The Four-Spotted Skimmer ( Libellula quadrimaculata) is a medium-sized dragonfly with a length of 1 5/8 to 1 13/16 inches (40 to 45 mm). Each wing is clear except for along the leading edge, which is clouded with a transparent yellowish brown. The center of each wing is marked with a small dark spot, also on the leading edge. Additionally, each hindwing is marked with a dark patch near the base. Males and females look alike, generally dark brown. The face and each side of the thorax are marked with patches of greenish yellow, and the sides of the abdomen lined with yellowish orange dashes.
Four-Spotted Skimmers are found around the world from Alaska east to Labrador and south to northern California and Texas, and from northern Europe east to Siberia. They fly early April to mid August and can be found near ponds, lakes and marshes. They feed on small flying insects. Hunting occurs from perches on twigs or rocks. This is the only Libellula species in our area in which the males do not become pruinose. Although it does not regularly migrate in North America, this species has been known to migrate in Europe, generally in 10 to 15-year cycles. The direction of the migration varies, and the migrations are thought to be triggered by a trematode parasite (it is known that several types of parasites can cause unusual behaviors in their hosts that promote the dispersal of the parasite). This species has also been known to form large swarms in Europe, often covering 100 square miles (roughly 300 square km).
After males and females mate, the female flies singly, without the male attached, to lay her eggs. She does this by dipping the tip of her abdomen in the water while hovering just above its surface.
Populations are widespread, abundant, and secure.