To determine if something is wrong with your hive, you must first know what a healthy, productive hive looks like. Knowing what a healthy colony looks like takes time, patience, and many hours in the hive to get a feel of what is going on in the colony throughout the year. Sometime the colony does not look so great and the size of the colony starts to dwindle. You can do two things here, panic or take a look at what is actually going on. Look at the brood, look at the bees(size, wings, uniformity, behavior), look at the sealed brood, look at the food stores, look at the entrance, feel the weight of the hive, notice any odors that may be emitting form the hive, and listen to the hive. These simple things can help identify problems in the hive.
The way I learned these diseases was from my professor Dr. Robert Berthold. He had frozen frames of the different diseases that he has showed us. There were also detailed lectures on the different diseases. This was enough to get me started, but didn’t really mean much to me until I started inspecting hives for the PA Department of Agriculture where I was able to utilize the information and knowledge learned to help beekeepers diagnose problems with their honey bee colonies. Over the years I have learned a great deal more and seen many problems that I couldn’t identify but that I could at least rule out some causes. During this learning curve, I have taken hundreds of photographs of diseased bees, healthy bees and bee behavior. Recently my co-worker Mike Andree and I have started to document some of these disease and behaviors on video. In the near future we will be posting some of these videos with our experiences to help beekeepers identify problems in their hives.
Below are images I have taken comparing healthy frames of brood to ones that are not so healthy. It will cover a majority of brood diseases and other problems found in the hive. This is not a comprehensive guide; it is a collection of images displaying different diseases and symptoms within the hive to help diagnose these problems. Hopefully this will help beekeepers identify issues in their colonies.