Blue Dasher Dragonfly

The blue dasher is a small, abundant dragonfly found around still and slow-moving water across most of the United States, southern Canada, and Mexico. Mature males are easily recognized by their chalky blue abdomen paired with vivid green eyes and a striped green-and-black thorax.

This species is frequently observed perched horizontally on twigs or reeds near water, often holding its abdomen raised toward the sun in a posture called obelisking, which is thought to help regulate its body temperature in hot weather.

• Small to medium dragonfly, body length about 2.5–3.2 cm
• Mature males have a chalky blue (pruinose) abdomen, bright green eyes, and a green-and-black striped thorax
• Females and immatures have a brown-and-yellow striped body without the blue pruinescence
• Wings often show a small dark patch at the base
• Distinguished from other blue-bodied skimmers by its smaller size and bright green eyes

Found around still or slow-moving water including ponds, lakes, marshes, and ditches across most of the United States, southern Canada, and Mexico, often in disturbed or man-made water bodies as well as natural wetlands.

Perches horizontally on twigs, reeds, or rocks near water, frequently adopting an upward-pointing 'obelisk' posture with its abdomen raised toward the sun to help regulate body temperature. Feeds on small flying insects captured on the wing. Males defend small territories over water and display to attract mates.

Eggs are laid in water among aquatic vegetation. Aquatic nymphs prey on small invertebrates, including mosquito larvae, developing over a period of several months. Nymphs emerge from the water and molt into winged adults during the warmer months, with multiple generations possible per year in warmer climates.