Everglades: Ecosystem, Transformation, and Conservation

Everglades National Park: A Watery Wilderness Under Pressure

Contrasting Everglades with Yellowstone

• Everglades National Park: Characterized as a 'watery wilderness,' it is enveloped by major cities and dense human activity. Its proximity to urban centers like Greater Miami, Fort Lauderdale, and Homestead, Florida, highlights significant human-wildlife interaction and habitat pressure.
• Yellowstone National Park: In stark contrast, Yellowstone is situated in a sparsely populated region with very few large cities nearby. Boise, the largest city, is over 150 miles away, leading to different conservation challenges.

The Unique Aquatic Environment: Florida Bay and Brackish Water

• Everglades' Dual Nature: The park encompasses both land and significant water areas, with Florida Bay to its south, leading into the Gulf of Mexico.
• Estuary Definition: An estuary is a marine environment where freshwater from rivers mixes with saltwater from the ocean. It is neither fully salty nor fully fresh.
• Brackish Water: This term describes the unique blend of fresh and salt water found in estuaries, crucial for the diverse ecosystems of the Everglades.

Endangered Species in the Everglades

The West Indian Manatee

• Description: A large, herbivorous marine mammal.
• Habitat Preference: Manatees thrive in shallow, warm, and protected waters, such as Florida Bay. They feed on seagrass.
• Florida Bay Characteristics: Protected by the Florida Keys to the south and the Florida Mainland to the north, resulting in calm waters with very few waves. The bay is exceptionally shallow; at low tide, much of it is traversable on foot.
• Personal Anecdote: An encounter in Key Largo where a manatee, with its distinctive spade-shaped tail, playfully 'slurped spaghetti' by stripping algae off boat lines, demonstrating its gentle nature.

The American Crocodile

• Rarity: American crocodiles are very rare and considered highly endangered.
• Behavior and Habitat: They are significantly shyer than alligators and prefer brackish water environments. Unlike alligators, crocodiles are not typically found in human-dominated areas like backyard pools or golf courses.
• Reproductive Differences: Crocodiles are a K-selected species, meaning they have much slower reproductive rates compared to the r-selected alligators, making their recovery more challenging.
• Distinguishing Features (Visual):
  • Alligators: Display a beautiful bronzy-black coloration.
  • Crocodiles: Tend to be more olive green in color, in addition to having different skull shapes and snout structures.

Alligators: A Conservation Success Story

• Historical Decline: American alligators were once hunted to near extinction in the American South, with only a few hundred individuals remaining.
• Recovery: Through protection efforts, and aided by their high reproductive rates, alligator populations have rebounded significantly and are now very common.

Wading Birds: Indicators of Ecosystem Health

• Diversity and Habitat: The Everglades supports a rich diversity of wading birds, which thrive in its shallow waters.
• Endangered Species: Storks are another endangered species found in South Florida.
• Audubon's Role in Monitoring: The Florida Audubon Society, with a network of volunteers, conducts systematic bird counts to estimate population sizes and changes over time, including seasonal and Christmas bird counts.
• Key Species Monitored:
  • White Ibis: Recognizable by its narrow, curved bill, resembling the ibises depicted in Egyptian hieroglyphics. North American ibises are bright white, while some African counterparts are shiny black.
  • Great Egret: Nesting populations have seen a decline of approximately 7 ext{%}.
  • Roseate Spoonbill: Distinctive bright pink birds with a spoon-shaped bill, showing a rare increase in population, making them a 'lone bright spot' in surveys.
• Why Count Nests Instead of Birds?
  • Challenge of Counting Birds: Birds are constantly in motion, are hard to distinguish individually, and do not wear identification tags.
  • Advantages of Counting Nests: Each wading bird species has highly distinctive nesting habits and builds unique nests. This makes identification and tracking of specific species easier for volunteers.
  • Limitations of Nest Counts: Nest counts may not account for non-breeding individuals or nests where one parent has died but the nest remains. However, they provide valuable data on the relative change in population size over time, typically expressed as percentages (e.g., nesting down by 45 ext{%} from previous years or a 10-year average).
• Ecological Significance: Wading birds serve as crucial indicators of the overall health of the Everglades ecosystem.

The Transformation of South Florida: A History of Water Management

Historical Everglades (Pre-oldsymbol{20^{ ext{th}}} Century)

• The 'River of Grass': Historically, South Florida was characterized by a massive, slow-moving 'river' of freshwater flowing south from Lake Okeechobee. This sheet flow was between 30 and 50 miles wide and nourished a vast array of unique wetland ecosystems.
• Ecosystem Diversity: This natural flow supported diverse plant communities, including cypress forests, sawgrass marshes, deep water wetland plant areas, wet grasslands, wet prairies, and marsh prairies.
• Seasonal Flooding: Much of South Florida experienced seasonal flooding, creating a dynamic environment.

Human Development and Engineering (oldsymbol{19^{ ext{th}}} and oldsymbol{20^{ ext{th}}} Centuries)

• Driving Forces: Development intensified for agriculture, real estate, and tourism, particularly accelerating after the widespread availability of air conditioning in the 1950s facilitated large-scale human migration to Florida.
• Major Engineering Projects:
  • Early oldsymbol{1900s} - Canal Construction: Large canals were dug to divert water from Lake Okeechobee eastward and westward to the coast, rather than southward. This aimed to dry out surrounding lands for agriculture (sugarcane, citrus, cattle ranching) and housing development.
  • oldsymbol{1920s} - Lake Okeechobee Dike: Following devastating hurricanes that caused widespread flooding, a massive dike was built around Lake Okeechobee to contain its waters and protect surrounding communities.
  • oldsymbol{1928} - Tamiami Trail (Hwy oldsymbol{61}): To expand economic opportunities and connect Naples (Gulf Coast) with Miami (Atlantic Coast), an elevated highway (causeway) over 100 miles long was constructed. This road effectively acted as a dam, blocking the natural southward flow of water across the Florida Peninsula.
  • oldsymbol{1940s} - Continued Canal Building: The U.S. Army Corps of Engineers, funded by federal tax dollars, continued to construct an extensive network of canals to divert water away from developed properties, thereby increasing real estate value and agricultural productivity. This represented decades and billions of dollars in federal investment and earthmoving.
  • oldsymbol{1960s} - Everglades Enclosure: Federal engineers completed the enclosure of the remaining Everglades behind earthen dikes, further controlling water flow and effectively starving large portions of the ecosystem of their historical water supply.

The Everglades Today

• Reduced Extent: The Everglades has been reduced to approximately 50 ext{%} of its original historical size.
• Land Use Transformation: The lost wetlands have been converted into highly productive agricultural lands (e.g., winter fruits and vegetables) and trillions of dollars worth of real estate, including the rapidly expanding suburbs of Fort Lauderdale, Miami, and Homestead.
• Urbanization: Developed areas, particularly along the Atlantic Coast, now extensively surround and encroach upon the Everglades, creating a strikingly sharp and linear boundary between wilderness and city.

Shifting Perspectives: A Visual Metaphor

• Southern Tip View: Imagining standing at the southern tip of the Florida peninsula and looking north, one would see the Atlantic Ocean and Miami to the right (east) and the Gulf of Mexico and Naples to the left (west). Historically, a variety of wetland communities would have been visible, with water flowing southward toward the observer.
  • Cypress Swamps: Forests adapted to flooded conditions.
  • Tree Islands: Elevated land areas within wetlands supporting distinct tree communities.
  • Sloughs: Low-lying wetland prairies.
• Early Settlements: The highest points of the landscape, primarily along the Atlantic Ridge, were the first areas to be developed for towns and houses, not initially for tourism, but because they offered protection from both hurricane storm surges and seasonal flooding from Lake Okeechobee.
• Modern Landscape: Current aerial views reveal the massive scale of the canals and the stark, straight-edged boundary between the wilderness and the dense urban and agricultural developments, a testament to the federal government's commitment to re-sculpting the landscape.

Conservation Challenges: The Florida Panther

• Species: The Florida panther, a subspecies of mountain lion, represents the apex predator in South Florida.
• Conservation Dilemma: Radio discussions highlight the complex challenges of conserving the Florida panther in a densely populated region. Conflicting interests from conservation groups, hunting advocates, ranchers, and real estate developers underscore the difficulty of balancing ecological preservation with economic and societal demands.