Cicada Killer - Sphecius speciosus

NutritionCopyright permission from Lee Townsend

Wasps are thought to be very beneficial for humans. One major benefit that wasps provide is keeping the population size of many insects at a controlled level. Another benefit that humans see is the pollination of flowers (Drees and Jackman, 1998).

Mature cicada killers eat fermented sap from large plants. Sap is the insect's primary source for water and carbohydrates (Clark, 1937). Cicada killers will pollinate flowers as they move from one to another gathering food (Drees and Jackman, 1998).  Immature cicada killers are carnivores feeding on cicadas. Young are brought paralyzed cicadas by their mothers to feed on.  Sphecius speciosus are known to hunt thirty species of cicadas (Holliday and Coehlo, 2009). Because cicada killers are usually smaller than the cicadas that they prey upon, cicada killers will climb back up a tree so that they can glide back to the nest with the prey on their back.  Larger sized cicada killers are shown to be more successful in bringing large cicadas back to their nests. The larger size allows some Sphecius speciosus to be allowed safe flight despite having prey on their back, or at least a more successful trip dragging on the ground. Cicada killers at times have been seen abandoning paralyzed cicadas due to difficulty transporting them back to the nest (Coehlo, 1997).  In instances where there are no tall objects to glide from, dragging the food back to the nest is the only option (Holliday and Coehlo, 2009).

The sting from a female cicada killer is not fatal; it simply puts the cicada in a coma-like state.  The paralyzed cicada is placed in the nest alive being fed upon by larval cicada killers (Marlos, 2010). A study done in 1979, showed evidence that the size of cicada prey has a correlation to the size of cicada killers.  Immature females are frequently given larger, and more cicadas leading to the mature cicada killers to be larger in size than males (Lin, 1979).   As the young feed, they first eat the unnecessary body parts from the cicada, leaving vital organs for later meals.  After the entire cicada has been eaten, the larva begins to prepare itself for winter inside the nest.  Young Sphecius speciosus will emerge usually around July to start the next generation (Marlos, 2010).