Everglades - Past

1
Everglades - Past

• A century ago, interconnected rivers, lakes, and
  wetlands spread across much of S. FL

2

• Beginning near Orlando, it extended south through
  the Kissimmee River to Lake Okeechobee,
• water seeped into an expanse of marshland
  reaching all the way to the tip of Florida, into
  Florida Bay,

3
Then Now
4
(No Transcript)
5

• eventually spilled over the Florida Keys onto the
  coral reef tract.
• People (1800s) reported hundreds of thousands of
  wading birds
• ibis, egrets, storks, and spoonbills
• Florida panthers, roamed the marshes.
• Alligators lived in the inland marshes,
  crocodiles along the coast.

6
(No Transcript)
7
(No Transcript)
8
Everglades - Present

• Everglades ecosystem is the most endangered
  ecosystem in the country.
• 1/2 have been drained and lost to urban and
  agricultural development.
• Remaining marshes are criss-crossed with 1,400
  miles of canals.
• Natural water flow patterns have been altered and
  regulated.

9

• Water flowing from farms and urban areas is often
  polluted with fertilizers pesticides
• Wading birds - decreased by 90 to 95
• More than a dozen species endangered among the
  Florida panther, American crocodile, wood stork,
  and snail kite.

10
LESS WATER ...

• Marsh now comprises about 2,300 sq. mi. 3/5 is
  impounded in the Water Conservation Areas.
• 2/3 now subsists on the rain that falls on 1/3 of
  the original watershed.
• These changes have reduced the availability of
  water and altered the Everglades hydroperiod.

11

• Impounded pools that accumulated during the wet
  season are rapidly drawn down.
• Most habitat vanished as a result of these
  massive changes
• Less water is available for the remaining
  wildlife.

12

• Much ecologically specialized wildlife has died
  or been forced out of the region.
• The alligator population has dropped from 50,000
  to 10,000.

13

• Snail kites (500 are left), and
• Wood storks are now seen in Central Florida
  because their habitat is gone.

14
EXOTIC PLANTS

• Brazilian pepper is a major problem.
• Far worse is the melaleuca tree
• It grows so densely that no other vegetation can
  compete, and wildlife can find little food.

15
ALTERED WATER CHEMISTRY

• Everglades is a highly oligotrophic system.
• Its native communities are in balance with the
  very low nutrient supplies provided by unpolluted
  rainfall.
• The rate of plant growth is probably limited by
  phosphorus

16

• Nutrients such as N and P due to human activities
  result in cultural eutrophication (fig. 14-23)
• 1. Mats of algae and microorganisms disappear
• 2. Blue-green algae appear in their place.

17

• 3. Dense monocultures of cattails force out
  native plant and take over marsh, wet prairie,
  and slough
• 4. Rapidly closing off open places where birds
  once fed.

18

• Because of the plants' rapid growth rate,
  detritus forms an anaerobic ooze under the
  cattails.
• Dissolved oxygen in the water is nearly zero.
• Other than air-breathing gambusia, no fish can
  survive in the water.

19

• When the Everglades Agricultural Area was
  drained, oxygen entered the soil, and
  microorganisms then completed the process of
  consuming it.
• The soil continues to oxidize, turning to a fine
  dust.
• In 60 years the soil surface of the EAA has
  dropped about five feet.

20

• The microbes also excrete phosphorus-which
  eventually enters the Everglades.
• Individuals who dispute the nature, extent, and
  significance of Everglades degradation appear to
  be employed, directly or indirectly, by
  agribusiness, the major pollution source.

21
Saving Our Future

• The Everglades restoration effort is the
  largest-scale project ever attempted
• Plans are underway to restore the water flow
  throughout in a way that mimics the natural flow.

22

• Clean up the polluted waters of the Everglades.
• Buy privately owned lands -- through federal and
  state acquisition programs -- before they are
  lost to development.