Everglades National Park

Everglades National Park

Everglades National Park is a U.S. National Park in Florida that protects the southern 20 percent of the original Everglades. In the United States, it is the largest tropical wilderness, the largest wilderness of any kind east of the Mississippi River, and is visited on average by one million people each year. It is the third-largest national park in the lower 48 states after Death Valley and Yellowstone. It has been declared an International Biosphere Reserve, a World Heritage Site, and a Wetland of International Importance, one of only three locations in the world to appear on all three lists.

Everglades National Park

Although most U.S. national parks preserve unique geographic features, Everglades National Park was the first created to protect a fragile ecosystem. The Everglades are a network of wetlands and forests fed by a river flowing .25 miles (0.40 km) per day out of Lake Okeechobee, southwest into Florida Bay. The Park is the most significant breeding ground for tropical wading birds in North America, contains the largest mangrove ecosystem in the western hemisphere, is home to 36 threatened or protected species including the Florida panther, the American crocodile, and the West Indian manatee, and supports 350 species of birds, 300 species of fresh and saltwater fish, 40 species of mammals, and 50 species of reptiles. The majority of South Florida's fresh water, which is stored in the Biscayne Aquifer, is recharged in the park.

Humans have lived for thousands of years in or around the Everglades, until plans arose in 1882 to drain the wetlands and develop the recovered land for agricultural and residential use. As the 20th century progressed, water flow from Lake Okeechobee was increasingly controlled and diverted to enable explosive growth of the South Florida metropolitan area. The park was established in 1934 to protect the quickly vanishing Everglades, and dedicated in 1947 as massive canal building projects were initiated across South Florida. The ecosystems in Everglades National Park have suffered significantly from human activity, and restoration of the Everglades is a politically charged issue in South Florida.

Climate

Everglades National Park has a tropical savanna climate and tropical monsoon climate, depending on location. Most of the central region has a savanna climate while regions closer to shore, especially the eastern quarter of the park has a monsoonal climate. Both climates are characterized by two seasons: wet and dry. The park's dry season lasts from December to April, when temperatures vary from 53 °F (12 °C) to 77 °F (25 °C) and humidity is low. Since water levels are low at that time, animals congregate at central water locations, providing popular opportunities for viewing the wildlife. During the wet season, from May to November, temperatures are consistently above 90 °F (33 °C) and humidity over 90 percent. Storms can drop 10 to 300 mm of rain at a time, providing half the year's average of 60 inches of rainfall in just two months.

Ecosystems

At the turn of the 20th century common concepts of what should be protected in national parks invariably included formidable geologic features like mountains, geysers, or canyons. As Florida's population began to grow significantly and urban areas near the Everglades were developed, proponents of the park's establishment faced difficulty in persuading the federal government and the people of Florida that the subtle and constantly shifting ecosystems in the Everglades were just as worthy of protection. When the park was established in 1947, it became the first area within the U.S. to protect flora and fauna native to a region as opposed to geologic scenery. The National Park Service recognizes nine distinct interdependent ecosystems within the park that constantly shift in size owing to the amount of water present and other environmental factors.

Freshwater sloughs and marl prairies

Freshwater marl prairies are similar to sloughs, but lack the slow movement of surface water; instead, water seeps through a calcitic mud called marl. Algae and other microscopic organisms form periphyton, which attaches to limestone. When it dries it turns into a gray mud. Sawgrass and other water plants grow shorter in freshwater marl than they do in peat, the other type of soil in the Everglades which is found where water remains present longer throughout the year. Marl prairies are usually under water from three to seven months of the year, whereas sloughs may remain submerged for longer than nine months and sometimes remain under water from one year to the next. Sawgrass may dominate sloughs, creating a monoculture. Other grasses, such as muhly grass (Muhlenbergia filipes) and broad-leafed water plants can be found in marl prairies. Animals living in the freshwater sloughs also inhabit in marl prairies. Marl prairies may go dry in some parts of the year; alligators play a vital role in maintaining life in remote parts of the Everglades by burrowing in the mud during the dry season, creating pools of water where fish and amphibians survive from one year to the next. Alligator holes also attract other animals who congregate to feed on smaller prey. When the region floods again during the wet season, the fish and amphibians who were sustained in the alligator holes then repopulate freshwater marl prairies.

Endangered and threatened animals

The American crocodile has notable differences from the alligator. Habitat destruction and vehicle collisions are some of the largest threats it experiences.

Thirty-six federally protected animals live in the park, some of which face grave threats to their survival.

In the United States, the American crocodile's only habitat is within South Florida. They were once overhunted for their hides. They are protected today from hunting, but are still threatened due to habitat destruction and injury from vehicle collisions when crossing roads to reach waterways. About 1,000 crocodiles live in Florida and there are roughly 50 nests in the Everglades and Biscayne National Parks. Crocodiles populations in South Florida have increased as has the number of alligators. Crocodiles were reclassified from "endangered" to "threatened" in the United States in 2007. The Florida panther is one of the most endangered mammals on earth. About 50 live in the wild, primarily in the Everglades and the Big Cypress Swamp. The biggest threats to the panther include habitat destruction from human development, vehicle collisions, inbreeding due to their limited gene pool, parasites, diseases, and mercury poisoning.

Four Everglade species of sea turtle including the Atlantic green sea turtle, the Atlantic hawksbill, the Atlantic loggerhead (Caretta caretta), and the Atlantic ridley (Lepidochelys kempii) are endangered. Also, the leatherback sea turtle (Dermochelys coriacea) is threatened. Numbers are difficult to determine, since males and juveniles do not return to their birthplace, although females lay eggs in the same location every year. Habitat loss and illegal poaching and destructive fishing practices are the biggest threats to these animals.

Two species of birds in the park are in danger of disappearing. The range of the Cape Sable seaside sparrow is restricted to Everglades National Park and the Big Cypress Swamp. In 1981 6,656 Cape Sable seaside sparrows were reported in park boundaries, but surveys over 10 years documented a decline to an estimated 2,624 birds by 2002. Attempts to return natural levels of water to the park have been controversial; Cape Sable seaside sparrows nest about a foot off the ground, and rising water levels may harm future populations, as well as threaten the endangered snail kite. The Everglades snail kite eats apple snails almost exclusively, and the Everglades is the only location in the United States where this bird of prey exists. There is some evidence that the population may be increasing, but loss of habitat and food sources keep the estimated number of these birds at several hundred.

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Chaco Culture National Historical Park

Chaco Culture National Historical Park

Chaco Culture National Historical Park

Chaco Culture National Historical Park is a United States National Historical Park hosting the densest and most exceptional concentration of pueblos in the American Southwest. The park is located in northwestern New Mexico, between Albuquerque and Farmington, in a remote canyon cut by the Chaco Wash. Containing the most sweeping collection of ancient ruins north of Mexico, the park preserves one of the United States' most important pre-Columbian cultural and historical areas.

Between AD 900 and 1150, Chaco Canyon was a major center of culture for the Ancient Pueblo Peoples. Chacoans quarried sandstone blocks and hauled timber from great distances, assembling fifteen major complexes that remained the largest buildings in North America until the 19th century. Evidence of archaeoastronomy at Chaco has been proposed, with the "Sun Dagger" petroglyph at Fajada Butte a popular example. Many Chacoan buildings may have been aligned to capture the solar and lunar cycles, requiring generations of astronomical observations and centuries of skillfully coordinated construction. 

Geology

After the Pangaean supercontinent sundered during the Cretaceous period, the region became part of a shifting transition zone between a shallow inland sea—the Western Interior Seaway—and a band of plains and low hills to the west. A sandy and swampy coastline oscillated east and west, alternately submerging and uncovering the area atop the present Colorado Plateau that Chaco Canyon now occupies. The Chaco Wash flowed across the upper strata of what is now the 400-foot (120 m) Chacra Mesa, cutting into it and gouging out a broad canyon over the course of millions of years. The mesa comprises sandstone and shale formations dating from the Late Cretaceous, which are of the Mesa Verde formation. The canyon bottomlands were further eroded, exposing Menefee Shale bedrock; this was subsequently buried under roughly 125 feet (38 m) of sediment. The canyon and mesa lie within the "Chaco Core"—which is distinct from the wider Chaco Plateau, a flat region of grassland with infrequent stands of timber. As the Continental Divide is only 15.5 miles (25 km) east of the canyon, geological characteristics and different patterns of drainage differentiate these two regions both from each other and from the nearby Chaco Slope, the Gobernador Slope, and the Chuska Valley.

Climate

An arid region of high xeric scrubland and desert steppe, the canyon and wider basin average 8 inches of rainfall annually; the park averages 9.1 inches. Chaco Canyon lies on the leeward side of extensive mountain ranges to the south and west, resulting in a rainshadow effect that fosters the prevailing lack of moisture in the region. The region sees four distinct seasons. Rainfall is most likely between July and September, while May and June are the driest months. Orographic precipitation, which results from moisture wrung out of storm systems ascending the mountain ranges around Chaco Canyon, is responsible for most of the summer and winter precipitation, and rainfall increases with higher elevation. Occasional aberrant northward excursions of the intertropical convergence zone may boost precipitation in some years.

Chaco endures remarkable climatic extremes: temperatures range between -38 to 102 °F (-39 to 39 °C), and may swing 60 °F (33 °C) in a single day. The region averages fewer than 150 frost-free days per year, and the local climate swings wildly from years of plentiful rainfall to prolonged drought. The heavy influence of the El Niño-Southern Oscillation contributes to the canyon's fickle climate.

Flora and fauna

Chacoan flora typifies that of North American high deserts: sagebrush and several species of cactus are interspersed with dry scrub forests of piñon and juniper, the latter primarily on the mesa tops. The canyon is far drier than other parts of New Mexico located at similar latitudes and elevations, and it lacks the temperate coniferous forests plentiful to the east. The prevailing sparseness of plants and wildlife was echoed in ancient times, when overpopulation, expanding cultivation, overhunting, habitat destruction, and drought may have led the Chacoans to strip the canyon of wild plants and game. It has been suggested that even during wet periods the canyon was able to sustain only 2,000 people.

Among Chacoan mammals are the plentiful coyote (Canis latrans); mule deer, elk, and pronghorn also live within the canyon, though they are rarely encountered by visitors. Important smaller carnivores include bobcats, badgers, foxes, and two species of skunk. The park hosts abundant populations of rodents, including several prairie dog towns. Small colonies of bats, are present during the summer. The local shortage of water means that relatively few bird species are present; these include roadrunners, large hawks (such as Cooper's hawks and American kestrels), owls, vultures, and ravens, though they are less abundant in the canyon than in the wetter mountain ranges to the east. Sizeable populations of smaller birds, including warblers, sparrows, and house finches, are also common. Three species of hummingbirds are present: one is the tiny but highly pugnacious rufous hummingbird, which compete intensely with the more mild-tempered black-chinned hummingbirds for breeding habitat in shrubs or trees located near water. Western rattlesnakes are occasionally seen in the backcountry, though various lizards and skinks are far more abundant.

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Biscayne National Park

Biscayne National Park

Biscayne National Park is a U.S. National Park located in southern Florida, south of Miami. The park preserves Biscayne Bay and its offshore barrier reefs. Ninety-five percent of the park is water, and the shore of the bay is the location of an extensive mangrove forest. The park covers 172,971 acres (69,999 ha) and includes Elliott Key, the park's largest island and first of the true Florida Keys, formed from fossilized coral reef. The islands farther north in the park are transitional islands of coral and sand. The offshore portion of the park includes the northernmost region of the Florida Reef, one of the largest coral reefs in the world. Biscayne National Park protects four distinct ecosystems: the shoreline mangrove swamp, the shallow waters of Biscayne Bay, the coral limestone keys and the offshore Florida Reef. The shoreline swamps of the mainland and island margins provide a nursery for larval and juvenile fish, molluscs and crustaceans. The bay waters harbor immature and adult fish, seagrass beds, sponges, soft corals, and manatees. The keys are covered with tropical vegetation including endangered cacti and palms, and their beaches provide nesting grounds for endangered sea turtles. Offshore reefs and waters harbor more than 200 species of fish, pelagic birds, whales and hard corals. Sixteen endangered species including Schaus' swallowtail butterflies, smalltooth sawfish, manatees, and green and hawksbill sea turtles may be observed in the park. Biscayne also has a small population of threatened American crocodiles and a few American alligators.

The people of the Glades culture inhabited the Biscayne Bay region as early as 10,000 years ago before rising sea levels filled the bay. The Tequesta people occupied the islands and shoreline from about 4,000 years before the present to the 16th century, when the Spanish took possession of Florida. Reefs claimed ships from Spanish times through the 20th century, with more than 40 documented wrecks within the park's boundaries. While the park's islands were farmed during the 19th and early 20th centuries, their rocky soil and periodic hurricanes made agriculture difficult to sustain. In the early 20th century the islands became secluded destinations for wealthy Miamians who built getaway homes and social clubs. Mark C. Honeywell's guesthouse on Boca Chita Key was the area's most elaborate private retreat, featuring a mock lighthouse. The Cocolobo Cay Club was at various times owned by Miami developer Carl G. Fisher, yachtsman Garfield Wood, and President Richard Nixon's friend Bebe Rebozo, and was visited by four United States presidents. The amphibious community of Stiltsville was established in the 1930s in the shoals of northern Biscayne Bay, taking advantage of its remoteness from land to offer offshore gambling and alcohol during Prohibition. Following the Cuban Revolution of 1959, Elliott Key was used as a training ground for infiltrators into Fidel Castro's Cuba by the Central Intelligence Agency and by Cuban exile groups.

Originally proposed for inclusion in Everglades National Park, Biscayne Bay was cut from the proposed park to ensure Everglades' establishment. It remained undeveloped until the 1960s, when a series of proposals were made to develop the keys in the manner of Miami Beach, and to construct a deepwater seaport for bulk cargo, along with refinery and petrochemical facilities on the mainland shore of Biscayne Bay. Through the 1960s and 1970s, two fossil-fueled power plants and two nuclear power plants were built on the bay shores. A backlash against development led to the 1968 designation of Biscayne National Monument. The preserved area was expanded by its 1980 re-designation as Biscayne National Park. The park is heavily used by boaters, and apart from the park's visitor center on the mainland, its land and sea areas are accessible only by boat.

Climate

Biscayne's tropical climate reflects its location in extreme South Florida. Southern Miami-Dade County is classified as tropical savanna in the Köppen-Geiger system. Seasons may be divided into the November–April dry season and the May–October wet season. Dry season temperatures average between 66 and 76 °F (19 and 24 °C) with an average monthly rainfall of 2.1 inches (53 mm). Wet season temperatures average between 76 and 85 °F (24 and 29 °C) with an average monthly rainfall of 5.39 inches (137 mm). The wet season roughly coincides with hurricane season, with frequent thunderstorms. 

Like many locations in southern Florida, Biscayne National Park is affected by hurricanes every few years. Most storms require temporary closings and occasional repairs to park facilities. A direct hit by a powerful hurricane can produce severe consequences, primarily by its impact on human interventions in the environment rather than on the natural environment of the park, which is well-adapted to these events.  Significant hurricanes to strike Biscayne include storms in 1835 and 1904, the 1906 Florida Keys hurricane, the 1926 Miami hurricane, the 1929 Bahamas hurricane, the 1935 Labor Day hurricane, the 1935 Yankee hurricane, the 1941 Florida hurricane, the 1945 Southeast Florida hurricane, the 1948 Miami hurricane, Hurricane King in 1950, Hurricane Donna in 1960. Hurricane Cleo in 1964, and Hurricane Andrew in 1992. The park can be affected by wave action from more distant tropical storms such as 2012's Hurricane Sandy, which damaged facilities on Elliott Key.

Exploration

Juan Ponce de León explored the area in 1513, discovering the Florida Keys and encountering the Tequesta on the mainland. Other Spanish explorers arrived later in the 16th century and Florida came under Spanish rule. The Tequesta were resettled by the then-Spanish government in the Florida Keys, and the South Florida mainland was depopulated. Ponce de León referred to the bay as "Chequescha" after its inhabitants, becoming "Tequesta" by the time of Spanish governor Pedro Menéndez de Avilés later in the century. The present name has been attributed to a shipwrecked Basque sailor known as the "Biscaino" or "Viscayno" who lived in the area for a time, or to a more general allusion to the Bay of Biscay. Spanish treasure fleets regularly sailed past the Florida Keys and were often caught in hurricanes. There are 44 documented shipwrecks in the park from the 16th through the 20th centuries. At least two 18th-century Spanish ships were wrecked in the park area. The Spanish galleon Nuestra Senora del Popolo is believed to have been wrecked in park waters in 1733, though the site has not been found. HMS Fowey was wrecked in 1748 in what is now Legare Anchorage, at some distance from the Fowey Rocks. The discovery of the ship in 1975 resulted in a landmark court case that established the wreck as an archaeological site rather than a salvage site. 43 wrecks are included on the National Register of Historic Places in the Offshore Reefs Archeological District, which extends for 30 mi (48 km) along the seaward side of the Biscayne National Park keys. During the 18th century, Elliott Key was the reputed base of two different pirates, both of whom were called Black Caesar, commemorated by Caesar's Creek between Elliott and Old Rhodes Key.

Ecology

South Florida is a transitional zone between the Nearctic and Neotropical ecozones, resulting in a wide variety of plant and animal life. The intersection of ecozones brings opportunities for visitors to see species, particularly birds, that are not seen elsewhere in North America. The park includes four distinct ecosystems, each supporting its own flora and fauna. Mangrove swamp, lagoon, island key and offshore reef habitats provide diversity for many species. In this semi-tropical environment, the seasons are differentiated mainly by rainfall. Warm to hot and wet summers bring occasional tropical storms. Though only marginally cooler, the winters tend to be relatively drier. Bay salinity varies accordingly, with lower salinity levels in the wet summer, trending to more fresh water on the west side where new fresh water flows in.

Hundreds of species of fish are present in park waters, including more than fifty crustacean species ranging from isopods to giant blue land crabs, about two hundred species of birds and about 27 mammal species, both terrestrial and marine. Molluscs include a variety of bivalves, terrestrial and marine snails, sea hares, sea slugs and two cephalopods, the Caribbean reef octopus and the Caribbean reef squid.way between North American, the Caribbean islands, and South America. Many southbound land birds stop in the fall at Bill Baggs Cape Florida State Park, just north of the park on Key Biscayne, before venturing across the open waters of Biscayne Bay. Northbound spring migrants do likewise on Elliott Key. Most of the small passerine migrants are warblers, with ovenbirds, palm warblers, American redstarts, common yellowthroats, prairie warblers, worm-eating warblers and black-throated blue warblers accounting for the majority. Migrant raptors include short-tailed hawks, sharp-shinned hawks, merlins, peregrine falcons and swallow-tailed kites, while bald eagles and ospreys nest in the park. Both white-tailed and red-tailed tropicbirds are seen in the park, as are American flamingos, with some of the latter probably escaped captive birds.

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