Subarctic Darner - Aeshna subarctica
The Subarctic Darner is circumboreal in its distribution, but is a fairly uncommonly occurring member of the family Aeshnidae found in isolated mountainous regions of Montana and is a species of concern. Darners are among the largest and fastest-flying North American dragonflies. Preferred breeding habitat of the Subarctic Darner is in swamps, fens, and bog ponds with a clear vegetative edge of abundant sphagnum and other mosses (Dunkle 2000, Paulson 2009). Similar to the Sedge Darner with black face line present, but lateral thoracic stripes are bent forward and have 2 narrow yellow spots present between the stripes.
Appearance is similar to the Sedge Darner with black face line present, but lateral thoracic stripes are bent forward and have 2 narrow yellow spots present between the stripes.
The Subarctic Darner is circumboreal in it's distribution, occurring throughout central and northern Europe, Eurasia and Japan (Dunkle 2000, Paulson 2009). In Montana, this species is currently known only from Mud Lake near Skalkaho Pass, Granite Co., though it probably occurs in other boreal areas of western Montana (Miller and Gustafson 1996).
Summary of Observations Submitted for Montana
Number of Observations:
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(Observations spanning multiple months or years are excluded from time charts)
The Subartic Darner breeds in swamps, fens, and bog ponds with a clear vegetative edge of abundant sphagnum and other mosses (Dunkle 2000, Paulson 2009).
Ecological Systems Associated with this Species
- Details on Creation and Suggested Uses and Limitations
How Associations Were Made
We associated the use and habitat quality (high, medium, or low) of each of the 82 ecological systems mapped in Montana for
vertebrate animal species that regularly breed, overwinter, or migrate through the state by:
- Using personal observations and reviewing literature that summarize the breeding, overwintering, or migratory habitat requirements of each species (Dobkin 1992, Hart et al. 1998, Hutto and Young 1999, Maxell 2000, Foresman 2001, Adams 2003, and Werner et al. 2004);
- Evaluating structural characteristics and distribution of each ecological system relative to the species’ range and habitat requirements;
- Examining the observation records for each species in the state-wide point database associated with each ecological system;
- Calculating the percentage of observations associated with each ecological system relative to the percent of Montana covered by each ecological system to get a measure of “observations versus availability of habitat”.
Species that breed in Montana were only evaluated for breeding habitat use, species that only overwinter in Montana were only evaluated for overwintering habitat use, and species that only migrate through Montana were only evaluated for migratory habitat use.
In general, species were associated as using an ecological system if structural characteristics of used habitat documented in the literature were present in the ecological system or large numbers of point observations were associated with the ecological system.
However, species were not associated with an ecological system if there was no support in the literature for use of structural characteristics in an ecological system, even if
point observations were associated with that system.
High, medium, and low habitat quality was assigned based on the degree to which the structural characteristics of an ecological system matched the preferred structural habitat characteristics for each species in the literature.
The percentage of observations associated with each ecological system relative to the percent of Montana covered by each ecological system was also used to guide assignments of habitat quality.
If you have any questions or comments on species associations with ecological systems, please contact Bryce Maxell at email@example.com
or (406) 444-3655.
Suggested Uses and Limitations
Species associations with ecological systems should be used to generate potential lists of species that may occupy broader landscapes for the purposes of landscape-level planning.
These potential lists of species should not be used in place of documented occurrences of species (this information can be requested at: http://mtnhp.org/requests/default.asp
) or systematic surveys for species and evaluations of habitat at a local site level by trained biologists.
Users of this information should be aware that the land cover data used to generate species associations is based on imagery from the late 1990s and early 2000s and was only intended to be used at broader landscape scales.
Land cover mapping accuracy is particularly problematic when the systems occur as small patches or where the land cover types have been altered over the past decade.
Thus, particular caution should be used when using the associations in assessments of smaller areas (e.g., evaluations of public land survey sections).
Finally, although a species may be associated with a particular ecological system within its known geographic range, portions of that ecological system may occur outside of the species’ known geographic range.
- Adams, R.A. 2003. Bats of the Rocky Mountain West; natural history, ecology, and conservation. Boulder, CO: University Press of Colorado. 289 p.
- Dobkin, D. S. 1992. Neotropical migrant land birds in the Northern Rockies and Great Plains. USDA Forest Service, Northern Region. Publication No. R1-93-34. Missoula, MT.
- Foresman, K.R. 2001. The wild mammals of Montana. Special Publication No. 12. Lawrence, KS: The American Society of Mammalogists. 278 p.
- Hart, M.M., W.A. Williams, P.C. Thornton, K.P. McLaughlin, C.M. Tobalske, B.A. Maxell, D.P. Hendricks, C.R. Peterson, and R.L. Redmond. 1998. Montana atlas of terrestrial vertebrates. Montana Cooperative Wildlife Research Unit, University of Montana, Missoula, MT. 1302 p.
- Hutto, R.L. and J.S. Young. 1999. Habitat relationships of landbirds in the Northern Region, USDA Forest Service, Rocky Mountain Research Station RMRS-GTR-32. 72 p.
- Maxell, B.A. 2000. Management of Montana’s amphibians: a review of factors that may present a risk to population viability and accounts on the identification, distribution, taxonomy, habitat use, natural history, and the status and conservation of individual species. Report to U.S. Forest Service Region 1. Missoula, MT: Wildlife Biology Program, University of Montana. 161 p.
- Werner, J.K., B.A. Maxell, P. Hendricks, and D. Flath. 2004. Amphibians and reptiles of Montana. Missoula, MT: Mountain Press Publishing Company. 262 p.
Larvae 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. The adult dragonfly will eat almost any soft-bodied flying insect including mosquitoes, flies, small moths, mayflies, and flying ants or termites.
Male Subarctic Darners are only territorial at low population densities and do not patrol regular routes. They fly over open water and floating sphagnum mats, hover for a period then continue on to another floating mat. Females oviposit in mosses and sedges at the waterline at the edge of open water (Dunkle 2000, Paulson 2009).
- Literature Cited AboveLegend: View Online Publication
- Miller, K.B. and D.L. Gustafson. 1996. Distribution records of the Odonata of Montana. Bulletin of American Odonatology 3(4):75-88.
- Additional ReferencesLegend: View Online Publication
Do you know of a citation we're missing?
- Dunkle, S.W. 2000. Dragonflies through binoculars: A field guide to dragonflies of North America. New York, NY. Oxford University Press. 266 pp.
- Kohler, Nathan S. Excel spreadsheets of Odonate observations/collections in Montana.
- Paulson, D.R. 2009. Dragonflies and Damselflies of the West. Princeton University Press, Princeton. 535 pp.
- Paulson, D.R. and S.W. Dunkle. 2009. A checklist of North American Odonata including English name, etymology, type locality, and distribution. Originally published as Occasional Paper No. 56. Slater Museum of Natural History, University of Puget Sound, June 1999; completely revised March 2009.