Enallagma ebrium
(Marsh Bluet)


Order: Odonata
Suborder: Zygoptera
Order Description:
Damselflies
Family: Coenagrionidae
Family Description: Bluet

Description:
   Naiad- This is a small naiad about ¾ to 1 inch (16 to 20 mm) long. It has the typical slender shape of immature damselflies. They range in color from light to dark brown.
   Adult- This is a small damselfly about 1 to 1 ¼ inches (26 to 33 mm) long. The males are predominately blue on the sides of the thorax, and the upper side of the abdomen. Both the upper and lower anal appendages are about the same length. Females are greenish-yellow to brown. The upper side of the abdomen is mostly black. Segment two has a stripe on the upper side that widens at the base.

Range:
This species is found across the continent from southern British Columbia east to Nova Scotia and south to Utah, Nebraska, and Virginia. In Idaho it is known only from the northern half of the state.

Habitat:
This damselfly occurs at lowland lakes, ponds, and marshes, and has a definite preference for alkaline waters.

Adult Flight Season:
June 11 to July 8

Diet:
   Naiad- Naiads eat a wide variety of aquatic insects, including mosquito larvae, mayfly larvae, and other aquatic fly larvae.
   Adult- Adults eat a wide variety of small soft-bodied flying insects, such as mosquitoes, mayflies, flies and small moths. They will also pick small insects such as aphids from plants.

Ecology:
This species is very common at alkaline marshes in mid-summer.

Reproduction:
The males set up territories at choice breeding sites. After males and females mate, the female Marsh Bluet oviposits, or lays eggs, either singly or in tandem with the male. They descend as much as a foot under water to oviposit in aquatic vegetation.

Conservation:
Populations are widespread, abundant, and secure.
Status: Unprotected nongame species
Global Rank: G5
State Rank: S?

References:
Corbet, P. S. 1999. Dragonflies: Behavior and Ecology of Odonata. Cornell University Press, Ithaca, New York, USA, 829pp.

Logan, E. R. 1967. The Odonata of Idaho. Unpublished M. S. thesis. University of Idaho, Moscow, Idaho, USA, 105 pp.

Needham, J. G. and M. J. Westfall. 1955. Dragonflies of North America. University of California Press, Berkely, California, USA, 615 pp.

Paulson, D. R. 1999. Dragonflies of Washington. Seattle Audubon Society, Seattle, Washington, USA, 32 pp.

Walker, E. M. and P. S. Corbet. 1975. The Odonata of Canada and Alaska, Vol. III. University of Toronto Press, Toronto, Ontario, Canada, 307 pp.


Written by Mark Lung and Stefan Sommer, 2001
Photos by , 2001
Design by Ean Harker, 2001.