Dolichovespula maculata

Taxonomy

Order: Hymenoptera
Family: Vespidae Laicharting, 1781
Subfamily: Vespinae Laicharting, 1781
Genus: Dolichovespula Rohwer, 1916
Species: Dolichovespula maculata (Linnaeus, 1763)
Common names: bald-faced hornet, bald hornet, white-faced hornet, black jack, white-tailed hornet, spruce wasp, and blackjacket

Background

Dolichovespula maculata is a large black and ivory-colored yellowjacket. It has adapted to living in close proximity to humans and can be found well within city boundaries. It is less aggressive than other members of Dolichovespula (Akre et al. 1981)(Akre et al. 1981):
Akre RD, A Greene, JF MacDonald, PJ Landholt amp; HG. Davis. 1981. Yellowjackets of North America, North of Mexico. U.S. Department of Agriculture, Washington, D.C. Handbook #552..

Distribution

Dolichovespula maculata occurs throughout North America and has been collected in every state and Canadian province (Kimsey and Carpenter 2012; Akre et al. 1981).

Diagnostic characteristics

Dolichovespula maculata is easily recognized by its black and white coloration, which differs from its mostly yellow and black congeners.

To identify the genus:

• malar space malar space:
  or malar area; the shortest distance between the base of the mandible and the lower margin of the eye
  long, one fifth eye height or longer
• pronotal carina present, broadly interrupted medially (Kimsey and Carpenter 2012; Buck et al. 2008)

To identify the species:

• coloration black and ivory
• metasomal tergaterga:
  the segments on the top side of the abdomen, often abbreviated when referring to a speciifc segment, such as T1, T2, etc.
  1–3 black, without pale apicalapical:
  near or at the apex or end of any structure
  bands, tergumtergum:
  the segments on the top side of the abdomen, often abbreviated when referring to a speciifc segment, such as T1, T2, etc.
  3 usually with pale laterallateral:
  the side
  spot
• hind tibiatibia:
  the segment of the leg, between the femur and the tarsus
  black, at most with small pale spots near basebase:
  the foundation of a structure
  and apex
• female usually with an uninterrupted pale postocular band
• apex apex:
  end of any structure furthest from the head
  of male metasomal sternumsternum:
  the plates on the underside of the abdomen, often abbreviated when referring to a specific segment, like S1, S2, etc.
  7 with a pair of pointed teeth
• workers 12–14 mm long (0.5–0.6 inches)
• Queens 18–20 mm long (0.7–0.8 inches) (Buck et al. 2008)(Buck et al. 2008):
  Buck M, SA Marshall, amp; DKB Cheung. 2008. Identification Atlas of the Vespidae (Hymenoptera, Aculeata) of the northeastern Nearctic region. Canadian Journal of Arthropod Identification 5: 1ndash;492.

Biology/Life cycle

Like other yellowjackets, Dolichovespula maculata forages for prey such as insects and has even been known to attack small birds. Unlike hornets in the genus Vespa, this species does not scavenge for dead insects or meat (Heinrich 1983)(Heinrich 1983):
Heinrich B. 1983. Strategies of thermoregulation and foraging in two vespid wasps, Dolichovespula maculata and Vespula vulgaris. Journal of Comparative Physiology B 154: 175ndash;180..

Dolichovespula maculata builds aerial egg-shaped nests 1.1–20 m above ground, usually in trees and shrubs, but sometimes under rock overhangs and on buildings. Annual colony initiation is usually mid-May, workers emerge in mid-June, first queens emerge in mid-August, and colony termination happens in mid-September. New queens overwinter until they emerge in the warmer weather the following spring. At higher latitudes colony initiation is delayed until June (Archer 2006)(Archer 2006):
Archer ME. 2006. Taxonomy, distribution and nesting biology of species of the genus Dolichovespula . Entomological Science 3: 281ndash;293..

May be confused with

Dolichovespula arenaria

• D. maculata is ivory and black, while D. arenaria is yellow and black
• D. arenaria metasomal tergaterga:
  the segments on the top side of the abdomen, often abbreviated when referring to a speciifc segment, such as T1, T2, etc.
  1 and 2 possess broad yellow bands that expand medially into sharp, triangular projections (Kimsey and Carpenter 2012)(Kimsey and Carpenter 2012):
  Kimsey LS amp; JM Carpenter. 2012. The Vespinae of North America. Journal of Hymenoptera Research 28: 37ndash;65. Doi.org/10.3897/jhr.28.3514.

Dolichovespula arctica

• D. arctica metasomal tergaterga:
  the segments on the top side of the abdomen, often abbreviated when referring to a speciifc segment, such as T1, T2, etc.
  1–3 with pale markings, while D. maculata tergaterga:
  the segments on the top side of the abdomen, often abbreviated when referring to a speciifc segment, such as T1, T2, etc.
  1–3 are entirely black (Kimsey and Carpenter 2012)(Kimsey and Carpenter 2012):
  Kimsey LS amp; JM Carpenter. 2012. The Vespinae of North America. Journal of Hymenoptera Research 28: 37ndash;65. Doi.org/10.3897/jhr.28.3514.

Known introductions

none