Eversion of the Honey Bee Drone Endophallus for Insemination


Instrumental Insemination of Honey Bee Queens


Diagram of honey bee queen insemination from Sue Cobey’s fact sheet, “Insemination of the Queen”


Insemination Techniques

  1. Eversion of the Honey Bee Drone Endophallus for Insemination
  2. Semen Collection for Artificial Insemination in Honey Bees

    1. Saline Recipe
  3. Insemination of the Honey Bee Queen
  4. Field Dissection of the Honey Bee Queen Spermatheca


UC Davis bee breeder-geneticist Susan Cobey with a frame of banked queens. (Photo by Kathy Keatley Garvey, UC Davis Department of Entomology)


These pages are brought to you by Susan Cobey at www.honeybee.breeding.com

For classes in instrumental insemination by Susan Cobey, see: The UC Davis entomology website



To obtain semen, eversion of the endophallus is a two-step process, the partialand full eversion. To induce the partial eversion, grasp the head and thorax of the drone between the thumb and forefinger, ventro-dorsally. Roll or crush thethorax between your fingers. The abdomen of mature drones will contract and a pair of horn like, yellow-orange cornua is exposed. If the abdomen remains soft or the cornua are clear, lacking color, the drone is immature and will not yield semen.


Mature Drone


Immature Drone



To expose semen, the partial eversion is completed by stimulating further contraction of the abdominal muscles. The buildup of pressure and compressionof hemolymph and air sacs force the full eversion of the endophallus. Grasp thebase of the dorsal abdomen close to the thorax, with the thumb and forefinger.Apply pressure along the sides of the abdomen, starting at the anterior base andworking toward the posterior tip. Squeeze and roll your fingers together in onesteady forward motion, forcing the complete eversion. The endophallus will flip up with force, exposing semen. Hold the drone downward to avoid contamination with your fingers.



The two steps of the eversion process are preformed within a few seconds. The exposed semen is a creamy, marbled color,with an underlying bed of white mucus. Young drones may have only a thin layer ofsemen. The semen of older drones is darker, more tightly clumped and easier to separatefrom the mucus. Have a plentiful supply ofmature drones, as not all will yield semen.Keep drones warm and well fed. Inactive drones are difficult to evert and perish quickly.

Download a .pdf: Eversion of the Honey Bee Drone Endophallus for Insemination

EN Español : Eversión del Endofalo del Zangano