SBV or Sacbrood Virus (Morator aetatulas) often appears during spring or colony buildup and causes larval death. The pupa fails to pupate and has a “shrunken head” appearance. When you see perforations in the sealed brood with the infected larvae inside, the perforation is usually choppy or jagged indicating a problem. If the SBV pupa is totally open, the capping has been completely removed by bees and the pupa is most likely greyish-yellow to brown and starting to dry out. When removed the pupa looks similar to a slipper or canoe. Infected adult bees will have decreased life spans. Symptoms: • Perforated sealed brood, pupa…
Author: Rob Snyder
I currently work out of the Butte County Cooperative Extension in Oroville, CA as a Crop Protection Agent. I received my B.S. in biology from Delaware Valley College, PA. There I attained a majority of my entomological knowledge from Dr. Chris Tipping and Dr. Robert Berthold. After graduation, I was an apiary inspector for 2 years at the Department of Agriculture in Pennsylvania. In my third year there, I still inspected some colonies but I mainly focused on The Pennsylvania Native Bee Survey (PANBS) where I pinned, labeled, entered data and identified native bees to genus species. Leo Donavall assisted me in learning the basics on positive Identifications of the native bees. Around the same time I began working on coordinating kit construction and distribution for the APHIS National Honey Bee Survey. I was also fortunate to conduct many of these surveys with fellow co-worker Mike Andree and Nathan Rice of USDA/ARS throughout California. All of these experiences have led me to where I am today, working to assist beekeepers in maintaining genetic diverse colonies resistant to parasites while reducing the use of chemical treatments in colonies. The BIP Diagnostic Lab at the University of MD is in an integral part of this process by generating reports in which we can track change and report to beekeepers vital information in a timely manner which may influence their treatment decisions.
American Foulbrood (AFB)
How does AFB spread? American Foulbrood (Paenibacillus larvae) is introduced to the hive by drifting bees from nearby colonies, infected equipment/tools, beekeepers and robbing. The infection begins when spores enter the hive, and then food contaminated by spores is fed to the larvae by nurse bees. Once spores are in the midgut the bacteria take over using the larvae as a source of nourishment. After the cells are sealed, death occurs. If death occurs while in the pupal stage, there may be a protruding tongue present. When there is a serious infection you can notice moisture on sealed brood as they start to sink. Sunken…
Parasitic Mite Syndrome (PMS)
PMS or Parasitic Mite Syndrome is a condition that causes a honey bee colony to deteriorate and eventually dwindle away and die. There has not yet been a pathogen detected which causes the brood symptoms that appear with this syndrome. However there are always varroa mites present with this syndrome. The brood symptoms look similar to other diseases but the larvae don’t rope. Colonies with PMS will show symptoms of white larvae that are chewed or pecked down by workers. Larvae may appear sunken to the side of the cell and may show symptoms of white with some debris at the posterior end. Pupa will…
Bald Brood video
In April 2013 I wrote a blog about Bald Brood. Since then I have captured a video of myself digging out the wax moth larvae from the sealed brood. Whenever I see these symptoms I always try to remove the wax moth. For more information on bald brood please see my previous blog HERE. http://youtu.be/5ALPbxLnpJI
Neglected Drone Brood
Throughout the year several honey bee diseases can be noted in stressed or sick colonies. There are also other stress factors that cause colony conditions to deteriorate and look very similar to sick or diseased colonies. One condition is neglected drone brood. It is caused by either a drone laying queen, laying workers, poorly mated queens, or failing queens. The size of the colony will determine how long it takes to dwindle down and show signs of neglected drone brood. Most of the photos are from a colony that had a poorly mated queen. The symptoms appeared 10 days after she started to lay. In…
Bald Brood
An interesting brood symptom you may come across in a weak hive in the spring is Bald Brood. Bald brood is caused by the Lesser wax moth (Achroia gresella) or the Greater wax moth (Galleria mellonella.) You can see in the image below the linear pattern of uncapping that occurs due to the wax moths tunneling behavior. These symptoms can sometimes be confused as hygienic behavior; I have included an image showing some hygienic behavior of uncapping. One visible difference between hygienic behavior vs. bald brood is that there is no linear pattern of uncapping sealed brood with hygienic behavior. Colonies with bald brood often…
Unknown Brood Damage
Posted 4/17/2013 This blog was changed from the original post. The title has changed from Pesticide brood Kill to Unknown Brood Damage. This change was in response to the comments I have received both on this blog and by emails, I want to clarify a few of my comments. First, I regret the original title of the blog as correctly noted; I had no concrete evidence that it was a pesticide brood kill. No pesticide analysis was done on the pollen or bees because, as I mentioned in the comments section, this beekeeper knew what was being sprayed, when it was being sprayed and the…
European Foulbrood (EFB) Part 2.
The most problematic pest beekeepers encounter in the United States today is the varroa mite. The varroa mite (Varroa destructor) is an ectoparasite associated with spreading disease, pathogens and reducing the lifespan of male and female honey bees. The mites accomplish this by creating wounds in honey bees with piercing/sucking mouthparts, then feeding on the hemolymph within. Research suggests that these mites transfer single-stranded RNA virus between bees, along with infections of bacteria, including Melissococcus pluton (EFB). This type of bacterial infection of larvae or pupa is considered a secondary infection, since the mite initiated the process and the bacteria followed. EFB is normally transmitted…
How to make a Sugar Roll jar
A sugar roll test is a simple way to monitor your varroa mite loads without killing a lot of bees. It is easy and fast and only a few items are needed. To make a sugar roll jar you will need a few supplies. You can get these supplies at a home improvement store and the grocery store. • Wide mouth quart canning jar with a two piece lid. You can use other sized jars as long as there is a two piece lid. • Screening-#8 mesh (8 squares per square inch) is preferred but you can use other screening as long as it allows…
Spring Sampling in Northern California 2013
Sampling large numbers of beekeepers takes considerable behind-the-scenes planning and work and this aspect of the project usually goes unseen and is underappreciated. I want to shed some light on what we all do to prepare for a hectic and fast-paced sampling season. Our spring sampling kits arrived from the east coast in several boxes. Team member Karen Roccasecca in Pennsylvania put the kits together consisting of a labeled alcohol bottle and virus sample bottle in individual bags. The individual bags contain both bottles and were grouped in 12 then placed into larger bags and eventually boxed. She then shipped them to our team at…