EarthKeepers will design, coordinate and
implement customized consulting, guidance, retreats and workshops
on environmental education, personal and spiritual growth, lifestyle
management, and sustainable living practices. Please
contact us for details on specific needs
Mississippi Piedmont Rivers and Streams
Great Smokey Mountains National
Park, Eastern North America: Alabama, Georgia, Kentucky,
North Carolina, Tennessee, and Virginia Large River Headwaters
The watershed of these rivers and streams covers more than 200,000
square miles (525,000 square kilometers) -- about twice the size
of Wyoming. Critical/Endangered
·
Global 200 Snapshot
The Mississippi Piedmont Rivers and Streams ecoregion is the richest
freshwater system of its kind in the world. It is recognized as
having greater diversity of mussels, crayfish, salamanders, and
freshwater fish than anywhere else in the world, with a comparable
climate.
A Refuge from Ice
The diversity of habitats, age, favorable climate, and
geologic stability of the region, along with its escape from glaciation
during the last Ice Age, have promoted the evolution of a high
diversity of animals. When much of North America was covered in
ice, this region remained unglaciated and a refuge for many aquatic
species. Thus, species in this area had 375 million years during
which to evolve, as opposed to the 10,000 to 15,000 years of more
northern areas. The high ridges and low valleys of these mountain
ranges have also allowed for the complete isolation of many waterways
from one another, thus enabling evolution of species unique to
each of these isolated rivers and streams. One ancient species
is the hellbender, a huge salamander (reaching a length of over
23 inches, or 60 cm) whose closest relatives live in Japan and
China.
Special Features
The Mississippi Piedmont Rivers and Streams ecoregion is a network
of waterways originating in mountain ranges that include the Ozark,
Ouachita, Appalachian, and Cumberland. Because of the isolation
created by the ridges and valleys and the large number of rivers
and streams in this region, it is possible to find species that
live only in a very limited area or one body of water. The main
rivers of the ecoregion are the Tennessee, Cumberland, and Ohio.
These and other rivers and streams erode rock and soil as they
flow, eventually depositing mineral-rich and nourishing silt in
swamps, forests, and farmland.
Freshwater mussels have a parasitic life-stage (glochidia) in
which they attach themselves to fish, or sometimes amphibians.
These glochidia stay buried in the fish’s tissue for days or months
until the capsule they have created explodes and many young mussels
emerge to settle on the bottom of the lake or stream. Glochidia
attach to gills, fins, lips, barbels, or other portions of the
fish’s body. Some mussels need a certain species of fish in order
to reproduce, meaning that the mussel has evolved such that only
one host fish species will carry its glochidia. Thus, if these
fish species become extinct, the mussel species that depends on
it for dispersing its larvae will become extinct as well.
Wild Side The Nashville crayfish
is native to these waters, which are shared by fish such as firebelly
and duskytail darters, smoky madtoms, palezone shiners, sturgeon,
and paddlefish. Salamanders include the West Virginia spring,
imitator, shovelnose, and streamside. Any relatively intact stream
in this region supports more species of mussels than all of Australia
and Europe combined. These species live embedded in the bottom
of the stream, river, or lake, where they pump water through their
gills and filter out suspended bits of food. Some can be extremely
long-lived, including one species that can live for more than
120 years!
Cause for Concern
For decades, the rivers and streams of this ecoregion have
been used to transport goods, create electricity, and irrigate
agriculture. Such activities have required the building of dams
and the digging of canals, which have created problems for native
wildlife. The Tennessee River system, for example, has more than
50 major dams, and the impoundments behind them have restricted
the movements of many freshwater species. Pollution from cities
and farms also threaten aquatic species. Mussels in particular
are threatened by sedimentation because they are sedentary and
unable to escape from the particles that clog their gills. Introduced
species, such as the zebra mussel, compete with native species
for resources and habitat.
Looking Ahead
Several conservation and governmental organizations have recently
reintroduced lake sturgeon into the French Broad River. This stretch
of river is a relatively free-flowing portion of the upper Tennessee
River, in which several freshwater mussel and snail species are
also making a comeback. Protection and restoration efforts continue
on selected streams in high-priority areas (e.g., the Clinch River
biopreserve). Continued work, in cooperation with local landowners,
is needed to create "buffer strips" of native vegetation
along streams and to limit soil erosion.
All text by
World Wildlife Fund © 2001
Southeastern Coniferous
and Broadleaf Forests
Southeastern United States Temperate Coniferous Forests About
225,000 square miles (585,000 square kilometers) -- almost the
size of Texas Critical/Endangered
· Complex Conifer Communities·
Special Features· Did You Know?·
Wild Side· Cause for Concern· Looking Ahead Global
200 SnapshotThis ecoregion is one of the best examples of temperate
conifer forests in eastern North America, and it contains one
of the highest levels of plant diversity in the world. It is also
known as the richest in the world for spring wildflowers. This
Global 200 ecoregion is made up of these terrestrial ecoregions:
Southeastern mixed forests; Southeastern conifer forests Complex
Conifer CommunitiesThe Southeastern Conifer and Broadleaf Forests
are a great place to see the complex interactions of animals in
a forest community. If you come across the burrow of a gopher
tortoise in these forests, don't expect only a tortoise head to
come poking out. Mice, rabbits, raccoons, foxes, Virginia opossums,
rats, burrowing owls, skinks, eastern fence lizards, eastern spadefoot
toads, crayfish, frogs, insects, and even eastern diamondback
rattlers are all known to use these burrows for temporary or permanent
shelter. Similarly, if you're lucky enough to see a rare and endangered
red-cockaded woodpecker feeding in a tree, keep your eye out for
Carolina chickadees, pine warblers, and tufted titmice. These
birds know that when a red-cockaded woodpecker yanks the bark
off a tree, it exposes insects for other hungry mouths. These
are just a few examples of the many fascinating ways that organisms
in these coniferous communities interact with depend on one another.
Special Features
This ecoregion is the largest coniferous forest ecoregion east
of the Mississippi River, spanning the coastal plain of the southeastern
United States. When fires were common in these forests, the dominant
tree species were almost exclusively pine trees, which are adept
at "pioneering" a recently burned area. Tall stands
of long-leaf pines dominated in many areas with an understory
of wire grass and a rich diversity of herbaceous plants. Ever
since people have suppressed fires, though, hardwood trees have
had a chance to take root and grow beside or even out-compete
the sun-loving pines.
Male gopher tortoises joust with one another for mates and for
territory. Whoever gets flipped over on his back first is the
loser!
Wild Side You'll find 190 species
of trees in this ecoregion, with 27 found here and nowhere else.
Endangered red-cockaded woodpeckers build their nests in the soft,
fungus-infected hollows of old pine trees, now so rare that the
woodpeckers are in serious trouble. Apalachicola dusky salamanders
spend their days under streambank debris. Smooth and shiny lizards
called mole skinks keep alert for potential insect meals. Eastern
indigo snakes feed on small mammals, birds, frogs, and other snakes.
And in warm weather, gopher tortoises emerge from the burrows
each morning to forage on grass, leaves, and wild fruits.
Cause for Concern
Intensive logging has degraded and destroyed almost all
of the original native forest, endangering many species. Many
conifer stands are converting to hardwood species due to fire
suppression. And urban sprawl and development continue to threaten
remaining blocks of habitat. If action is not taken to protect
the few remaining blocks, this valuable ecoregion may not exist
for much longer.
Looking Ahead Check
back soon for more about the conservation of this
ecoregion.All
text by World Wildlife Fund © 2001