Common Green Darner
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This very large dragonfly has two different strategies for surviving Minnesota winters. Some common green darners migrate south, just as many birds do. Once in the south, they breed, lay eggs, and then die. Their young then hatch and migrate back to the upper Midwest in spring. The second strategy is to lay their eggs in the north with the larvae surviving the winter beneath the ice of our frozen ponds. They then emerge in spring. They are among the first of our dragonflies to reappear in spring, even when temperatures are still chilly. Many cold-blooded animals, and dragonflies are cold-blooded, have difficulty being active when the air temperatures are cold. This dragonfly, however, can shiver its wings and the large flight muscles in its thorax produce so much heat that the insect's temperature may rise to 110 degrees Fahrenheit! Watch for Behavior The common green darner pair lays eggs in tandem, with the male using the claspers at the end of his abdomen to grip the female's neck. They then fly to a pond together and alight on emergent vegetation. The female then dips the tip of her abdomen in the water, pierces a plant stem and deposits an egg. Also notice that the green thorax is translucent, permitting a careful observer to see the internal struts that brace the thorax against the power of the wing muscles. |
Common Green Darner (Anax junius) Key ID Features: 3" body. Bright green thorax. Males have bright blue tails and females, when mature, have a grayish tails. Immatures of both genders have reddish tails (see above). Present in Park: Mid-April to mid-October. Watch for them around small ponds throughout the Mississippi National River and Recreation Area. Since they migrate, they can be found in unexpected places, including the downtown metro areas. Habitat: Breeds in ponds and very slowly moving water. |
Did You Know?
The Mississippi River Basin, or watershed, drains 41% of the continental United States including 31 states and 2 Canadian provinces.