the three small unfaceted eyes that bees use to navigate using polarised sunlight.
see Open Mesh Floor
a metal mesh floor with a board underneath it to catch debris falling from the colony. Inspection of this debris can help in many ways, estimating the position of the cluster in winter, estimating the varroa burden of the colony, evaluating the effectiveness of treatment given to combat varroa etc.
when a worker bee is old enough to become a forager she flies outside the hive for the first time. She will fly a short distance out from the font of the hive and then turn through 180 degrees to face the hive. She will hover while moving to the left and right in arcs in front of the hive before flying in circles around the hive. Her circles will gradually increase in diameter as she views the hive from a variety of angles and compares its position to any landmarks. She will also void the contents of her rectum which she will not have done before, having been only ever inside. An orientation flight may last for as long as an hour. Having learned where her home is, the new forager is now able to go out to find sources of nectar and pollen and return home safely.
an organic acid, used to treat against varroa. It can be applied by trickling the acid over the seams of bees or by vaporising crystals using a heat source and so fumigating the hive. It is only effective against phoretic mites on adult bees, not against mites in capped cells, and so is generally used in winter when there is less brood and the mites are phoretic.