Sphecius speciosuscicada killer

Geographic Range

Cicada killer wasps, Sphecius speciosus can be found in almost all parts of North America, especially in areas east of the Rocky Mountains in the United States. Cicada killer wasps can also be found across Europe. (Drees and Jackman, 1998; Grzimek, 1972)

Habitat

Cicada killer wasps dig nest tunnels in loose, sandy ground. The nests may contain multiple chambers where eggs of different females will be laid. The surface of the nest are is usually well-exposed to sunlight. Cicada killers can be found in forested areas, grasslands, and even in city parks and urban gardens. (Grzimek, 1972; Milne and Milne, 1980)

Physical Description

Cicada killer wasps range from 30 to 50 mm in length. They have a rusty colored head and thorax with bands of alternating yellow and black colors on the abdomen. Cicada killers have six legs that range from yellow to red in color. They also have large dark-colored wings. Females are equipped with a stinger at the end of the abdomen. (Milne and Milne, 1980; Alcock, 1998; Drees and Jackman, 1998; Grzimek, 1972)

  • Range length
    30 to 50 mm
    1.18 to 1.97 in
  • Average length
    30 to 40 mm
    in
  • Range wingspan
    30 to 40 mm
    1.18 to 1.57 in
  • Average wingspan
    40 mm
    1.57 in

Development

Adult female cicada killers lay their eggs in July or August. A female implants an embryo inside the body of a cicada, and stores this in a cell in the nest. The larva emerges several days later and feeds on the cicada's body for about two weeks. In the fall, the larva spins a coccoon, in which it spends the winter hibernating. The larva pupates in the spring, and emerges from the pupal stage in early- to mid-summer as an adult cicada killer. Then, it procedes to acquire food and reproduce. Males die after mating, and females die after laying their eggs. by mid- to late- August, all adults die. Each generation of cicada killers lives only a single year. (Alcock, 1998; Drees and Jackman, 1998; Milne and Milne, 1980)

Reproduction

The male attempts to attract females that enter his territory. If his courtship is successfull, then the two mate. The exact details of courtship are unknown, but it appears that one male may fertilize multiple females. (Eason, et al., July 1999; Drees and Jackman, 1998; Eason, et al., July 1999)

After mating, females begins digging a nest where they will store cicadas as hosts for their eggs, as well as food for the young cicada killers. A female paralyzes and poisons the cicada by catching it in the air and stinging it on its ventral surface. She then drags the cicada back to the nest where she deposits her egg inside it. A female will capture other cicadas, as well, and store them as food for the larva when it emerges from its host. Females have been known to work collectively to construct a single nest with multiple chambers, in which each female will store her egg and cicadas in an individual chamber. (Drees and Jackman, 1998; Eason, et al., July 1999)

  • Breeding interval
    These wasps live for a single reproductive season, and so only breed once in their lives.
  • Breeding season
    Breeding occurs from July to August.
  • Range eggs per season
    1 (low)
  • Range gestation period
    2 to 4 days
  • Average gestation period
    3 to 4 days
  • Range age at sexual or reproductive maturity (female)
    10 to 12 months
  • Average age at sexual or reproductive maturity (female)
    12 months
  • Range age at sexual or reproductive maturity (male)
    10 to 12 months
  • Average age at sexual or reproductive maturity (male)
    12 months

Female cicada killer wasps provide all the parental care for their offspring. They provide a nest and a host for the eggs to be laid in, which serves as food for the larvae when they hatch. Beyond this, adult cicada killers provide nothing for the developing young. (Milne and Milne, 1980)

  • Parental Investment
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female

Lifespan/Longevity

Cicada killers spend most of their lives inside the nest. Young do not reach maturity or leave the nest for 10 to 12 months after the fertilized cicada killer egg is laid inside the cicada. Within two months of emerging from the nest, they will mate, produce offspring, then die. (Milne and Milne, 1980; Alcock, 1998; Drees and Jackman, 1998; Grzimek, 1972)

  • Range lifespan
    Status: wild
    11 to 13 months
  • Average lifespan
    Status: wild
    13 months
  • Range lifespan
    Status: captivity
    unknown (low) hours
  • Typical lifespan
    Status: wild
    11 to 13 months
  • Average lifespan
    Status: wild
    13 months
  • Typical lifespan
    Status: captivity
    unknown (low) hours

Behavior

Male cicada killers are very territorial toward other males of the same species, and use naturally occurring geographical barriers as territorial markers. Scientists believe that male cicada killers use the buzzing of their wings to protect their territory from other males. This proposed function for buzzing is further supported by the evidence that the intensity of the buzzing is directly proportional to the body size of the cicada killer wasp. Although aggressive towards other males, cicada killer males attempt to attract females that pass through their territory. (Coelho, 1998; Eason, et al., July 1999)

Communication and Perception

The only known communication amongst cicada killers lies in the buzzing created by the wings of the cicada killer. It is believed that this buzzing is used by males to threaten other males who enter their territory. (Coelho, 1998). However, there is obviously more communication between these wasps which facilitates mating as well as the sharing of burrows by different females which has sometimes been reported. (Coelho, 1998)

Food Habits

Although adult cicada killer wasps feed on nectar from flowers, their larvae feed on cicadas. Female cicada killers hunt for cicadas and paralyze them by stinging them in the abdominal region. She then drags the paralyzed cicada back to the underground nest where it will be stored as food for the larvae. (Alcock, 1998; Drees and Jackman, 1998; Milne and Milne, 1980)

  • Animal Foods
  • insects
  • Plant Foods
  • nectar

Predation

The review of the literature did not reveal any predators of the cicada killer wasp. However, it is likely that these wasps fall prey to birds, small mammals, and other insects.

Ecosystem Roles

Adult cicada killers pollinate flowers when they gather nectar for food. Also, cicada killer wasps helps control the cicada population. (Drees and Jackman, 1998; Milne and Milne, 1980)

  • Ecosystem Impact
  • pollinates

Economic Importance for Humans: Positive

It is unlikely that these wasps provide any direct benefit to human economies. However, humans may benefit from the roles S. speciosus plays in the ecosystem. Cicada killers are pollinators and reduce annoying cicada populations. (Drees and Jackman, 1998; Milne and Milne, 1980)

  • Positive Impacts
  • controls pest population

Economic Importance for Humans: Negative

Cicada killers are capable of stinging humans, and their large size makes them appear threatening to humans. However, these wasps are very passive and rarely attacks humans. The poison associated with a S. speciosus sting is also relatively harmless to humans. Although they are relatively harmless, cicada killers are sometimes viewed as a pest by humans, especially since they disturb lawns with their nests and burrows. (Alcock, 1998)

  • Negative Impacts
  • injures humans
    • bites or stings
  • household pest

Conservation Status

Cicada killers are widespread and in little danger of extinction. Thus, currently their survival is not considered threatened. (Grzimek, 1972)

Other Comments

These interesting animals can be viewed in great detail at Professor Chuck Holliay's Cicada-Killer page. Video of many of the activities of these wasps are available there. (Holliday, 2005)

Contributors

Nancy Shefferly (editor), Animal Diversity Web.

Kelson Gist (author), Southwestern University, Stephanie Fabritius (editor), Southwestern University.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

Palearctic

living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

World Map

acoustic

uses sound to communicate

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carnivore

an animal that mainly eats meat

diapause

a period of time when growth or development is suspended in insects and other invertebrates, it can usually only be ended the appropriate environmental stimulus.

diurnal
  1. active during the day, 2. lasting for one day.
ectothermic

animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature

fertilization

union of egg and spermatozoan

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

fossorial

Referring to a burrowing life-style or behavior, specialized for digging or burrowing.

herbivore

An animal that eats mainly plants or parts of plants.

insectivore

An animal that eats mainly insects or spiders.

internal fertilization

fertilization takes place within the female's body

metamorphosis

A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

nectarivore

an animal that mainly eats nectar from flowers

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

polygynous

having more than one female as a mate at one time

scrub forest

scrub forests develop in areas that experience dry seasons.

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

semelparous

offspring are all produced in a single group (litter, clutch, etc.), after which the parent usually dies. Semelparous organisms often only live through a single season/year (or other periodic change in conditions) but may live for many seasons. In both cases reproduction occurs as a single investment of energy in offspring, with no future chance for investment in reproduction.

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

solitary

lives alone

stores or caches food

places a food item in a special place to be eaten later. Also called "hoarding"

suburban

living in residential areas on the outskirts of large cities or towns.

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

urban

living in cities and large towns, landscapes dominated by human structures and activity.

vibrations

movements of a hard surface that are produced by animals as signals to others

visual

uses sight to communicate

References

Alcock, J. 1998. Taking the sting out of wasps. American Gardener, 77 (November/December): 20-21.

Coelho, J. 1998. An acoustical and physiological analysis of buzzing in cicada killer wasps. Journal of Comparative Physiology, A. Sensory and Neural Behavioral Physiology, 183: 745-751.

Drees, B., J. Jackman. 1998. A Field Guide to Common Texas Insects. Houston, Texas, USA: Gulf Publishing.

Eason, P., G. Cobbs, K. Trinca. July 1999. The use of landmarks to define terrestrial boundaries. Animal Behaviour, 58: 85-91.

Grzimek, H. 1972. Grzimek's Animal Life Encyclopedia: Volume 2 Insects. New York: Van Nostrand Reinhold.

Holliday, C. 2005. "Professor Chuck Holliday's Cicada-Killer Page" (On-line). Accessed January 20, 2005 at http://ww2.lafayette.edu/~hollidac/cicadakillerhome.html.

Milne, L., M. Milne. 1980. National Audubon Society Field Guide to North American Insects and Spiders. New York City, New York, USA: Chanticleer Press, Inc..