Dragonflies, members of the insect order Odonata, are known for their iridescent wings and aerial agility. These insects are voracious predators, often called “mosquito hawks” because they consume large numbers of pests like mosquitoes and gnats. When one of these powerful fliers lands directly on a person, it prompts curiosity about why they choose a human as a resting spot.
Landing for Temperature Regulation
Dragonflies are ectotherms, meaning they regulate body temperature using external sources. Effective flight and hunting depend on maintaining an optimal internal temperature range. When ambient temperatures are cool, a dragonfly may seek a warm surface like sun-drenched skin or dark clothing to absorb heat, a behavior known as basking.
Conversely, intense heat risks overheating. To cool down, the insect may perch on a cooler surface, using it as a heat sink to dissipate excess thermal energy. Some species perform the “obelisk position,” pointing their abdomen toward the sun to minimize exposed surface area. The color of a person’s clothing can influence this choice, as darker fabrics attract them for warming, while lighter colors offer thermal relief.
Seeking Moisture and Essential Minerals
Beyond temperature control, dragonflies may land on a person to acquire necessary biological resources. Like many insects, they require sodium and mineral salts for proper nerve function and to support their high-energy lifestyle. While they primarily obtain nutrients from their prey, supplementary sources are often sought.
Human sweat provides a readily available source of both moisture and these essential minerals, specifically sodium chloride. A dragonfly landing on exposed skin, particularly skin moist from perspiration, may be attempting to lap up the mineral residue. This targeted behavior allows them to replenish sodium levels not sufficiently met through their insect diet.
Why They Choose You as a Perch
Dragonflies are accomplished fliers, but they require rest to conserve energy. They are territorial and hunt from a stationary vantage point, constantly seeking stable, elevated perches. A person standing or sitting still provides a vertical structure that mimics a natural perch, such as a tall reed or branch.
The height of a person offers an excellent, unobstructed view for surveying territory and spotting potential prey or rivals. A dragonfly utilizes your stillness and elevation to gain a strategic advantage. Your body is functionally similar to any other suitable natural object in the immediate environment.
Debunking Myths About Safety
A frequent concern when a dragonfly lands on a person is whether the insect poses any threat. Dragonflies are completely harmless to humans and should not be feared. They possess no stinger and therefore cannot sting under any circumstance.
While dragonflies do have powerful mandibles used to capture insect prey, they do not bite humans defensively or offensively. A bite would only occur in extremely rare instances, such as if a large specimen were handled roughly. Even in these unlikely situations, the bite is typically unable to break the skin and is not medically dangerous.