Florida great blue heron

Ecoregions of Florida

Florida can be divided into three main eco-regions as follows:

Southeastern Plains

Most of the northern Panhandle and much of northwestern peninsular Florida lies within this eco-region. Geologically speaking this region is characterized by sedimentary rock laid down in the Cretaceous and Tertiary periods and is younger than the igneous and metamorphic rock of the adjoining Piedmont. The landscape is dominated by a mixture of agricultural land (both cropland and pastureland) and southern hardwood forests of oak and hickory as well as pine trees. This is the area that is richest in breeding and wintering land birds in Florida. Many species that occur here are not found any farther south. Among these species are white-breasted nuthatch year-round, eastern wood-pewee and Acadian flycatcher in summer, and winter wrens and brown creepers in winter.

Southern Coastal Plain

This eco- region covers most of peninsular Florida as well as the coastal strip of the Panhandle. It is characterized by flat plains containing numerous swamps, marshes, and lakes. With its largely subtropical climate, the southern coastal plain has milder weather and therefore a longer growing season than coastal areas to the north and west. Once dominated by forests of beech, sweet gum, magnolia, oak, and pine, this region has been drastically altered by urban development (especially along the Atlantic and Gulf coasts), the conversion of scrub and forest to beef pastureland and citrus groves, and the replacement of longleaf pine forests by faster-growing slash and sand pines. This region is inhabited by large numbers of long-legged wading birds and specialty species such as crested caracara, Florida scrub-jay, and the Florida race of burrowing owl.

Southern Florida Coastal Plain

Almost the whole of southern Florida south of Lake Okeechobee lies within this eco-region. Its frost-free climate differentiates this region from most other eco-regions in the United States. Like the southern coastal plain to the north, this region is characterized by flat plains, wet soils, marshes, cypress swamps, mangrove swamps, and the sawgrass prairies of the Everglades. Even though a significant percent of this area is now protected, it has undergone a dramatic alteration within the past century in matters of water quality and water flow. Attempts to reverse the resulting biological degradation are now in progress. This region has also suffered perhaps more than any other in Florida from the effects of alien plant species such as Brazilian pepper, Australian punk tree (melaleuca) and Australian pine (casuarina).  Some of the largest wading bird colonies in the country occur here, as well as most of Florida’s breeding populations of smooth-billed anis, snail kites, and white-tailed kites.

Although the highest point in Florida is less than 350 feet above sea level the state contains a surprising number of  varied habitats that make it a good place for birds and bird watching.  The following can be regarded as the main eco-regions or habitat types found in Florida.

Beaches and Intertidal Areas

Florida is justly famous for its magnificent beaches which cover a significant portion of the Gulf Coast and Atlantic coast. Despite the onslaught of millions of beach-goers every year, this habitat remains an extremely important one for birds, even though beachfront development has irreversibly destroyed huge areas of dune habitats. Beaches and barrier islands provide critical nesting habitat for  residents such as Sandwich and royal terns, black skimmers, American oystercatchers, snowy and Wilson’s plovers and summer visitors such as least terns. During winter Florida’s beaches are home to huge numbers of shorebirds including black-bellied and semipalmated plovers, spotted sandpiper, sanderling, ruddy turnstone, dunlin, red knot, western and least sandpipers, short-billed dowitcher, willet, marbled godwit, whimbrel, and even the occasional long-billed curlew. During migration this habitat also attracts semipalmated and white-rumped sandpipers. Large numbers of laughing and ring-billed gulls winter on Florida’s beaches as well as smaller numbers of Bonaparte’s and herring gulls and a few great and lesser black-backed gulls. Migrant common and black terns roost in these areas, sometimes in large numbers. Several species of herons and egrets, including reddish egrets, forage along Florida’s beaches.

Mangrove Swamps

Mangroves are tropical trees that cannot withstand a cold climate so they are restricted to the central and southern portions of the state. Three species are present; red mangrove, black mangrove and white mangrove. A fourth species found in these swamps, buttonwood, is not a mangrove in the strict sense. In some areas mangroves can grow to 20 or even 30 feet tall. The most extensive mangrove swamps are found in extreme southern Florida and along the Keys. Several species of birds are particularly associated with this habitat including the white-crowned pigeon, mangrove cuckoo, gray kingbird and black-whiskered vireo as well as the Florida race of the prairie warbler and Cuban race of the yellow warbler. In addition mangroves provide an important habitat for many species of migrant and wintering warblers, as well as nesting habitat for numerous species including magnificent frigatebird (Dry Tortugas only), brown pelican, wood stork, great, snowy, and reddish egrets, roseate spoonbill, and little blue and tricolored herons. Even bald eagles and ospreys will sometimes nest in mangroves.

Salt Marshes

This habitat type is found exclusively in coastal areas and supports its own unique set of bird species. Several species of sedges and rushes grow in salt marshes including cordgrass (otherwise known as “spartina”) and needle rush. Clapper rails and willets nest exclusively in this habitat while other breeding residents include seaside sparrow and marsh wren, red-winged blackbird and boat-tailed grackle. Many other species use it as a rich feeding ground.  These include the double-crested cormorant, brown pelican, great blue heron, little blue and tricolored herons, great and snowy egrets, yellow-crowned night-heron, green heron, white ibis, wood stork, American oystercatcher, and black skimmer. In winter northern harriers hunt over saltmarshes and other species to be found in this habitat include both Nelson’s and saltmarsh sharp-tailed sparrows, swamp sparrow, sedge wren, common yellowthroat, greater and lesser yellowlegs and belted kingfisher.

Open Ocean

Peninsular Florida is almost completely surrounded by saltwater, with the Gulf of Mexico to the west, Atlantic Ocean to the East, and the Caribbean Sea to the south. These are the realms of various species of seabirds. Although a few of these species can be observed from shore, particularly after the passage of a tropical storm or hurricane, the best way to see them is to embark on a pelagic tripon a boat. In winter large numbers of northern gannets can be seen in Florida’s waters, as well as small numbers of parasitic and pomarine jaegers and both red-necked and red phalaropes. At other times of the year several species of shearwaters can be found including Audubon’s, Cory’s, and great shearwaters, which are the most numerous species, as well as a few Manx and sooty shearwaters. Black-capped petrels are decidedly rare but good numbers of storm-petrels can sometimes be found, the most numerous of which are Wilson’s storm-petrels, followed by Leach’s and band-rumped storm-petrels. Other pelagic species that can be seen in Florida include both brown and masked boobies, brown noddy, and sooty and bridled terns.

Oak Forests

Oak forests dominate large areas of Florida and have taken over in many instances after the removal of native pine forests by logging. These forests are characterized by live oaks which can grow to a massive size and can be extremely long lived, laurel oaks, water oaks and turkey oaks.  Permanent avian residents of these forests include wild turkey, northern bobwhite, red-shouldered and red-tailed hawks, black and turkey vultures, common ground-dove, mourning dove, pileated, downy, and red-bellied woodpeckers, northern flicker, blue jay, Carolina chickadee, tufted titmouse, Carolina wren, blue-gray gnatcatcher, brown thrasher, white-eyed vireo, northern cardinal, and eastern towhee.  During the summer months these are joined by swallow-tailed kite, broad-winged hawk, chuck-will’s widow, summer tanager, and great crested flycatcher. In winter great flocks of yellow-rumped and palm warblers descend on these forests with smaller numbers of orange-crowned warblers, blue-headed vireos, and ruby-crowned kinglets among them. During spring and fall oak forests play host to large numbers of passerine migrants including dozens of species of wood warblers, several vireos, thrushes, tanagers, grosbeaks, buntings, sparrows, and orioles.

Pine Forests

Before human settlement pine forests of various types covered a significant portion of Florida. Nowadays a significant percentage of these forests has been destroyed. Particularly imperiled is virgin longleaf pine forest which supports a set of unique species. Forests of slash and longleaf pine, often referred to as “flatwoods” due to their topography, are heavily influenced by fire which maintains their open nature and thins the understory dominated by saw palmettos and wire grass.  Nowadays, fire suppression has resulted in many flatwood areas becoming overgrown with oaks and other species which diminishes their value to certain species of birds.

Permanent residents of pine flatwoods in Florida include red-shouldered hawk, northern bobwhite, common ground-dove, eastern bluebird, eastern meadowlark, Bachman’s sparrow, brown-headed nuthatch, pileated, hairy, red-cockaded, red-bellied, and red-headed woodpeckers, northern flicker, American crow, Carolina chickadee, eastern towhee, and pine warbler. In summer chuck-will’s-widow, common nighthawk, yellow-billed cuckoo, yellow-throated vireo, and summer tanager can also be found. And winter visitors include yellow-bellied sapsucker, eastern phoebe, American robin, gray catbird, and yellow-rumped warbler.

Oak Scrub

This habitat is found largely on sandy soils along interior ridges such as the Lake Wales Ridge and also along both coastlines. It is dominated by small oaks and other shrubs which are generally less than 15 feet tall. Oak scrub is dependent on fire for its survival and is now becoming a much reduced and threatened habitat both from modern day fire suppression and loss due to development.  If not burned on a regular basis (at least once every 15 years) then succession takes over and oak scrub reverts to sand pine forest. This transition eliminates populations of Florida scrub-jays, the oak scrubs most threatened inhabitant. Other species typically found in oak scrub include northern bobwhite, northern mockingbird, white-eyed vireo, and eastern towhee. With the transition to sand pine forest birds such as blue jay, great crested flycatcher, pine warbler, and eastern screech-owl make an appearance.

Prairies

This habitat type can be divided into wet prairies and dry prairies. Wet prairies are shallow marshes such as those found in the Everglades (often referred to as sawgrass prairie). Dry prairies are found on well-drained sandy soils and are dominated by saw palmettos and grass. These areas are home to several species that have disjunct populations in Florida. The resident race of the sandhill crane occurs in prairies throughout the central part of the state but has also adapted to living on golf courses and retention ponds in the face of increasing human development. The Florida race of the burrowing owl has increased in recent decades after deforested areas have reverted back to prairies favoring this subterranean-nesting species. Crested caracaras, with a population of about 150 pairs, also occur mainly in the central part of the state on dry prairies where they nest in isolated cabbage palms. Much of this habitat has been converted to ranch land which the caracaras still frequent. Finally, the Florida grasshopper sparrow, with a population of only about 100 pairs, is an endangered, endemic race which is restricted to dry prairies in the south-central portion of the state.

Hammocks

Hammocks are islands of vegetation surrounded by either marshes or prairies. They can be dominated by various species of palms (such as those hammocks found at Merritt Island National Wildlife Refuge), deciduous forest trees such as oaks or West Indian hardwoods as in the case of the hammocks found in the Everglades. The latter contain tropical trees such as gumbo limbo, poisonwood, mahogany, and several species of figs. Bird species breeding in hammocks are roughly equivalent to those found in larger stands of the equivalent vegetation type. Oak hammocks therefore have many species typical of oak forests such as red-shouldered hawk, wild turkey, barred owl, red-bellied woodpecker, and great crested flycatcher. Tropical hammocks support several Caribbean species that barely maintain a toehold in the United States such as white-crowned pigeon and black-whiskered vireo. Because of their isolated nature, hammocks are excellent places to look for migrant land birds.

Freshwater Marshes, Rivers, and Lakes

These are common habitat types found throughout Florida and are extremely important feeding and nesting sites for a wide variety of birds.  Marshes range from seasonally flooded areas which are created during Florida’s wet season (June to October) to more permanent deeper bodies of water. The best example of a freshwater marsh in the state is the Everglades, a unique ecosystem which used to cover over 7,500 square miles but now covers little more then half of that due to drainage and development.

Due to the presence of the potholed limestone Floridian Plateau, lakes are extremely numerous in Florida, numbering at least 8,000 throughout the state. There are more spring-fed rivers in Florida than in any other state in the country and the total daily discharge from these springs is thought to be at least eight billion gallons of water.

Typical breeding species in Florida’s freshwater ecosystems include great blue heron, great, snowy, and cattle egrets, least bittern, little blue and tricolored herons, green heron, white and glossy ibises, black-crowned night-heron, anhinga, mottled duck, purple gallinule, common moorhen, king rail, osprey, bald eagle, limpkin, black-necked stilt, common yellowthroat, red-winged blackbird, and boat-tailed grackle. During migration periods many species of shorebirds may be present including solitary, pectoral, least and stilt sandpipers, greater and lesser yellowlegs, and Wilson’s phalarope. In winter thousands of ducks descend on Florida’s marshes, and birds such as American bittern, Wilson’s snipe, long-billed dowitcher, belted kingfisher, marsh and sedge wrens, and swamp sparrow can also be found.

Cypress Swamps

Swamps are heavily wooded areas that are usually at least partly flooded. In Florida many swamps are dominated by stands of bald cypress and can vary in extent from just a few acres to large areas such as Big Cypress Swamp, which borders the Everglades. Other swamp trees include tupelo, sweet gum, bay, and red maple. Many of the species listed under freshwater marshes can also be found nesting in swamps, such as most of the herons, egrets, and ibises and especially wood storks. Other species typical of swamps include anhinga, limpkin, barred owl, swallow-tailed kite, osprey, bald eagle, pileated woodpecker, northern parula, and white-eyed vireo. During migration periods and in winter swamps become extremely important habitats for large numbers of land birds.

Cities and Towns

Florida’s burgeoning human population has created a habitat that is hostile to many bird species, although some have adapted surprisingly well to the urban jungle. It is not uncommon to find cattle egrets and white ibises foraging on suburban lawns and many species of herons and egrets can be seen in retention ponds and roadside ditches. Common native land birds found in towns and cities include northern mockingbird, northern cardinal, blue jay, Carolina wren, tufted titmouse, common grackle, red-bellied woodpecker, and mourning dove.

There are probably more species of introduced alien species in Florida than in any other state in the nation and many of these have become established to the extent that they are “countable” under the American Birding Association’s listing rules. These include not only the ubiquitous house sparrow, European starling, and rock dove but also the Eurasian collared-dove, which is increasing at an explosive rate, monk parakeet, yellow-chevroned and white-winged parakeets, and the much more localized spot-breasted oriole and red-whiskered bulbul, both of which are found exclusively in the Miami area. In addition there are several species which are well on their way to becoming established enough that they will become “countable” in the near future including the common myna, black-hooded parakeet, blue-crowned parakeet, and muscovy duck.

 

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