Honey Bee Suite » honey bee nutrition

Love that dirty water

Rusty — Tue, 01 May 2012 17:08:28 +0000

The song “Dirty Water” was released by the Standells in 1966, but it could have been written by your local bee colony. It seems honey bees prefer water that most of us would consider unpalatable.

I live in a place where water is not in short supply. There is a creek nearby—more like a small river—and two streams, one of which originates from a spring not ten feet from the apiary. Lower down are wetlands—swampy areas that never dry out and are choked with skunk cabbage and water parsley. And did I mention it rains nine months out of twelve?

But the water the bees adore seeps from the side of a hill, runs across a path to the hives, and eventually drains into one of those swampy areas. It is more mucky than wet and is home to creatures that never travel in a straight line—squigglies that slither and writhe. The area is slippery with furry green stones that emit a moldy bread aroma, but the bees belly up as if it were the best bar in town.

Given a choice, bees pick the most fragrant, nutrient-rich water they can find. Puddles, ponds, brooks, irrigation systems, bird baths, hose bibbs, and pet dishes all attract bees—so do saltwater pools and even pools with chlorine. Plant secretions and guttation drops are also known to attract bees, as well as wet compost and recently turned soil. Last year I watched bees sipping from freshly poured concrete.

The why of it is complex, but many experts think that it is the scent of the source that helps them find water, whether it be the odor of mud, mold, bacteria, or even chlorine. When you read about bee vision, you realize that they can’t see water the way we do. They fly rapidly over the ground and things appear in a blur. They see certain colors, they see movement, but they probably don’t see water. But their sense of smell can guide them to it—or, more accurately, to the things that are in it.

While we prefer water without floaters or flavors, fortified water is likely a component of honey bee health. Such water adds nutrients and vitamins to the bee diet—something that may be especially important in times of dearth or in areas of monoculture. Salt water pools seem particularly attractive to bees—no surprise since most creatures need salt for good health.

In addition, bees prefer water with edges—water with safe places to stand where they won’t drown or get swept away. On cool days in the spring and fall, warm water has an advantage over cold water since a bee can quickly become chilled from a small drink. If you want to provide a water source for your bees, keep it shallow, provide stepping stones or rafts, and wait for the slime to appear. And don’t forget to put up a sign, “Ladies Drink for Free.”

Note: I have been told that 2 tablespoons of vinegar in 1 gallon of water will keep honey bees out of pet bowls and bird baths without discouraging pets or birds. I have not tried this so I don’t know if it works.

Rusty
HoneyBeeSuite

Soon after this photo was taken, the bees began drinking from the wet concrete.

Pollen variety and bee health

Rusty — Wed, 04 May 2011 18:06:37 +0000

Bumble bee on clover

Yesterday I wrote that bees need a continuous supply of flowering plants such that something is always in bloom. I also mentioned that different types of bees prefer different types of flowers. What I didn’t discuss was the importance of pollen variety in the bee diet.

I think it is easier to understand bee nutrition when you compare it to our own. So, just now, I went to the pantry and reached for a can. It happens to be Trader Joe’s 100% pineapple juice in an 8.45 fluid ounce (250 ml) single-serve container. Good enough.

The nutrition facts printed on the side of the can tell me that one serving (the entire can) provides 2% of the daily vitamin A needs of a person who eats a 2,000 calorie-per-day diet. (Those are actually kilocalories, but that is a separate subject and a different blog.)

So, assuming I’m such a person, to get enough vitamin A by drinking just pineapple juice, I would have to drink 50 cans (422.5 ounces) or 3.3 gallons of the stuff. I like pineapple juice, but there’s a limit.

The 3.3 gallons also provides 7250 calories which is 3.63 times more than I need (assuming 2000 per day.) But it doesn’t supply any fat—which is necessary for good health—and doesn’t supply many of the other vitamins, minerals, and trace elements which keep us going from day to day. I certainly would not be very healthy living on pineapple juice alone.

You can think of a pollen grain as a “can” of food. It contains many of the amino acids, lipids, vitamins, minerals, and trace elements a bee needs, but different types of pollen contain different types of “ingredients.” The label on a can of beans will look very different from the label on the juice, just as the “label” on a grain of maple pollen looks different from the one on a grain of aster pollen.

Research has shown that when bees are forced to consume pollen that is low in nutrients they respond by eating more of it. But just as in the example above, they reach a limit. They’re full. They’re stuffed. They simply cannot eat enough of the inferior pollen to satisfy all their nutritive requirements.

Bees lacking in nutritious food are more prone to disease, don’t live as long, and can’t maintain a strong hive. Brood production falls off and eventually a colony will die. So when planning the placement of your hives, remember that the admonition to “eat a variety of foods” applies to them as well as us.

Rusty

What vitamins should I give to my bees?

Rusty — Sun, 13 Mar 2011 01:45:06 +0000

I am in no way an expert on honey bee nutrition. But in the past few years—especially since the advent of colony collapse disorder—many knowledgeable people have been studying bee nutrition under the theory that healthier bees are better able to withstand the onslaught of diseases and environmental stresses that face them. In my opinion this is an excellent line of inquiry. Living things in general do better when they are well fed.

Like most animals, honey bees need a variety of carbohydrates, proteins, lipids, vitamins, and minerals for optimum health. In nature, bees get the majority of their carbohydrates from nectar (honey) and the other components come mostly from pollen. Pollens vary in their nutritional composition, but since honey bees normally consume many different types of pollen, they are able to meet their nutritional requirements.

Trouble can occur in the hive at the end of winter when food stored the past summer is largely depleted. For this reason, beekeepers often feed pollen substitutes in the early spring. Since a full complement of amino acids (the substances that make up protein) is required to produce brood, feeding pollen substitutes in spring can help colonies get off to a good start.

Many companies now produce pollen substitutes that can be made into patties, mixed with syrup, or fed dry. Each product has been designed with a slightly different profile of the essential nutrients, but I am in no position to say which is best. I would probably trust any of the commercial preparations.

In the past, I have always fed pollen patties in the early spring and, in general, they have been poorly received. Usually they were only partly eaten before they dried into hockey pucks and I tossed them out. This year, in place of pollen patties, I decided to experiment with making hard candy enriched with pollen substitute.

The first time I put the pollen-enriched cakes in the hives I also put in some leftover plain candy cakes—I just wanted to use them up. So in each hive I put one plain candy cake and one candy cake fortified with pollen substitute. A week later when I checked the hives, I was amazed to find the pollen-fortified cakes gone and the plain ones still there. Obviously, there was something in there the bees wanted.

I have repeated this three times in the last month. My bees just love the stuff and I’m very curious to see how they do as spring approaches.

Hard candy, of course, is not something to use with a new package of bees. Although I’m not starting any new colonies this year, if I were, I would try one of the liquid amino boosters in sugar syrup along with Honey-B-Healthy. In the past I’ve used only Honey-B-Healthy and syrup, but after watching my bees munch down the pollen substitute, I’m pretty much sold on the idea.

I’m very interested to see how these overwintered colonies compare to those I’ve overwintered in the past. I will also be on the lookout for the results of controlled experiments where these “designer diets” were used. It is all fascinating.

Rusty

Monday morning myth: alder pollen is bad for bees

Rusty — Mon, 14 Feb 2011 20:01:15 +0000

I don’t know if this rumor is everywhere, but you certainly hear it here in the Pacific Northwest and in southwestern Canada. We have a lot of red alder (Alnus rubra) in this area, so that’s probably how it got started. I was reminded of the rumor when I saw my bees packing in alder pollen during yesterday’s hour of sunshine.

There is absolutely nothing wrong with alder pollen. In fact, it is one of the first pollens to be available in many areas. In this part of the country, fat alder catkins start spilling pale yellow pollen while snow is still on the ground. Being available so early, alder can be an important part of early spring build-up.

Alder trees are monoecious, meaning that both male and female flowers (catkins) appear on the same tree. Male catkins of alder are long while the female ones are shorter and rounder. Alder is wind pollinated, so the trees produce huge quantities of small-sized pollen grains that can float on the wind for great distances. But honey bees—as well as some other pollinators—collect the pollen to feed their young. The pollen is high in starch, so it is a good source of food energy for the developing bees.

Like most pollens, however, alder does not have all the nutrients and amino acids necessary for producing baby bees. Bees raised on alder pollen alone will not be as strong and healthy as bees raised on a variety of different pollens. Because alder pollen matures so early, it is sometimes the only pollen available—and because a colony eating nothing but alder pollen may not build up as quickly as one with a more diverse diet, alder pollen developed a bad reputation.

But it is silly to blame the alder tree. There are very few—if any—pollens that have all the nutrients necessary for bee development. Rather than fretting over the alder’s less than perfect pollen, beekeepers should celebrate its existence—over the years it has kept many a colony from biting the dust. If you want to assure your bees have a more varied diet, you can feed them a pollen patty along with the alder. In any case, it won’t be long before other pollens are available as well.

Rusty

Snacking on sugar cakes: it’s a bee thing

Rusty — Sun, 13 Feb 2011 23:11:53 +0000

Last week a reader wrote in to ask why her bees weren’t more logical. She said her hive is full of honey and a lot of it is right next to the bees. But regardless of the vast supply of honey, her bees scarfed down sugar cakes as if there were no tomorrow. Is this normal?

It is normal. Time and again I’ve watched bees eat sugar and ignore the honey. It seems as if they prefer it, although I have no idea why. Maybe it’s like a child’s preference for sweets over dinner, except that honey is sweeter than table sugar. Maybe it’s easier to eat. Maybe it melts in your mouth and not on your feet. Who knows?

The good news is that table sugar is extremely low in ash—ash being the stuff left over after you burn away a sample. In honey, the ash is made up mostly of minerals and oxides of metals.

A typical sample of honey may contain about 0.17% ash, whereas refined table sugar contains only about 0.07% ash. So that’s roughly 2.5 times as much ash in the honey as in the sugar. And of course if the honey is dark, it will contain an even greater amount of ash.

A diet high in ash is more likely to cause dysentery in bees that are not free to take cleansing flights. So while it seems like refined sugar might be an unnatural food that is not good for bees, in truth it can help them overwinter.

On the downside, refined sugar provides only energy and none of the vitamins, minerals, and other nutrients commonly found in honey. Just like our mothers told us, sugar is indeed full of “empty calories.” So for the long term health of a colony, the bees definitely need honey. But for those few short weeks between the end of winter and the first nectar flow when honey is scarce or difficult for the cluster to find, a few candy cakes will hold them in good stead.

Rusty

Honey bee forage: pussy willow

Rusty — Fri, 04 Feb 2011 17:34:37 +0000

A male pussy willow is one of the best trees for the bee yard because it will bloom especially early in the year. Beekeepers often plant them close to the apiary to help the bees through the pollen-scarce months of March and April when little else is in flower.

The term “pussy willow” refers to several species of willows that get furry gray catkins. In the states, the term usually refers to Salix discolor, a native to North America. In northern Europe it often refers to Salix caprea, although there are many others as well.

The catkins appear very early in the year before the leaves. The furry stage is actually the bud stage of the flower. Later, the fur disappears and is replaced by either male or female flowers, depending on which type of plant you have. Pussy willows are dioecious, meaning there are both male and female trees. Although only the male flowers produce pollen, both sexes produce nectar.

Pussy willows are hardy in USDA zones 4-8. In warm winters, the buds may appear as early as late February or early March. According to several sources, the nectar can be plentiful, but it may occur too early for honey bees to fly. However, many native bees—including mason, andrena, and bumble bees—are often seen happily sipping up the nectar.

The medium yellow pollen from the male trees is considered to be of average quality in terms of its nutritional contribution to honey bees, having a crude protein content between 20-25%. However, it is certainly better than nothing. If it is warm enough to fly, your honey bees will benefit from this early and plentiful source of nutrition.

Rusty

Pussy willow in bud stage. Flickr photo by Phil Sellens.

Pussy willow in flowering stage. Flickr photo by Smudge 9000.

The secret of bee tea . . . remains a secret

Rusty — Tue, 07 Dec 2010 20:37:45 +0000

A sidebar in the August 2010 Bee Culture created a lot of buzz about bee tea. The article claimed that bee tea boosts the immune system of honey bees, but it doesn’t say what in the tea helps the bees. It also doesn’t cite any studies that show a beneficial effect from its use.

Bee tea is given to bees as a feeding supplement in late summer or fall if a hive doesn’t have enough honey stores to take it through the winter. It is basically 2:1 sugar syrup made with brewed chamomile or thyme tea with the addition of mineral salt.

Now mineral salt is known to be beneficial to bees, but I’ve never read anything about the health effects of brewed leaves of any sort, so I remain skeptical.

However, the optional formula includes the addition of lemongrass and spearmint oils which have been shown in laboratory experiments to enhance honey bee health. But if you use just the sugar, salt, and tea without the essential oils, I’m not sure you are getting anything you wouldn’t get with just regular 2:1 syrup and a little mineral salt.

Nevertheless, here is the recipe that appeared in Bee Culture:

Ingredients:

16 cups white cane sugar
6 cups hot tap water
2 cups brewed chamomile and/or thyme tea
½ teaspoon mineral salt
4 teaspoons Pro Health or Honey-B-Healthy[1] (optional)

Method:

Dissolve sugar and salt in 6 cups hot water and stir until dissolved
Boil 2 cups water, pour over tea, and let it steep (covered) for 10-15 minutes
Strain tea and add to sugar solution
If using, add 4 teaspoons Pro Health or Honey-B-Healthy
Mix thoroughly
Fill feeders and refrigerate any leftovers

Regardless of any health benefits, the essential oils also help retard mold growth and fermentation in the feeders—a real plus.

Rusty

[1] These products contain lemongrass and spearmint oils with a soy-based emulsifier.

Uncapped honey fermenting in the comb

Rusty — Sun, 25 Jul 2010 17:02:27 +0000

To produce honey, bees collect nectar, add enzymes from their honey stomachs, and fan the mixture with their wings until it dehydrates to a moisture content of about 16 to 18.5 percent. If the moisture content is higher than that, the bees simply won’t cap it. If cold weather arrives before the honey is capped, it will sit open in the hive and may eventually ferment.

Fermentation is the process of changing carbohydrates to ethanol and carbon dioxide, and is no different from the fermentation process used in brewing alcoholic beverages. The yeasts that cause this biological process are found naturally in the environment and are called “wild” yeasts. The alcoholic content of fermented honey is not high—perhaps one or two percent—but knowing what to do with it is problematic.

Uncapped honey that has not fermented looks like normal honey. Once it starts to ferment, the cells are filled with bubbles and the odor of yeast can become quite rank. Sometimes foam oozes out of the cells and collects under the frames.

As a general rule, beekeepers who extract and bottle honey like to keep the uncapped cells to about 10 percent of the total. However, some go as high as 33 percent, which may require further dehydrating of the honey in order to keep it from fermenting in the bottle.

A lot of controversy surrounds the question of how harmful fermented honey is to bees and whether it can be fed back to bees. Alcohol is poisonous to them (as it is to most living things) but bees probably eat a certain amount of it in the normal course of hive life. I’m quite sure a small amount of fermented honey will not harm a hive, and many beekeepers agree.

However, if you have gallons and gallons of the stuff, I wouldn’t use it as a primary food source. Again, if you imagine bees in nature, you can see that they might encounter some fermented honey—but not barrels of it. The amount they eat should be a small part of their total diet.

Some beekeepers deal with the problem by extracting and boiling the honey which drives off the alcohol and kills many of the yeast. The downside is that boiling changes the properties of honey and increases the percentage of hydroxymethylfurfural.

For hobby beekeepers with only a few frames that contain uncapped honey, you can often give them a good shake and most of the uncured nectar will fly out of the cells. What little remains will probably not affect either the bees or the extracted honey. Use the “10 percent” rule and you shouldn’t have any problems.

Rusty

Honey fermenting in the comb. Photo by the author.

Foam dripping from fermenting honey comb. Photo by the author.

Pollen: a tough package wrapped in color

Rusty — Thu, 15 Jul 2010 16:25:45 +0000

One of the first thing beekeepers notice about pollen is its color. Depending on where you live, pollen loads come in many shades of yellow, white, orange, pink, blue, gray, and purple. And because honey bees visit the same type of flower during any one foraging trip, the pellets on their legs are the same color throughout.

In any colony the nurse bees are the primary consumers of pollen. The nurse bees digest the pollen and then secrete “brood food” from glands in their heads. It is these glandular secretions that are fed to the larvae.

Digesting pollen, however, is no easy trick. The pollen grain is designed to protect the plant’s genetic material as it is transferred from one flower to another. In order to assure the genetic message doesn’t get scrambled in transport, it is locked inside several layers:

The genetic package floats in a pool of cytoplasm. This cytoplasm is the rich food source that honey bees require.

The cytoplasm is wrapped in a cellulose layer, called the intine.

The intine is wrapped in another layer, called the exine. The exine, made of something called sporopollenin, is designed to fend off environmental hazards like ultraviolet radiation, moisture, drying, pressure, and changes in pH.

The exine is coated with a sticky substance called pollenkitt. Pollenkitt is extremely sticky and enables the pollen to stick to flowers and not blow or wash away. It is also what allows honey bees to clump it together in their pollen sacks.

As it turns out the germinal pore, the place where the genetic material will eventually be released, is the weak point in the pollen grain. Enzymes from the honey bee gut make their way through this pore and are able to digest the innards . . . sometimes.

Researches who study bee waste find that not all pollen grains are digested. Fully digested grains look like popped balloons—everything is gone except for the deflated cellulose husk. Some grains are partially deflated and some are still whole, meaning that little or none of the nutrition was extracted from those grains.

Digestibility and nutrient value of pollen grains is highly dependent on the species of flower that produced them. Foraging bees cannot tell how digestible or nutritious a pollen grain is just by looking at it, which is one reason why a varied diet is crucial to honey bee health.

Rusty

Honey bee collecting bluebell pollen. Flickr photo by OliBac.