Bee diseases – Part 5 – Parasitic Mites

Varroa destructor

Varroa destructor mites on pupae and adult bees

These are external parasitic mites that feed of the haemolymph (blood) of developing and adult bees.  Examples of the damage caused by these mites are morphological deformation, reduced lifespan, weakening of the immune system and transmission of secondary diseases (e.g. bacteria and viruses such as DWV, Kashmir Bee Virus and Acute Bee Paralysis Virus).  Varroa mites are one of the most serious pests of European bees worldwide; if infested colonies are left untreated by the beekeepers, the mites will kill the colony within 2 to 3 years.  The mites need brood to reproduce and they find drone cells more attractive to breed in than worker cells.

 

Honeybee tracheal mite (HBTM) – Acarapis woodi

Tracheal mites in honeybee trachea
Tracheal mites in honeybee trachea

Tracheal mites are endoparasitic mites and only parasitise the adult bees, affecting their trachea or respiratory system.  Heavy infestation results in sick bees that do not work as hard or live as long as healthy bees, subsequently causing weakened colonies and increased mortality.  Due to their small size, these mites can’t be seen with the naked eye and are difficult to detect.  Few tracheal mite problems have been reported worldwide in recent years.