Fecal spotting in front of or on top of the colony or on nearby objects outside colonies and/or discoloration on the top bar or evidence of fecal matter on inner cover, frames, or in comb cells within colony.
Dysentery is a diarrhea-like condition in adult honey bees caused by the buildup of an excessive amount of fluid in the bee’s hindgut. It is the inability of the bee to retain waste products in the rectum. Individuals void their feces on the frames and comb, and via cleansing flights on their hive and/or in the immediate exterior of the hive. The condition of spotting of fecal matter, sometimes termed dysentery, is caused by poor food source and is most likely seen in the spring. Factors leading to dysentery can include Vairimorpha (=Nosema) disease, prolonged confinement during winter and early spring, and/or consumption of food with a high water or contaminant content. Colonies located in moist, humid areas or areas with poor air drainage may often exhibit signs of dysentery.
Oliver R. 2019. The Nosema Problem: Part 7a – The Causes of Dysentery in Honey Bees — Part 1. Scientific Beekeeping. Accessed 2023. https://scientificbeekeeping.com/the-causes-dysentery-in-honey-bees-part-1/
Oliver R. 2019. The Nosema Problem: Part 7b – The Causes of Dysentery in Honey Bees — Part 2. Scientific Beekeeping. Accessed 2023. https://scientificbeekeeping.com/the-causes-of-dysentery-in-honey-bees-part-2/