Aeshna canadensis Walker, 1908
Canada Darner
NatureServe Global Rank: G5
Virginia State Rank: S1
VA DGIF Tier: IV
Federal Legal Status: None
Virginia Legal Status: None
Description: The Canada Darner is a "mosaic" darner with a complex pattern of blue markings on a dark abdomen. The thorax has two blue vertical stripes on the side, the front stripe being sharply indented and with a rearward extension ("flag") along the top. There is a small yellow spot between the thoracic stripes. The size is 64-73 mm (2.5-2.9 inches.)
Similar species: In Virginia, the Shadow Darner (A. umbrosa) is far more common and widespread. It can be readily separated from the Canada Darner by its straight and narrow thoracic stripes, and by the much smaller mosaic patterns of the abdomen. The Canada Darner is very similar to the Green-striped Darner (A. verticalis). It can be distinguished in hand by the pattern of the thoracic stripes with a yellow spot between, and by the lateral markings on the second abdominal segment. The blue color of the thoracic stripes, as opposed to green in the Green-striped Darner is often helpful, but there can be some color variation (Paulson, 2011). See illustrations on p. 70 of Nikula (2003). The Black-tipped Darner (A. tuberculifera) is also very similar, but it lacks blue markings on the last abdominal segment and the thoracic stripes are straight.
North American Range: The Canada Darner can be found all across the northern United States and southern Canada. In Virginia, this species has only been recorded in Highland County, and represents the southernmost breeding location in the east (Roble et al, 2009).
VA Observations by Locality: Highland
Flight season and broods: The flight season in Virginia for the Canada Darner ranges from 12 June (based on an exuvia) through 3 October.
Aquatic Habitat: The Canada Darner is found in marshes, lakes, and beaver ponds, with emergent vegetation. The only known sites in Virginia occur at high elevation beaver ponds.
Behavior and Ecology: Canada Darner adults hunt by patrolling shorelines or sunny clearings. They hang vertically in woody vegetation while at rest. They may be found in mixed species swarms, especially late in the day, with other species of darners and emeralds.
Population trend and potential threats: The Canada Darner is a common species farther north, but rare boreal habitat in its Virginia location should be protected.
Management practices: Maintenance of rare boreal habitat in Virginia is essential.
References: Nikula, B., J. Loose, and M. Burne. 2003. A Field Guide to the Dragonflies and Damselflies of Massachusetts. Massachusetts Division of Fisheries and Wildlife, Natural Heritage & Endangered Species Program. Westborough, Massachusetts. 197 pp.
Paulson, Dennis. 2011. Dragonflies and Damselflies of the East. Princeton University Press, Princeton, NJ. 530 pp.
Roble, Steven M. 2011. Dragonflies of Virginia- Flight dates. Unpub.
Roble, S. M., Carle, F. L., and O. S. Flint. 2009. Dragonflies and Damselflies (Odonata) of the Laurel Fork Recreation Area, George Washington National Forest, Highland County, Virginia: Possible evidence for Climate Change. Pp 365-399, in S. M. Roble and J.C. Mitchell (eds.). 2009. A lifetime of contributions to Myriapodology and the Natural History of Virginia. Virginia Museum of Natural History Special Publication No. 16, Martinsville, Virginia.