Size
12-14mm for workers, 18-20mm for the queen
(1)Identification
Black with white markings on the head, thorax, and the last few segments of the abdomen (male with white on the first abdominal segment)
(1). Wings smoky.
A large black and white yellowjacket with brown eyes (FigA). The 1st 3 terga are usually entirely black (Figs J, N). Recognizable as a Dolichovespula by the large gap between the mandible and eye (oculo-malar space) (FigB)
A
B
Variations:
Queens (FigC) and workers (FigD) may have lateral pale spots on the 3rd abdominal segment, and, rarely, isolated white spots on the 3rd tergite (FigE). Males may have a pale band on the posterior end of the 1st tergite and pale stripes on the posterior end of the 3rd (FigF)
The pale lateral stripe on the pronotum of the thorax can vary from relatively narrow (FigG) to broad (FigH, H1).
Sexual dimorphism
Males have long antennae with 13 segments whereas females (queens and workers) have only 12. Males also have a 7-segmented abdomen with white patches on segments 4-7. Female abdomens are 6-segmented with white dorsal patches on 4-6 (FigI). Queens are larger than workers and males (FigJ).
IJ
Currently, Queen images include Figs. A, C, E, H, H1
Worker images include Figs. D, G, and
Male images in the Guide include Figs. B,F,and
Range
Throughout North America
(2), but absent from the dry mid-west. Click on "Data" in menu bar above to see the states/provinces where we have images of this species.
Habitat
Nests are built above ground in trees, bushes, and other protected places.
Baldfaced Hornets make large oval nests (when mature) above ground with the entrance low down on the side (FigK). However, the beginning nest by the queen is globular with the entrance at the bottom (FigL).
K
L
Season
Fertilized queens overwinter, workers present from Spring to late Fall, new queens and males produced late Summer/Fall. It is possible that colonies are active all year in the deep south. Click on "Data" in menu bar above to see the states/provinces/months where we have images of this species.
Food
Adults are common on flowers
(1)(Figs D,F,G,I) where they drink nectar
(2). Adults feed pre-chewed insects to larvae
(2). Also are carnivorous and eat fruit:
A fertilized queen overwinters and starts a paper enclosed nest in the Spring. As the colony grows, multiple tiers are added, consisting of hexagonal cells. Males appear in the Fall.
Remarks
Arnett places
maculata in the
Dolichovespula subgenus
(1), but others, including Akre et al.,treat
Dolichovespula as a genus
(3)(4).
Papp has good illustrations (fig. 1726) comparing the abdominal markings of the male, queen, and workers.
(4). Image also in the Guide, see above under Sexual Dimorphism.
Similar Species
Three other yellowjackets that are basically black and white can be confused with the Baldfaced Hornet. These are: White Yellowjacket (D. albida), Northern Yellowjacket (D. arctica), and the Blackjacket (V. consobrina). Queens of the latter 2 species are compared with a Baldfaced queen (Fig M). One difference between the Baldfaced and the other 3 species is that in the former segment 2 is always all black (Fig N lateral view of the 3 castes of the Baldfaced Hornet)), in the other 3 there is a pale band on the posterior of segment 2.
MN
See syrphid fly below:
See Also
The syrphid fly:
Spilomyia fusca is a mimic of the Bald-faced Hornet:
Print References
Akre et al., 1981. The Yellowjackets of America North of Mexico. See under Books in Vespinae in the Guide for details.
