Lesson 8: More Common Diseases & Pests

Diseases, parasites,
and other pests
In current times, honey bees require our diligent care & attention. Long gone are the days you could set up a colony and walk away. Today, there are many stressors on honey bee colonies - lack of good year round foraging, bad location for apiary, bad beekeeping, etc. Disease & pests are just one small part of the problem - The #1 stressor - Varroa Destructor (parasite) will be covered under our next lesson, but right now I'm speaking on different diseases and pests you could find in your hives, and what you can do to help your bees.

Buying used equipment unwise unless it has been properly examined for diseases. Always best for beginning beekeepers to start with new equipment, but if buying used equipment you can cut out a sample of the brood comb and send to a bee disease lab to be tested. Cut out 4" square from center of the brood area, wrap in newspaper then plastic bag, Pack in cardboard box & mail to: Beneficial Insect Lab, Bldg. 476 Beltsville Agricultural Research Center Bee research Entomologist Room 211 10300 Baltimore Ave. BLDG 476 BARC-EAST Beltsville, MD 20705 put your return address inside and outside of pkg.

Observations: Use your senses - eyes, ears & nose...
Healthy looking broodcomb:
Bacterial Diseases

American Foulbrood
(ropey dead larvae, black scales, dark sunken cappings, distinct foul offensive odor)
This is a condition of hives caused by a spore forming bacteria called (Paenibacillus larvae). Bee larvae consume the spores which then germinate in the gut and multiply in the tissues.  Infected larvae usually die once the cell is sealed. It can be spread by robbing bees, using infected equipment and hives, and from even catching infected swarms. Prevention? Keep large healthy colonies, destroy contaminated equipment/hives. Medication? Terramycin? Terra-Pro? Tylosin? Tylan? Spores last for 50 years and indestructable.
To avoid AFB some beekeepers will routinely treat with antibiotics like Terramycin and Tylosin. However, we must all keep in mind that routine treatments with antibiotics will eventually result in antibiotic resistant bacteria and unnatural often toxic residues in honey combs. The best ways to naturally prevent AFB is to never buy used equipment and keep a hygienic hive.

European Foulbrood
(uncapped dying yellow- brown brood, sour smell, not stringy)
European Foulbrood is similar to American Foulbrood as it is a bacteria (Melissococcus pluton) that attacks brood cells. However, EFB is not nearly as detrimental. The remedy for EFB is not as extreme as burning your hives in fact, a healthy hive can at times fend off EFB. Antibiotics like Terramycin can be used to prevent EFB. In a weak hive you may want to add frames of uncapped healthy larvae from a stronger hive to attract attention from nurse bees keeping them away from diseased larvae. The characteristics of European Foulbrood include brood dying uncapped, spotty brood pattern, sunken and punctured brood cappings, brood color turns from white to a yellow-brown, brood emits a sour smell, and cells will not possess the stringy texture as that of American Foulbrood.
Fungal Diseases

(mummified, chalk white larvae/pupae on the porch)
Chalkbrood, a fungal disease of the honey bee larvae & pupae associated with low temperature and moisture stress conditions. Symptoms usually disappear with Summer - House bees are able to remove the dead larvae from their cells. (Stonebrood is another fungal disease looking similar in appearance but mummified larvae are hard to crush)

Viral Diseases

Sacbrood - SBV
(blotted larvae turn gray then black, jagged capping opening, can be removed whole by toothpick)
Sacbrood is caused by a virus (Morator Aetatulas), less destructive and less contagious then foulbrood. Can be a problem if colony short on nurse bees. It seldom becomes serious. Requeen if it persists.
Environmental Causes

Chilled Brood

Brood dies from neglect, not enough nurse bees to feed & cover (keep warm). Keep brood combs together, inspect on warm days & return brood combs quickly during inspection. I remove brood frames from hive for inpection only if temp. 60 degrees or higher.
chilled brood

Fungi Parasites

Nosema A, Nosema C
(fecal spotting)
Nosema Apis & Nosema Ceranae... Nosema C (fungi) seems to be the prevelant strain and most destructive at this time. Attacks the inner lining of the bee's mid-gut. Treatment is an antibiotic - Fumigilin-B (Fumidil-B no longer available). Feeding of the anti-biotic in sugar syrup may not be as effective against Nosema C. but Fumigilin-B added to a sugar syrup drench over 4 week period to encourage flushing of bee stomach/intestines is said to be more effective against Nosema C. (Nosema ceranae is a microsporidian, a small, spore forming unicellular parasite. They were once thought to be protists but are now known to be fungi. )
nosema c
Good accurate information from Eric Mussen U.C. Davis: http://entomology.ucdavis.edu/files/147621.pdf

Paralysis Virus

 Paralysis is a virus disease that has not caused much loss in the Northern States. It affects adult bees, appear to be partially paralyzed, tremble, look old, shiny, greasy... disease seems to be present in only onbred or non-resistant strains of bees, re-queen the colony. (Acute, Chronic, Israeli, Kashmir - all Paralysis Virus')
Other Virus' Black Queen Cell Virus, Cloudy Wing Virus, Deformed Wing Virus, Kakugo Virus, Tobacco Ringspot Virus
(opportunistic - most are related Varroa Destructor infestations)
Dysentery  Dysentery is a condition not a disease. Caused by poor quality winter stores or prolonged confinement during winter months. Also caused by Nosema A or Nosema C.
Poisoning Lots of dead bees on the door-step or in front of the hive? an organophosphate smell? Prevention: move your bees before spraying takes place. Report the incident to:
Washington State Department of Agriculture
Pesticide Management Division
877-301-4555 (toll free)

Good resource online for prevention info: http://www.step-project.net/NPDOCS/PNW%20591.pdf
            Pests of Honey Bees

Wax Moths
Wax moths are a prominent enemy of bees, but they render a service when they destroy neglected combs on which bees have dies of American Foulbrood. Two types - Greater & lesser moth. Moths do not kill bees but destroy combs not properly protected. The best way to protect combs is to give them back to the care of the bees by placing them over strong colonies.
lesser wax mothgreater wax moth
To protect supers or any comb not placed on the hives, stack in airtight pile, fumigate with PDB (Paradichlorobenzene, follow label instructions. NEVER treat with moth balls (naptha based products)

Small Hive Beetle
Adult beetles usually gather at the rear of the hive where they gather on the bottom board.
small hive beetle on bottom board

Yellow Jackets, Ants, and Earwigs
Strong colonies usually repel such insect invaders. Entrances can be reduced to assist the bees in defending the colony against aggressive yellow jackets in August & September. Still the best defense is a strong healthy colony.
yellow jacket attack

Mice can be very destructive to hives in winter and should be excluded from the hive. Keep mice out of the honey supers stored also.

Evidence of packed dirt at the entrance and muddy bottom board or feces with bee bodies in it?

Total destruction! electric fence? move apiary? shoot the bears?

Could be problem for queen rearing apiaries? Otherwise, small amount of foragers lost