Chapter 12
Keeping Your Bees Healthy
IN THIS CHAPTER
Understanding the critical role of good nutrition
Deciding whether to medicate
Preventing problems before they happen
Recognizing the first signs of trouble
Nursing sick bees back to good health
I won’t pretend otherwise — having unhealthy bees is not the fun part of beekeeping. I’d much rather never have to think about my bees getting sick. My heart aches when they do. Nothing is more devastating than losing a colony to disease. But let’s get real. Honey bees, like any other living creatures, are susceptible to illness. The good news is that you can prevent many honey-bee health problems before they happen, and you can often head off disaster if you know the early signs of trouble.
More and more studies are showing that providing optimum nutrition for bees is one of the most significant and natural things you can do to maintain their vitality, productivity, and ability to fend off challenges to disease and other threats to their health.
Right away let me clear up one thing. None of the health problems that affect bees have any impact on human health. These diseases are 100 percent unique to your bees. They’re not harmful or contagious in any way to you or your family or their honey or other products. Phew! That’s a relief!
In this chapter, I highlight the most common health problems that your bees may face. As you inspect your hives, look carefully at the capped and open brood cells (what’s going on in these cells is often the barometer of your colony’s health). Discover how to recognize the telltale indications of health problems.
This chapter includes information about bee medications (both chemical and all-natural remedies). But medications are a subject that doesn’t stand still. New products are introduced all the time, and existing products can fall out of favor or be discontinued. On top of that, not all products are legal in all states or all countries. So medications are a moving target, and you should check with your favorite beekeeping supplier for the latest word on what’s available and how to use it.
Understanding the Importance of Good Nutrition
More than ever, good bee nutrition is critical for creating strong, healthy colonies. This is especially true given the challenges and stresses that bees face, such as decreasing availability of natural forage, pesticide contamination of food sources, parasites, and a multitude of pathogens.
What bees eat
Honey bees are vegetarians. They utilize the nectar they collect (and the honey they make from it) as their carbohydrate and energy source. The pollen they collect becomes their source of proteins, lipids, vitamins, minerals, phytochemicals, and cholesterol. Without good access to these two food sources, your bees’ overall health can suffer. And sadly, the natural sources for these are not as plentiful as they once were — urban sprawl has taken over where wildflowers once dotted the country side.
Pollen is especially critical for the larvae (to help them grow and develop), and for new adults (to kick-start their ability to produce brood food, pheromones, beeswax, and so on). Studies show bees with access to high-quality pollen have lower pathogen levels, develop more brood for successful overwintering, and are less susceptible to Nosema, the widespread gut parasite. (More on Nosema later in this chapter.)
Keep in mind that newly started colonies, colonies expanding rapidly, and colonies preparing for winter all need proper nutrition. And that is why you may need to help your bees by feeding sugar syrup and pollen substitute in the spring and autumn.
The need for good gut health
Within the bee gut, there is a soup of special beneficial bacteria (microflora) that breaks down the complex proteins, lipids, and sugars of the bees’ food into their simplest forms. Only then can the bees’ food be converted to energy that allows them to do their thing. Good gut health is an important factor in keeping your bees strong, healthy, and active. There are a number of natural food supplement products now on the market intended to enhance the bee gut health.
Taking steps to ensure good nutrition
Recent studies indicate that taking proactive steps to ensure your bees’ good nutrition is a powerful way to fight off the ravaging effects of the dreaded “Four P’s” (see Chapter 11) that can threaten a colony: pesticides, pathogens, parasites, and — you guessed it — poor nutrition.
So feeding bees sugar syrup and pollen substitute in both the spring and autumn is certainly important. But there is more you can do. These days, there are many natural food supplements on the market to further help bees’ nutrition through the use of essential oils, vitamins, minerals, probiotics, proteins, and amino acids. See Figure 12-1 for a sampling of some of the nutritional food supplements developed to keep bees healthy, vigorous, and productive.
For up-to-date information about honey bee nutrition and health, here is an informative website worth visiting: www.honeybeehealthcoalition.org.
Courtesy of Howland Blackiston
FIGURE 12-1: These are a few of the many natural food additives and supplements now on the market to help ensure optimum nutrition for your bees.
Medicating or Not?
I know what you’re thinking. Should you put medication in your hive or not? Wouldn’t keeping everything natural and avoiding the use of any chemicals, medications, or antibiotics be better? Maybe you can even save a few dollars. Or should you just take on the attitude of going for the “survival of the fittest”?
Well, perhaps the answers to these questions depend on your practice in other areas. Do you avoid taking your dog to the vet for distemper shots and heartworm pills? Would you withhold antibiotics if your child came down with bronchitis? Probably not. Bees are no different. Without some help from you, I can assure you they’ll eventually have a problem. You may even run the risk of losing your hive entirely. It need not be that way. Follow a sensible health-check regime and look carefully for signs of trouble every time you inspect your colony. If things get serious, be prepared to judiciously apply remedies to prevent losing your colonies. There are plenty of “non-chemical” treatment options, and a growing number of “all-natural” products to keep your bees healthy. Be sure to look for the All-Natural leaf icon in the margins of this book for natural methods for tending to your bees health.
Here’s the real key be thoughtful regarding medicating. Unknowingly, many beekeepers have overdone it when it comes to bee health, administering medications “just in case” they might get sick. Don’t do it. This kind of prophylactic regime has contributed to an increasing ineffectiveness of meds, antibiotics, and insecticides over recent years. If you choose to medicate, do so only when really necessary.
Remember that you should never, ever medicate your bees when you have honey on the hive that is intended for human consumption. If you decide to medicate, do so before honey supers go on the hive, or after they are removed. For a description of honey supers and their use, see Chapter 5.
Knowing the Big-Six Bee Diseases
You should be on the lookout for six honey-bee diseases. Others are out there, but these six are the most common you may face. Some are rare, and it’s doubtful that you’ll ever encounter them. Some are more commonplace (like Nosema and chalkbrood), and knowing what to do if they come knocking is important. One, American foulbrood, is very serious, and you need to know how to recognize and deal with it quickly.
Each time you inspect the brood area of your colony, you’re looking for two things: evidence of the queen (look for her, or look for her eggs) and evidence of health problems (look for the symptoms I describe later in this chapter).
American foulbrood (AFB)
I start with the worst of the lot. American foulbrood (AFB) is a nasty bacterial disease that attacks larvae and pupae. This serious threat is highly contagious to bees (not people) and, left unchecked, is certain to kill your entire colony. It’s the most terrible of the bee diseases. Some symptoms are
- Infected larvae change color from a healthy pearly white to tan or dark brown and die after they’re capped.
- Cappings of dead brood sink inward (becoming concave) and often appear perforated with tiny holes.
- The capped brood pattern no longer is compact, but becomes spotty and random. This is sometimes referred to as a “shotgun” pattern (see this book’s color-photo section).
- The surface of the cappings may appear wet or greasy.
If you see these conditions, confirm that it’s AFB by thrusting a toothpick or matchstick into the dead brood, mixing it around, and then slowly withdrawing the toothpick. Observe the material that is being drawn out of the cell as you withdraw the toothpick. Brood killed by AFB will be stringy and will rope out about ¼ inch (like pulling taffy) and then snap back like a rubber band (see this book’s color-photo section). That test can confirm the presence of AFB. Also take a close look at the dead pupae. Some may have tongues protruded at a right angle to the cell wall. There may also be a telltale odor associated with this disease. Most describe it as an unpleasant, foul smell. If you detect a foul smell and that smell lingers in your nose after leaving the hive, your bees might have AFB.
If you suspect that your bees actually have AFB, immediately ask your state bee inspector or a seasoned local “expert” beekeeper to check your diagnosis. There is also an AFB test kit you can purchase to confirm. Treatment for AFB is subject to state law in the United States. If AFB is rampant, it is likely that your hives and equipment will have to be burned and destroyed. Why such drastic measures? Sleeping spores of AFB can remain active (even on old, unused equipment) for up to 70 years.
If you are open to the idea of using medications as a preventative, these products are available (but only by prescription from a veterinarian): Terramycin or Tetra-B-Mix (oxytetracycline), Tylan (tylosin tartrate), and Lincomix (lincomycin hydrochloride). The latter two are hard to find. To administer, carefully follow the instructions provided with these meds.
Be wary of purchasing old, used equipment, no matter how tempting the offer may be or no matter how well you know the seller. If the bees that once lived in that hive ever had AFB, the disease-causing spores will remain in the equipment for decades. No amount of scrubbing, washing, sanding, or cleaning can remedy the situation. Please start your new adventure in beekeeping by purchasing new and hygienic equipment.
European foulbrood (EFB)
European foulbrood (EFB) is a bacterial disease of larvae. Unlike AFB, larvae infected with EFB die before they’re capped. It’s not as horrific as AFB, but it’s a problem that should be dealt with if you see signs of it. Symptoms of EFB include the following:
- Very spotty brood pattern (many empty cells scattered among the capped brood). This is sometimes referred to as a “shotgun” pattern.
- Infected larvae are twisted in their cells like an inverted corkscrew. The larvae appear yellowish or a light tan color and have a smooth, “melted” appearance (see this book’s color-photo section). Remember that normal, healthy larvae are a glistening, bright white color.
- With EFB, nearly all the larvae die in their cells before they are capped. This makes it easy for you to see the discolored larvae.
- Capped cells may be sunken in and perforated, but the “toothpick test” won’t result in the telltale ropy trail as described previously for AFB.
- A sour odor may be present (but not as foul as that of AFB).
Here’s the best way to view frames for diseased larvae. Hold the frame by the ends of the top bar. Stand with your back to the sun and the light shining over your shoulder and down into the cells. The frame should be sharply angled so you are looking at the true bottom of the cell. Viewed at this angle, unhealthy brood (and the queen) are often easier to spot. Most new beekeepers interpret the bottom as the midrib of the comb. It isn’t. The true bottom of the cell is the lower wall of the cell (the wall that’s closest to the hive’s bottom board when the frame is hanging in the hive).
Because EFB bacteria don’t form persistent spores, this disease isn’t as dangerous as AFB. Colonies with EFB usually recover by themselves after a good nectar flow begins. Although serious, EFB is not as devastating as AFB. There’s no medical treatment for curing EFB once it has infected a colony, although there are products on the market (such as Tetra-B-Mix) that are sold as a preventative of EFB. Tetra-B-Mix is available by prescription only from a veterinarian.
If you’ve detected EFB, re-queen your colony (to learn how to replace the old queen with a new one, see Chapter 10) to break the brood cycle and allow the colony time to remove infected larvae. You can even help the bees by removing as many of the infected larvae as you can using a pair of tweezers.
It’s a good hygienic practice to replace several frames of comb every year. There are compelling reasons for doing this: Replacing old frames/comb minimizes the spread of disease, and old wax can contain residual medication from past treatments — building resistance and making medication treatments ineffective when they are really needed.
Chalkbrood
Chalkbrood is a common fungal disease that affects bee larvae. Chalkbrood pops up most frequently during damp conditions in early spring. It is rather common and usually not that serious. Infected larvae turn a chalky white color, become hard, and may occasionally turn black. You may not even know that your bees have it until you spot the chalky carcasses on the hive’s “front porch.” Worker bees on “undertaker duty” attempt to remove the chalkbrood as quickly as possible, often dropping their heavy loads at the entrance or on the ground in front of the hive (see this book’s color-photo section).
No medical treatment is necessary for chalkbrood; your colony should recover okay on its own once weather improves and more forage resources become available. But you can help your bees out by removing mummified carcasses from the hive’s entrance and from the ground around the hive. Also, usually just one frame will have most of the chalkbrood cells.
Misdiagnosing this disease is common because it’s easily confused with chilled brood (see Chapter 9). You see carcasses at the hive entrance with both anomalies, but with chalkbrood, the bodies are hard, dry, and chalky white or gray (not a soft and translucent white or pale yellow as is the case with chilled brood).
Remove the frame containing the majority of chalkbrood mummies from the hive and replace it with a new frame and foundation. This basic sanitation minimizes the bees’ job of cleaning up. Also consider replacing your queen by ordering a new one from your bee supplier (or by providing one of your own if you are raising queens — see Chapter 14).
Sacbrood
Sacbrood is a viral disease of brood similar to a common cold. It isn’t considered a serious threat to the colony. Infected larvae turn yellow and eventually dark brown. They’re easily removed from their cells, because they appear to be in a water-filled sack. Now you know where the name comes from!
No recommended medical treatment exists for sacbrood. But you can shorten the duration of this condition by removing the sacs with a pair of tweezers. Other than that intervention, let the bees slug it out for themselves.
Do your best to keep your bees free of stressful problems (mites, poor ventilation, crowded conditions) and they’ll have an easier time staying healthy and avoiding diseases such as chalkbrood, sacbrood, and EFB. Be sure to feed them sugar syrup and pollen substitute in the spring and autumn. And consider using one of the many natural food additives to optimize their nutritional intake.
Stonebrood
Stonebrood is a fungal disease that affects larvae and pupae. It is rare and doesn’t often show up. Stonebrood causes the mummification of brood. Mummies are hard and solid (not spongelike and chalky as with chalkbrood). Some brood may become covered with a powdery green fungus.
No medical treatment is needed for stonebrood. In most instances worker bees remove dead brood, and the colony recovers on its own.
You can help things along by cleaning up mummies at the entrance and around the hive, and removing heavily infested frames (see treatment for chalkbrood). Also, feeding your bees and providing good ventilation to keep moisture under control are good basic sanitary practices.
Nosema
Nosema is the most widespread of adult honey-bee diseases and contributes increasingly to the weakening or demise of colonies. It was recently determined that there are actually two kinds of Nosema, and they are quite different from each other.
Nosema apis
Nosema apis has been around for a long time. This form of Nosema is caused by a small, single-cell parasite, but is classified as a fungus. It’s likely the kind of Nosema you will find mentioned in many beekeeping books. Nosema apis affects the intestinal tracks of adult bees — it’s kind of like dysentery in humans. It can weaken a hive and reduce honey production by between 40 and 50 percent. It can even wipe out a colony of bees. It’s most common in spring after bees have been confined to the hive during the winter.
The problem is that by the time the symptoms are visible, it has gone too far and is difficult or impossible to treat. Some symptoms of Nosema apis are as follows:
- In the spring, infected colonies build up slowly or perhaps not at all.
- Bees appear weak and may shiver and crawl aimlessly around the front of the hive.
- The hive has a characteristic spotting, which refers to many streaks of mustard-brown feces that appear in and on the hive. This is an easy-to-identify indication of Nosema apis (although other things can cause a dysentery-like condition).
You can discourage Nosema apis by selecting hive sites that have good airflow and a nearby source of fresh, clean water. Avoid damp, cold conditions that can encourage the fungus. Provide your hives with full or dappled sunlight. Creating an upper entrance for the bees during winter improves ventilation and discourages Nosema apis. Purchase your bees and queens from reputable suppliers.
Some books will tell you that it’s possible to medicate for Nosema apis prophylactically (preventively) by feeding Fumigilin-B (an antibiotic) in sugar syrup in the spring and fall. And that’s true. But scientists now know that if your bees have the other kind of Nosema (Nosema ceranae), medicating with Fumidil-B may actually exacerbate the ceranae infection rather than suppress it! At least that’s what some in-the-know folks are saying. Frankly, I feel it is best to play it safe — don’t medicate bees “just in case.”
Nosema ceranae
Nosema ceranae is the other form of the disease that has only been seen in Western honey bees since 2006. It too is caused by a single-cell parasite, and it is also classified as a fungus. But here’s where the similarities diverge. The symptoms of Nosema ceranae are not very clear, which makes it difficult to identify just by observation. For example, there is no feces-spotting of the hive. Only a microscopic analysis in the lab can confirm the presence of Nosema ceranae. But the devastation on the colony is significant, and some feel it may be a contributor to colony collapse disorder (see Chapter 11 for more on CCD).
Because information on Nosema ceranae is relatively new and treatment protocols are still evolving, it’s a great idea to subscribe to a bee journal and keep yourself informed regarding the latest news on Nosema.
A handy chart
Table 12-1 gives you a quick overview of the big-six bee diseases, their causes, and their distinguishable symptoms. It contains a description of a healthy bee colony for comparison purposes.
TABLE 12-1 Honey-Bee Health at a Glance
Situation/Disease |
What Causes It? |
Appearance of Brood |
Appearance of Brood Cappings |
Appearance of Dead Larvae |
Color and Consistency of Larvae |
How Does It Smell? |
Normal, healthy brood and bees |
Terrific beekeeping! |
Tight pattern of sealed and open brood cells |
Light tan, brown color; slightly convex; no pinholes |
No dead larvae |
Plump, bright white, wet, pearly appearance |
Fresh, sweet smell (or no smell at all) |
American foulbrood (AFB) |
A bacterium (spore-forming) |
Scattered, spotty brood pattern |
Sunken, perforated, discolored, greasy appearance |
Flat and fluid-like on bottom of cell; tongue extended to the roof of the cell |
Brown, dull, sticky, and ropy |
Unpleasant, sharp, foul smell |
Chalkbrood |
A fungus |
Scattered, spotty brood pattern |
Sunken, perforated, discolored |
Most often in sealed or perforated cells |
White and moldy; later, white, gray, or black; hard and chalk-like |
Normal |
European foulbrood (early stages) |
A bacterium |
Scattered, spotty brood pattern |
Some discolored, sunken, perforated |
In unsealed cells, in twisted positions |
Yellowish, tan, or brown |
Sour |
European foulbrood (advanced stage) |
A bacterium |
Scattered, spotty brood pattern |
Discolored, sunken, perforated |
In unsealed and sealed cells, in twisted positions |
Brown, but not ropy or sticky |
Sour |
Sacbrood |
A virus |
Scattered brood pattern; many unsealed cells |
Often dark and sunken; many perforated |
Most often with head raised |
Grayish to black; skin has a watery, sack-like appearance |
Sour or no smell |
Stonebrood |
A fungus |
Affected brood are usually white but can sometimes have a greenish, moldy appearance |
Some cappings are perforated and covered with a greenish mold |
In unsealed and sealed cells |
Green-yellow or white; hard and shrunken |
Moldy |
Nosema apis |
A fungus caused by a parasite |
Only affects adult bees |
No smell |
|||
Nosema ceranae |
A fungus caused by a parasite |
Only affects adult bees |
No smell |