Reading Brood Frames?

By Dr. Dewey M. Caron

Editor’s Note: The updated edition of Dr. Caron’s book, Honey Bee Biology & Beekeeping, is now carried by Kelley’s. This edition is in full color and has all the newest information in it. It is unique in that it extensively covers both the biology and the beekeeping for those “students” of the honeybee. Dr. Caron noted “Individuals constantly tell me they return again and again to the book to re-read it and find they can get the information they need on bees and/or their biology from the one source.”

At Kelley’s Field Day, I did a workshop on READING BROOD FRAMES. This is a good workshop that works as a great educational activity for a bee meeting talk or for an Open Hive event. It is designed to introduce the concept that we should ask what the bees are trying to communicate to us when we enter their brood chamber, by “reading” the brood frame.

It is important for beekeepers to create as little disturbance as possible when opening and inspecting hives. Every time we open the colony, we disrupt their normal routine (think of someone bursting into your house, moving the furniture around, bringing full sunlight and a stinky smoker—you would be “disturbed” too).  Such disturbance often carries over to another day depending upon the weather conditions when we open and how long we have the colony open. Good bee stewardship should seek to create as little disturbance as possible while we seek to figure out what the bees are doing.

We get our information by “reading the frame” every time we pull a frame from the brood chamber. Frame reading takes experience and skill. When in the brood chamber we should determine if the colony is queenright, if the brood is healthy, and assess if the colony is expanding (spring,) stabilized (summer) or contracting (later fall/winter) in brood/adult populations, as appropriate. A practiced reading means determining what the bees are communicating to us.

Sometimes we can “read” the colony by inspecting two or three frames—some colonies take longer and we need to inspect additional frames to find our answers. Seldom do we need to look on every frame in every box. Experience will improve this reading skill. Knowing where and of course what to look for is the skill we should refine.

In our routine brood chamber inspections we seek to determine if our colony is “QUEENRIGHT”—not by spending time looking for the queen but rather by seeing normal egg laying. Eggs and their “normal” positioning “tell” us a queen was in this colony within the last three days. (Review the last Newsletter for a summary of what I say about our “need” to see the queen, in A-Bee-Cs page 21.)

Looking at capped brood we should evaluate the extent of the pattern, the completeness, and if the capped cells look normal. We need to know “normal” so we can diagnose abnormal. We should recognize the larger drone cells, where the queen must lay unfertilized eggs. We cannot tell the difference between fertilized and unfertilized eggs but bees sure do! 

Looking at larvae we can diagnose the early symptoms of colony decline. Spotty brood patterns are often the first clue and then on closer examination we can see unhealthy larvae. In addition to pattern and extent of “open” cells, we should look for off-color, twisted larvae. Sometimes an off-odor can be detected, even upon opening a colony. 

Skillful beekeepers look to see a ratio of 1:2:4 in the brood chamber (for every egg, 2 larvae can be seen and 4 times the number of capped cells will be present) and a covering mantle of adult bees. Such a “read” takes skill and practice. With CCD and heavy mite damage, this ratio and the coverage of adult workers is not properly balanced. Neglect of brood may be evident, especially at the margins of the spherically-shaped brood chamber. Some cappings may be perforated (an AFB symptom) but hopefully inside, a developing adult will be found rather than a broken down, foul-smelling larva or prepupa. 

Determining whether a bee colony is increasing versus decreasing in population is not always an easy read. Also determining the amount of honey and pollen present as appropriate for the season takes practice in evaluation. Most commercial operations equalize colonies so all the units on a pallet are more or less the same in strength. If diseased brood is present, this management unfortunately serves to spread the disease condition, not contain it.

The brood is trying to “tell” us something, but are we prepared to “read” the brood to find “answers”? Here is how you can give a workshop to help with this skill.

The Workshop Concept

In an Open Hive event, pull out a brood frame and ask individuals to point out capped brood, capped honey, ask if drone cells/capped drone cells are present, ask if eggs are present, and ask if pollen is present and if they see queen cells or cups. In an inside meeting do the same with a frame projected onto the screen; add the initials after someone in audience points out the location to be sure everyone “reads” the same thing. 

Example of a brood frame from a hiveHere is such a frame. Mark capped brood (CB), capped honey (H), pollen (P), eggs (or where to look for them) (E), drone cells/brood (D), queen cells/cups (QC), and finally any signs of brood disease. It will of course be hard to see eggs (even in Open Hive workshop) and there may be no drone brood, pollen (if frame is full of capped brood for example), or queen cells—queen cups might be more commonly present.

The “Reading the Frame” Quiz

I then go through five options to which I ask for YES, NO or MAYBE response (have them all shout it out or call upon individuals) for eggs, pollen and drone cells and/or queen cells/cups (whichever might be appropriate).

What if there are NO EGGS present on this one frame? Does that mean…


  • no queen present

  • new virgin/newly mated queen present—not laying eggs yet

  • look on another frame—this one filled with cells of mostly capped brood

  • end of season or drought conditions or pollen resources no longer available

  • bees preparing to abscond (or swarm)


What if no pollen evident (on this one frame)? Does that mean…

  • no young brood to stimulate pollen foraging

  • numbers of cells filled with fresh nectar

  • no space—look on another frame especially frame at edge of brood sphere

  • pollen dearth or drought or heat spell

  • bees preparing to abscond (or swarm)


(NOTE: There are no YES or NO answers; all are MAYBE, but the most likely answer is the middle one.)

What if there is no drone brood (or queen cells) on any frames? Does that mean…


  • end of foraging season

  • pollen dearth or drought or heat spell

  • look on another frame—no space here

  • look again at margins of frames and at comb between boxes

  • not rearing queens (cup presence OK) because __________________


(NOTE: all answers are possible—depending upon frame, middle answer is again the best one.)

Finish after this exercise by asking is the colony queenright? This will get into discussion “Do you need to see the queen?” See the July, 2013 Kelley newsletter (page 21) for some pointers on how to handle this discussion.

I usually summarize the discussion by saying NO—seeing eggs is easier and gives just as much information unless we are re-queening/splitting or need to confirm continuation of special stock. Beekeeping is not rocket science; we don’t have to get it perfectly right. It takes time and skill to find a queen and routinely looking for her usually results in unnecessarily long hive openings, potentially causing greater colony disturbance. 

And finally, if time permits, ask (on basis of this one side of one frame): “Is the brood healthy?” ANOTHER good finish would be to ask “Is this amount of brood and honey/pollen stores appropriate for the season?” You will need good beekeeping skills to help lead such discussions. Be mindful that some individuals will have different opinions.

“Reading the frame” is a fun and educational exercise. Try it with your family, friend or club members. This exercise will definitely help you to learn as you teach others!

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