The dragonfly dates back at least 320 millions years, long before dinosaurs roamed the earth. Today nearly 5,000 types are known worldwide. Maryland is home to 180 species – some of which are globally or regionally rare.
Dragonflies are actually two closely-related groups of insects: damselflies and true dragonflies. Dragons tend to be larger, more robust and stronger fliers; they typically extend their wings horizontally. Damsels are comparatively small, dainty in appearance and weaker fliers; their wings are usually lifted vertically and folded together above the body. They feed on a variety of mosquitoes, midges, and black and deer flies. They do not sting, and given their small mouths, their bites are seldom painful.
Dragonflies spend the vast majority of their lives as larvae so habitat is critical to maintaining healthy populations. Female dragonflies lay their eggs in or near water or in places that eventually become saturated, such as tree cavities. They often choose wetlands void of fish to protect larvae from predators – fish, salamanders, turtles and water birds.
Dragonflies rank among the most imperiled species in North America. In Maryland 60 percent are considered rare or uncommon – including the treetop emerald, the jewel wing and the blackwater bluet. Long regarded as excellent barometers of environmental health, their demise is an indication of the state of our aquatic resources.
The greatest threat facing dragonflies is suburban sprawl and urbanization; drastic landscape and environmental changes that accompany development can devastate aquatic ecosystems, rendering them unsuitable.
Photo of Slatey Skimmer (Libellula
incesta) courtesy of
Photo of Argia alberta courtesy of Richard Wiegand