I can’t improve on the NBU’s advice – so here it is.
Before inspecting, familiarise yourself with the differences in appearance between healthy brood and diseased brood. Consider bringing a smartphone with you into the apiary to assist with identification.
• Wear a clean bee-suit and have a lit smoker close to hand. Make sure the smoker is placed in a safe location away from meltable items such as polystyrene, or dry vegetation that might catch fire.
• Inspect the ground outside the entrance and the removeable Varroa floor (if inserted) for signs of dead/diseased bees or brood; the nurse bees will remove some of them from the hive (Figure 22).
• Remove the hive roof and place it upturned on the ground behind the hive, close to where you are working. Place it so that it does not block your exit route or constitute a trip hazard if you need to leave the hive for a moment.
• If there are supers on the hive, place them on top of the upturned roof. Keep the crown board over the supers to prevent robbing.
• Be gentle when prizing the boxes apart, banging or bumping them will aggravate the bees.
• Remove the queen excluder and check the underside for the queen. If she is present, place her back into the colony, or into a queen-cage for safekeeping for the duration of the inspection. Place the queen excluder upturned on the supers.
• If you have two brood boxes, place the top brood box above the queen excluder on the supers while you inspect the bottom box (the queen excluder will prevent the queen from escaping from the underside of the brood box).
• To begin inspecting a brood box, gently remove the outer most frame (or dummy board) closest to you, being careful not to roll the bees against the side of the box as you lift the frame out. Check that the queen is not on it before putting the frame aside so that you can operate inside the brood box.
• Use your hive tool to gently prize apart frames that are stuck together. A gentle approach is recommended to prevent aggravating the bees. Examine each frame in series, one at a time, placing it back into the box in the same orientation it was in when you took it out; but leaving space to lift out the next frame without rolling the bees.
• Methodically examine one frame at a time. When you find a frame of brood, it will be necessary to shake off the bees if you wish to inspect the brood. This will allow a thorough examination, to look for signs of disease and to find swarm cells.
• To shake off bees hold the frame by both lugs, lower the frame one third the way into the hive and give the frame a sharp downward jolt into the hive, being careful not to bang it against the box or other frames. It may take some practice to do this in a way that clears most of the bees from the frame.
• Check that all stages of brood are present. If there are no eggs and young larvae, this indicates a problem with the queen.
• Carefully check that the brood cells look healthy. Larvae should be ‘C’ shaped and pearly white and capped cells should be dry and biscuit coloured. Read the foulbrood advisory leaflet to learn more about brood diseases.
• Check the frames for signs of queen cells. It is important to learn the difference between swarm cells and emergency queen cells and act accordingly.
• Consider photographing anything that you are concerned may be abnormal. You can study the photos carefully indoors and show it to a mentor if you have concerns.
• Continue until all frames have been examined and gently reassemble the hive. Do not forget to return the queen to the hive if you have caged her during the inspection and to place the last frame (or dummy board) back into the hive so that all the frames have the correct bee spacing. Be careful to replace the queen excluder back in the correct orientation.