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The U.S. Fish and Wildlife Service is designating critical habitat for the Hine’s emerald
dragonfly (Somatochlora hineana) in Illinois, Michigan, and Wisconsin. The Hine’s
emerald dragonfly is listed as endangered under the Endangered Species Act of 1973, as
amended.
Background
Natural History
Adult Hine’s emerald dragonflies have bright emerald-green eyes and metallic green
bodies with yellow stripes on the sides. The body is about 2½ inches long with a
wingspan of 3½ inches. Hine’s emerald dragonflies use a variety of habitats - most are
wetland systems. The dragonfly breeds in marshes and sedge meadows that are underlain
by dolomite bedrock (magnesia-rich sedimentary rock resembling limestone) and fed by
calcareous (calcium carbonate, calcium or limestone) groundwater seeps. Eggs are laid in
shallow water and immature dragonflies, called larvae, hatch the following spring. Larvae
are aquatic, living in rivulets and seepage areas within wetland systems for 3 to 5 years,
eating smaller insects and shedding their skin many times. Larvae then crawl out of the
water and shed their skin a final time, emerging as flying adults. Adults can live at least
14 days and may live 4 to 6 weeks. During that time they use wetlands as well as a
mixture of adjacent uplands.
Threats
Actions that threaten the continued existence of the Hine’s emerald dragonfly are those
that destroy, degrade, alter, and fragment habitat.
Direct loss of habitat from urban development, new landfills, and new pipelines decreases
the area of suitable habitat and can fragment existing dragonfly populations. Quarrying
can also destroy Hine’s habitat because this species is closely associated with surface
dolomite deposits which have commercial value.
Contamination from landfills, transportation, agriculture, and habitat-altering chemical
applications may degrade habitat. The species’ long aquatic larval stage (3 to 5 years)
makes it vulnerable to ground and surface water contamination.
Natural succession and encroachment of invasive species negatively impacts the species
habitat. Natural succession may result from releases of nutrients and road salt into
surface waters or connected groundwater, and invasive species may be introduced
through human activities in the habitat.
Increased deposition of sediment harms areas within wetlands where Hine’s emerald
dragonflies breed. Activities that may cause excessive sedimentation include livestock
grazing, road construction, stream channel alteration, timber harvest, all terrain vehicle
use, horseback riding, feral pig grazing, rail lines and other disturbances to the watershed
and floodplain.
Alteration of water quantity and quality in wetland systems can impact Hine’s breeding
habitat. Activities that change water quality and quantity include groundwater extraction;
alteration of surface and subsurface areas within groundwater recharge areas; and release
of chemicals, biological pollutants, or heated effluents into the surface water or
groundwater recharge area.
Hine’s emerald dragonfly breeding habitat can also be harmed by alteration of channels
in wetland systems. Channels within wetlands could be harmed or altered by all terrain
vehicle use, horseback riding, feral pigs, channelization, beaver dams, impoundment,
road and bridge construction, mining, and loss of emergent vegetation. These activities
may lead to changes in water flow velocity, temperature, and quantity.
Activities that fragment habitat are harmful because they affect the ability of adults to
forage or disperse to new areas. This, in turn, may result in reduced fitness and genetic
exchange within populations as well as direct mortality of individuals. Activities that
fragment habitat include road construction, destruction or fill of wetlands, and high-speed
railroad and vehicular traffic.
Critical Habitat
Critical habitat is a tool within the Endangered Species Act that identifies areas that are
important to the conservation and recovery of a listed species. Within areas that are
designated as critical habitat, federal agencies are required to do a special review of
activities that they intend to carry out, fund, or permit. Their activities cannot destroy or
adversely modify the important components of critical habitat. However, a critical habitat
designation does not affect actions that do not involve a federal agency. For example, the
designation of critical habitat does not affect a landowner undertaking a project on
private land that does not involve federal funding or require a federal permit or
authorization.
Designation of critical habitat can help focus conservation activities for a listed species
by identifying areas that contain the physical and biological features that are essential for
the conservation of that species. Also, designation of critical habitat alerts the public as
well as land-managing agencies to the importance of these areas, but the Endangered
Species Act only imposes additional restrictions on the actions of federal agencies.
When deciding what areas to designate as critical habitat, the Service looks at the
physical and biological features that are necessary for the species to survive. These
required features are called “primary constituent elements.” Primary constituent
elements include space for individual and population growth, and for normal behavior;
space for food, water, air, light, minerals, or other nutritional or physiological
requirements; cover or shelter; sites for breeding, reproduction, or rearing of offspring;
and habitat that is protected from disturbance or is representative of the historic
geographical and ecological distributions of a species.
The Critical Habitat Designation for Hine’s Emerald Dragonfly
The essential primary constituent elements for Hine’s emerald dragonfly egg laying and
larval development are found in wetlands with organic soils overlying dolomite bedrock. Those wetlands have shallow calcareous water from intermittent seeps and springs,
emergent herbaceous and woody vegetation, crayfish burrows (that provide refuges for
larva), and a sufficient prey base of aquatic insects and other invertebrates.
The essential primary constituent elements for Hine’s emerald dragonfly adults are found
in natural plant communities in or near the breeding/larval wetlands that have a sufficient
prey base of small insect species. Those natural plant communities include fen, marsh,
sedge meadow, dolomite prairie, the fringe (up to 328 feet) of shrubby and forested areas
bordering those wetlands and open corridors (non-forested) that adults use for movement
and dispersal.
The Service is designating critical habitat within 22 units encompassing approximately
13,221 acres in eight counties in Illinois, Michigan, and Wisconsin. Within the critical
habitat units, only the areas that contain the primary constituent elements of Hine’s
emerald dragonfly habitat are designated as critical habitat. These units occur in the
following states and counties:
Illinois: Seven units encompassing 2,995 acres in Cook, DuPage, and Will
counties.
Michigan: Four units encompassing 1,385 acres in Alpena, Mackinac, and
Presque Isle counties.
Wisconsin: Eleven units consisting of 8,841 acres in Door and Ozaukee counties.
Improved mapping technology enabled the Service to eliminate homes, roads, airport
runways, and other human-made structures as well as lawns, agricultural fields, and
closed-canopy forests from the critical habitat units. Mapping is still not precise enough
to exclude all such areas so some of these features may remain within the designated
areas. However, even if such areas fall within the boundaries of designated critical
habitat, they are still not considered actual critical habitat under the provisions of the
Endangered Species Act.
Exclusions
The Service excluded 28 units from the final critical habitat designation. Fourteen units
in Missouri and two units in Michigan were excluded because public land managers are
currently implementing conservation actions for the Hine’s emerald dragonfly under
existing land management plans. Because they are implementing those conservation
efforts, benefits of designating critical habitat for the Hine’s emerald dragonfly on these
public lands are small in comparison to the benefits of excluding those areas from the
final designation. Exclusions will continue to enhance the partnership efforts with the
Forest Service and the Missouri Department of Conservation that are focused on
conservation of the species on those lands.
The 12 remaining units in Missouri are on private lands; the Service excluded private
lands in Missouri because the Missouri Department of Conservation has implemented
successful conservation efforts on some of those lands and has plans for implementing
further conservation actions on remaining lands. The existing partnerships between the
Missouri Department of Conservation and property owners could dissolve current and
future conservation efforts that could be negatively impacted if critical habitat were
designated. Maintaining those working partnerships is important to recovering the Hine’s
emerald dragonfly.
Economic Analysis
When specifying an area as critical habitat, the ESA requires the Service to consider
economic and other relevant impacts of the designation. Estimated costs associated with
conservation activities for the endangered Hine’s emerald dragonfly (Somatochlora
hineana) in areas proposed as critical habitat for the species may range from $16.8 to
$47.9 million over the next 20 years, according to an economic analysis released by the
Service. Most of the costs linked to conservation of the Hine’s emerald dragonfly are
associated with the residential and commercial development industry.
Additional Information
The U.S. Fish and Wildlife Service posts information about the Hine’s emerald dragonfly
at http://www.fws.gov/midwest/Endangered. You may also contact the Chicago, Illinois
Ecological Services Field Office at 1250 S. Grove, Suite 103, Barrington, Illinois 60010,
(telephone (847) 381-2253; facsimile (847) 381-2285).
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