Florida's
Everglades contains both temperate and tropical plant communities,
including sawgrass prairies, mangrove and cypress swamps, pinelands, and
hardwood hammocks, as well as marine and estuarine environments.
National
Park Service Map
Everglades
National Park is the largest remaining sub-tropical wilderness in the
continental United States and has extensive fresh and saltwater areas,
open Everglades prairies, and mangrove forests.
The
boundaries of Everglades National Park protect only the southern
one-fifth of the historic Everglades ecosystem. In its entirety, this
massive watershed boasts a multitude of habitats and wildlife thriving
in a unique assemblage amidst the subtropics.
The
area boasts rare and endangered species, such as the American crocodile,
Florida panther, and West Indian manatee.
Abundant wildlife
includes rare and colorful birds, and this is the only place in the
world where alligators and crocodiles exist side by side. The park is
1,506,539 acres (606,688 hectares) in size.
Park Rangers talk
about how the Everglades work
Climate
The Everglades is mild and pleasant
from December through April, though rare cold fronts may create near freezing
conditions. Average temperatures in winter - High 77°F (25°C); Low 53°F (12°C).
Summers are hot and humid, with temperatures around 90°F (32°C) and humidity
over 90%. Afternoon thunderstorms are common and mosquitoes are abundant. The
Atlantic Hurricane Season is June-November. Tropical storms or hurricanes may
affect the area. Average Rainfall: 60 inches (152 cm) per year. The rainy season
is June through October (mosquito season coincides with the rainy season).
Once,
water flowed freely from Lake Okeechobee to Florida Bay, a "river
of grass" 120 miles long and 50 miles wide, but less than a foot
deep.
In this flat landscape, even a few inches of elevation meant the
difference between wet marsh and dry ground. Today, the Everglades is an
ecosystem in danger. Canals and levees capture and divert its water for
human needs, including drinking water, irrigation, and flood control.
Often, too much water is withheld from the Everglades during the wet
season, or too much is diverted into it during the winter drought,
disrupting the natural cycles of feeding and nesting which depend on
these patterns. Sometimes the water is contaminated by pollutants. Faced
with loss of habitat, disruption of water flow, and the invasion of
non-native species, many animals have declined dramatically in number.
Some have virtually disappeared.
NASA/GSFC/JPL,
MISR Team Satellite: Terra Sensor: MISR
These
MISR nadir-camera images of southern Florida were acquired on October 18,
2000 (Terra orbit 4446). The view on the left includes Daytona Beach near
the top and the Florida Keys at the bottom. Orlando appears as a grayish
patch near the top of the image, just to the east of the greenish Lake
Apopka, Florida's fourth largest and most polluted lake. On the coast is
Cape Canaveral, home of the Kennedy Space Center. The large body of water
in the middle of the land area is Lake Okeechobee. On the western (Gulf of
Mexico) coast, Charlotte Harbor and Fort Myers are visible. Along the
eastern (Atlantic) coast, partially obscured by clouds, are Palm Beach,
Fort Lauderdale, and Miami. Further to the east, the shallow waters and
reefs of the Little Bahama and Great Bahama Banks appear in striking blue
and green colors. The two righthand images show the Florida Everglades and
the Keys in more detail. Like the lefthand view, the top image is a
natural color composite of blue, green, and red band imagery. On the
bottom is a false color composite comprised of green, red, and
near-infrared data. Near-infrared light is invisible to the human eye. The
high reflectance of plants in this part of the electromagnetic spectrum,
displayed here in shades of red, is the basis of many satellite-based
techniques for detecting and characterizing land surface vegetation.
Few
wetlands demonstrate dilemmas of development more starkly than Florida's
Everglades. Since 1920, drainage to create farmland or housing has dried
out half of the Everglades National Park, and left the rest heavily
polluted.
The
Everglades' sawgrass fields, dry pinelands, "islands" of trees,
and mangrove forests once supported over 600 kinds of animals and 900 of
plants. In the past 50 years, pollution or water-flow disruption and
complete drainage in some areas have disturbed or destroyed many habitats.
Wild populations, especially of birds, have plummeted; the number of
wading birds that nest in the national park has dropped by more than 90
percent.
Development In
The Everglades
Water in south Florida once
flowed freely from the Kissimmee River to Lake Okeechobee and southward over
low-lying lands to the estuaries of Biscayne Bay, the Ten Thousand Islands,
and Florida Bay. This shallow, slow-moving sheet of water covered almost
11,000 square miles, creating a mosaic of ponds, sloughs, sawgrass marshes,
hardwood hammock, and forested uplands. For thousands of years this intricate
system evolved into a finely balanced ecosystem that formed the biological
infrastructure for the southern half of the state.
Early colonial settlers and
land developers viewed the Everglades as a worthless swamp in need of
reclamation. The dream of draining the swampland took hold in the first half
of the 1800s. By the 1880s developers started digging drainage canals, which
took place without an understanding of the dynamics of the ecosystem and were
generally inadequate for the task. They caused localized silting problems, but
overall the ecosystem was resilient enough to sustain itself.
The notion of draining the vast
wetland persisted. Expanded dredging efforts between 1905 and 1910 transformed
large tracts from wetland to agricultural land. This abundance of
"new" land stimulated the first of several south Florida land booms.
Railroads constructed by entrepreneurs like Henry B. Plant and Henry M.
Flagler made the region more accessible and attractive to tourists. By the
1920s visitors and new residents flocked to blossoming towns like Fort
Lauderdale, Miami, and Fort Myers. As they arrived, developers cut more canals
and built new roads. To ensure good ocean views, they removed mangroves from
the shorelines and replaced them with palm trees. Little by little canals,
roads, and buildings displaced native habitats.
The year 1948 marked an even
greater change when Congress authorized the Central and South Florida Project.
This involved the construction of an elaborate system of roads, canals,
levees, and water-control structures stretching throughout South Florida.
Constructed by the Army Corps of Engineers, and sponsored by the Central and
Southern Flood Control District (later redesignated the South Florida Water
Management District), the project purposes were to provide water and flood
protection for urban and agricultural lands, a water supply for Everglades
National Park, the preservation of fish and wildlife habitat, facilitate
navigation and recreation, and the prevention of salt water intrusion. While
the project still provides many of the intended benefits, the alteration of
regional wetland areas, estuaries, and bays — combined with increasing
population pressures and changing land uses — has significantly degraded the
natural system.
Today 50% of south Florida’s
original wetland areas no longer exist. The numbers of wading birds, such as
egrets, herons, and ibises, have been reduced by 90%. Entire populations of
animals, including the manatee, the Cape Sable seaside sparrow, the Miami
blackheaded snake, the wood stork, and the Florida panther, are at risk of
disappearing. Exotic pest plants such as melaleuca, Brazilian pepper, and
Australian pine have invaded natural areas, choking out native plants and
altering habitats. Massive die-offs of seagrass beds in Florida Bay have been
followed by the extensive losses of wading birds, fish, shrimp, sponges, and
mangroves. These grim indicators warn of a system under assault and in
jeopardy of collapse.
Native Peoples
Recent surveys in the Everglades
and within the Big Cypress Swamp indicate the presence of at least several
hundred archeological sites within the interior of south Florida. Some of these
sites proved to be substantial, and suggest more than just marginal or
short-term use. Based on current data, it also appears that the sawgrass plains
region south of Lake Okeechobee, now the Everglades Agricultural Area, was a
transitional area used for canoe travel and small encampments by many tribes.
The exceptions are earthwork complexes, some of which are known to be located on
the western edge of the Everglades. These sites show a strong affiliation with
the Belle Glade Area on the shores of Lake Okeechobee. Pottery remains found in
portions of the southwest section of the Everglades Agricultural Area indicate
influence from regions as far away as Ten Thousand Islands/Florida Bay on the
southernmost end of the state. The settlement of South Florida, which has
occurred since 10,000 b.c., has been chronologically categorized up until a.d.
1930.
Paleo-Indian Period (10,000
b.c. to 8000 b.c.) — The Paleo-Indian likely lived with mammoths, bison,
and other types of megafauna in arid climate conditions. With the extinction of
these animals, the Paleo-Indian adapted to the changing climate and emerging
wetlands and began to establish patterns of subsistence (deer and rabbit
hunting, as well as marine life gathering).
Archaic Period (8000 b.c. to
750 b.c.) — During the Post Glacial period, the sea level rose and
diminished Florida’s land base, and the climate began to change. By 5000 years
ago, cypress swamps and hardwood forests characteristic of subtropical terrain
began to develop. The people of this period increasingly relied on shellfish and
other coastal resources, as well as expanded hunting, fishing, and plant
gathering. From the Early Archaic Period to the Late Archaic Period, advances
were made in the shaping and use of tools and pottery. Remnants of the tools and
pottery are valuable in dating these sites.
The Glades Period (ca. 750
b.c. to a.d. 1500) — The Glades I, II, and III periods are dated and
characterized by pottery types. During the Glades II and III periods, evidences
of a thriving trade network is evidenced by a variety of exotic resources, such
as lithic tools and ornaments.
Historic Contact Period (ca.
a.d. 1500 to a.d. 1750) — This period includes the arrival of the
Europeans and their encountering of a thriving population of at least five
separate tribes: the Tequesta in southeast Florida, the Calusa in the southwest,
and the Jeaga and Ais along the east coast north of the Tequesta, and the
Mayaimi near Lake Okeechobee. At the time of Spanish contact the Calusa
maintained political dominance over these groups. It has been estimated that
there were approximately 20,000 Indians in south Florida when the Spanish
arrived. By 1763 when the English gained control of Florida, that population had
been reduced to several hundred, which were reported to have migrated to Cuba
with the Spanish (Romans 1962).
Historic Period (ca. a.d.
1750 to a.d. 1930) — There is little information on any pre-19th century
activities in the area south of Lake Ockeechobee. With the demise of indigenous
people in south Florida, and white settlement occurring to the north, increasing
migrations of Creek peoples moved southward for hunting and settling. The Creeks
and proto-Seminoles were in the area as early as the eighteenth century. During
the Seminole Wars (1817–18, 1835–42, 1855–58) independent bands of Florida
Indians established themselves in the Everglades to avoid removal from Florida
Southern
Florida’s River of Grass
from
NASA Visible Earth
Image
courtesy NASA/GSFC/LaRC/JPL, MISR Team. Satellite: Terra Sensor: MISR
Image
Florida’s
Everglades is a region of broad, slow-moving sheets of water flowing southward
over low-lying areas from Lake Okeechobee to the Gulf of Mexico. In places this
remarkable ‘river of grass’ is 80 kilometers wide. This image above is from
the Multi-angle Imaging SpectroRadiometer show the Everglades region on January
16, 2002. Each image covers an area measuring 191 kilometers x 205 kilometers.
This
image above is a natural color view acquired by MISR’s nadir camera. A portion
of Lake Okeechobee is visible at the top, to the right of image center. South of
the lake, whose name derives from the Seminole word for ‘big water’, an
extensive region of farmland known as the Everglades Agricultural Area is
recognizable by its many clustered squares. Over half of the sugar produced in
United States is grown here. Urban areas along the east coast and in the
northern part of the image extend to the boundaries of Big Cypress Swamp,
situated north of Everglades National Park.
This image combines red-band data
from the 46-degree backward, nadir and 46-degree forward-viewing camera angles
to create a red, green, blue false-color composite. One of the interesting uses
of the composite image is for detecting surface water. Wet surfaces appear blue
in this rendition because sun glitter produces a greater signal at the forward
camera’s view angle. Wetlands visible in these images include a series of
shallow impoundments called Water Conservation Areas which were built to speed
water flow through the Everglades in times of drought. In parts of the
Everglades, these levees and extensive systems such as the Miami and Tamiami
Canals have altered the natural cycles of water flow. For example, the water
volume of the Shark River Slough, a natural wetland which feeds Everglades
National Park, is influenced by the Tamiami Canal. The unique and intrinsic
value of the Everglades is now widely recognized, and efforts to restore the
natural water cycles are underway.
Credit: The National Park
Service, USGS,NASA
Data
compiled from The British Antarctic Study, NASA, Environment Canada,
UNEP, EPA and other sources as stated and credited Researched
by Charles Welch-Updated dailyThis Website is a project of the The
Ozone Hole Inc. a 501(c)(3) Nonprofit Organization
