when they really need our help.
Malnutrition is one of the factors suspected in colony collapse disorder (CCD), the mysterious malardy in which adult bees abandon the hive, leaving behind the queen bee, immature brood and food stores. Other factors in the declining bee population include pesticides, pests, diseases and stress.
If you look around, you'll see bees foraging in Northern California on blanket flower (Gaillardia), sedum (family Crassulaceae) and late-blooming towers of jewels (Echium wildpretii).
And the lavenders, salvias (sages) and the mints.
Current resources? The Xerces Society for Invertebrate Conservation features plant lists on its site. The UC Berkeley Urban Bee Lab maintains a wealth of information about plants and pollinators on its site. There's even a Bee Smart app, offered free by the Pollinator Partnership, that will enable you to browse through about 1000 native plants.
Some of my favorite honey bee plants: the lavenders, the salvias, sunflowers, catmint, sedum, blanket flowers, oregano, artichoke, zinnias, cosmos, borage, bush germander, buckwheat, basil, ceanothus, coneflowers, seaside daisies, red hot poker, and of course, the tower of jewels, which, in height, towers over them all.