I recently attended a bee disease day organized by the BBKA (British Bee Keepers Association). It was so informative and we were given practical classes in bee disease identification, notably European foulbrood (EFB) and American foulbrood (AFB). EFB and AFB are both bacterial contagions that effect the larvae through infected food. With EFB, the bacteria multiplies in the larvae’s gut and steals all food it is given; the larvae will then ultimately die of starvation. AFB is slightly different as it is a spore forming bacterium. Spores from the infected food germinate once inside the larvae’s stomach, then the bacteria move into the larvae’s tissue where they multiply rapidly and ultimately kill the larvae. The differentiation can be spotted with the capping of cells. Death from EFB usually occurs before cells have been capped whereas AFB deaths happen after, so the spores can stay in the hive for many years. Both diseases occur in Leicestershire so it’s always good to know what to look for!
Two highly invasive pests were also discussed, the small hive beetle (Aethina tumida) and Asian predatory hornet (Vespa velutina). Neither are currently present in the UK, but sadly it’s only a matter of time until they arrive. The small hive beetle lays its eggs in hives and the larvae will then eat honey and pollen until it leaves to pupate. Once matured, the female beetle will return to the hive to lay and the cycle begins again. All the movement inside the hive damages the comb and the larvae themselves contaminate the left over honey with faeces, causing it to discolour and ferment. Substantial infestations will force the honey bees to abandon their hive entirely and can be the indicator for Colony Collapse Disorder to be identified.
Asian Hornets are far more predatory and kill honey bees for food. Bees do have an unusual defence to attack however; they will cover a wasp and vibrate their muscles until the heat produced kills the wasp inside, a move known as heat balling. Colonies of these hornets have decimated French honey bee populations in the last few years and can be currently found in Calais. This is a big worry for the south of England as one queen can produce 1000 fertile queens at the end of each season, hence the rapid spread of this venomous, vicious insect.