Sympetrum occidentale
(Western Meadowhawk)


Order: Odonata
Suborder: Anisoptera
Order Description:
Dragonflies
Family: Libellulidae
Family Description: Meadowhawk

Description:
   Naiad- This is a small naiad with a length of 5/8 inch (16 mm). It is mottled green and brown in color. The abdomen has several small hooks along the top, and the last two abdominal segments have a small, single, rear-facing spine on each side.
   Adult- This is a small dragonfly with a length of 1 1/4 to 1 5/8 inches (31 to 40 mm). The key distinguishing feature is a cloudy, orange-brown band that covers the inner half of each wing. The band may appear darker towards the outside. Males have a yellowish thorax, marked with wavy black lines on each side, and a red to reddish brown abdomen, marked with black along the bottom edge of each side. Females are olive to golden brown and marked similarly.

Range:
This species is found from British Columbia east to Alberta, extending south into the U.S. to California east to Utah. It is common throughout Idaho.

Habitat:
This dragonfly can be found in most types of ponds and lakes.

Adult Flight Season:
Mid-June to mid-October

Diet:
   Naiad- Naiads feed on a wide variety of aquatic insects, such as mosquito larvae, other aquatic fly larvae, mayfly larvae, and freshwater shrimp. They will also eat very small fish and tadpoles.
   Adult- The dragonfly will eat almost any soft-bodied flying insect including mosquitoes, flies, small moths, mayflies, and flying ants or termites.

Ecology:
The naiads live in submerged vegetation. They do not actively pursue prey but wait for it to pass by, a strategy which affords them protection from other predators. Naiads emerge as adults at night. Adults generally fly from mid-June to mid-October, resulting in a long flight season in Idaho which lasts almost four months. The adults of this species hunt flying insects from perches on rocks or bare branches. The Latin name for this genus, Sympetrum, means "with rock" and refers to their habit of basking on rocks to absorb heat early in the day. This species has been observed being captured and eaten by larger species of dragonflies, especially the Olive Clubtail (Stylurus olivaceous) at Massacre Rocks State Park, near American Falls, Idaho.

Reproduction:
The female flies with the male still attached after mating (a position called "in tandem") and lays her eggs in lakes and ponds by dipping the tip her abdomen on the surface of the water.

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 Dennis Paulson, 2001
Design by Ean Harker, 2001.

HTML by Marty Peck, 2001.