Through National Survey sampling and helping with USDA field work and forage studies I have had the opportunity to evaluate many different hives from Maryland to California to North Dakota over the past year. These hives hare both stationary and migratory, having been placed in many locations across the US, and have provided me with knowledge of different pests, diseases, conditions occurring in colonies across the country.
One such condition, first noticed in 2007, is that of entombed pollen. Amongst cells of multicolored pollen lies propolis-capped, sunken cells. Underneath this capping is bee bread, a mixture of pollen fortified with enzymes and mixed with honey, the majority of it being completely bright red in color. In some cases, only the top layer of bee bread is bright red while the under layer is of a different color variation. It is almost as though the bees recognize that there is something strange, and so they cap it over to prevent feeding.
While a ‘normal’ cell contains pollen from numerous different plant sources, entombed pollen is full of pollen husks, which provide no nutritional benefit to bees and are usually marked as a waste product, and dissolved by enzymes from honey bee saliva. Entombed pollen also has a higher percentage of the fungicide chlorothalonil which is used to control fungi on fruits, vegetables, and other agricultural crops. This fungicide is also used in paint. Sound like a something you want to feed your young if you were a honey bee? Didn’t think so!
Limited studies done on entombed pollen have shown that it tends to have a higher prevalence in older brood comb, lending evidence that the comb has collected and built up pesticide traces over time. While entombed pollen suggests something is amiss with the contents of the cell, studies suggest it is not directly responsible for colony death or CCD though colonies observed with entombed pollen do have increased mortality. More information is available about the condition and studies done on entombed pollen HERE . It is a fascinating, relatively new phenomenon that begs more research from the scientific community and observational input from beekeepers alike.