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47-446: The lake is home to a wide variety of species and is considered to support one of the state's densest populations of alligators . Drivers on the bridge across the lake are likely to see eagles ( osprey and bald eagles ) perched on the light posts watching for fish. During the 1960s, the toll of decades of abuse and neglect was very apparent. Wastewater discharged directly into the lake, stormwater discharges from surrounding communities,

94-401: A "death roll", spinning or convulsing wildly until bite-sized chunks are torn off. Critical to the alligator's ability to initiate a death roll, the tail must flex to a significant angle relative to its body. An alligator with an immobilized tail cannot perform a death roll. Most of the muscle in an alligator's jaw evolved to bite and grip prey. The muscles that close the jaws are powerful, but

141-406: A Louisiana swamp in 1987. Alligators are raised commercially for their meat and their skin, which when tanned is used for the manufacture of luggage , handbags , shoes, belts , and other leather items. Alligators also provide economic benefits through the ecotourism industry. Visitors may take swamp tours, in which alligators are a feature. Their most important economic benefit to humans may be

188-451: A breeding pair of Chinese alligators. Large male alligators are solitary territorial animals. Smaller alligators can often be found in large numbers close to each other. The largest of the species (both males and females) defend prime territory; smaller alligators have a higher tolerance for other alligators within a similar size class. Alligators move on land by two forms of locomotion, referred to as "sprawl" and "high walk". The sprawl

235-446: A giant Miocene genus that grew to 12 m (39 ft) and the equally large Mourasuchus , which had a wide duck -like snout. Caimans are predators and, like alligators and crocodiles, their diet largely consists of fish. Caimans also hunt insects, birds, small mammals and reptiles. Due to their large size and ferocious nature, caimans have few natural predators within their environments. Humans are their main predators, because

282-419: A large nest in which to lay their eggs. The nests can be more than 1.5 m (4.9 ft) wide. Female caimans lay between 10 and 50 eggs, which hatch within about six weeks. Once they have hatched, the mother caiman takes her young to a shallow pool of water, where they can learn how to hunt and swim. The juveniles of spectacled caiman have been shown to stay together in pods for up to 18 months. Caimaninae

329-497: A length of 1.8 m (6 ft). The mating season is in late spring. In April and May, alligators form so-called "bellowing choruses". Large groups of animals bellow together for a few minutes a few times a day, usually one to three hours after sunrise. The bellows of male American alligators are accompanied by powerful blasts of infrasound . Another form of male display is a loud head-slap. In 2010, on spring nights alligators were found to gather in large numbers for group courtship,

376-439: A meal by up to four times its basal metabolic rate. Alligators also have highly folded mucosa in the lining of the intestines to further aid in the absorption of nutrients. The folds result in greater surface area for the nutrients to be absorbed through. Alligators also have complex microbiomes that are not fully understood yet, but can be attributed to both benefits and costs to the animal. These microorganisms can be found in

423-557: A meal during brumation will begin a process called autophagy , where the animal begins to consume its fat reserves to maintain its body weight until it can acquire a sufficient meal. There is also fluctuation in the level of bacterial taxa populations in the alligator's microbial community between seasons which helps the alligator cope with different rates of feeding and activity. Like other crocodilians, alligators have an armor of bony scutes. The dermal bones are highly vascularised and aid in calcium balance, both to neutralize acids while

470-490: Is cladistically defined as Caiman crocodylus (the spectacled caiman ) and all species closer to it than to Alligator mississippiensis (the American alligator ). This is a stem-based definition for caimaninae, and means that it includes more basal extinct caimanine ancestors that are more closely related to living caimans than to alligators . The clade Jacarea includes the most derived caimans, being defined as

517-787: Is 360 kg (790 lb) and 4 m (13 ft), but they sometimes grow to 4.4 m (14 ft) long and weigh over 450 kg (990 lb). The largest ever recorded, found in Louisiana, measured 5.84 m (19.2 ft). The Chinese alligator is smaller, rarely exceeding 2.1 m (7 ft) in length. Additionally, it weighs considerably less, with males rarely over 45 kg (100 lb). Adult alligators are black or dark olive-brown with white undersides, while juveniles have bright yellow or whitish stripes which sharply contrast against their dark hides, providing them additional camouflage amongst reeds and wetland grasses. No average lifespan for an alligator has been measured. One of

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564-469: Is a forward movement with the belly making contact with the ground and is used to transition to "high walk" or to slither over wet substrate into water. The high walk is an up-on-four-limbs forward motion used for overland travel with the belly well up from the ground. Alligators have also been observed to rise up and balance on their hind legs and semi-step forward as part of a forward or upward lunge. However, they can not walk on their hind legs. Although

611-485: Is a large reptile in the genus Alligator of the family Alligatoridae of the order Crocodilia . The two extant species are the American alligator ( A. mississippiensis ) and the Chinese alligator ( A. sinensis ). Additionally, several extinct species of alligator are known from fossil remains. Alligators first appeared during the late Eocene epoch about 37 million years ago. The name "alligator"

658-517: Is found in only the Yangtze River valley and parts of adjacent provinces and is extremely endangered, with only a few dozen believed to be left in the wild. Far more Chinese alligators live in zoos around the world than can be found in the wild. Rockefeller Wildlife Refuge in southern Louisiana has several in captivity in an attempt to preserve the species. Miami MetroZoo in Florida also has

705-598: Is likely an anglicized form of el lagarto , the Spanish term for "the lizard", which early Spanish explorers and settlers in Florida called the alligator. Early English spellings of the name included allagarta and alagarto . Alligators and caimans split in North America during the early Tertiary or late Cretaceous (about 53 million to about 65 million years ago). The Chinese alligator split from

752-519: Is the largest caiman species in the world and is found in the slow-moving rivers and lakes that surround the Amazon basin. The smallest species is the Cuvier's dwarf caiman ( Paleosuchus palpebrosus ), which grows to 1.2 to 1.5 m (3.9 to 4.9 ft) long. There are six different species of caiman found throughout the watery jungle habitats of Central and Southern America. The average length for most of

799-622: The Alligatoridae family , the other being alligators . Caimans are native to Central and South America and inhabit marshes , swamps , lakes , and mangrove rivers. They have scaly skin and live a fairly nocturnal existence. They are relatively small-sized crocodilians with an average maximum weight of 6 to 40 kg (13 to 88 lb) depending on species, with the exception of the black caiman ( Melanosuchus niger ), which can grow more than 4 m (13 ft) in length and weigh in excess of 450 kg (1,000 Ib). The black caiman

846-634: The American alligator about 33 million years ago and probably descended from a lineage that crossed the Bering land bridge during the Neogene . The modern American alligator is well represented in the fossil record of the Pleistocene . The alligator's full mitochondrial genome was sequenced in the 1990s. The full genome , published in 2014, suggests that the alligator evolved much more slowly than mammals and birds. The genus Alligator belongs to

893-714: The Florida Department of Transportation and the Florida Fish and Wildlife Conservation Commission to develop a plan for restoring the lake. The Friends and the District staff, working closely with the Florida Department of Transportation and the Florida Fish and Wildlife Conservation Commission, began to determine the most environmentally sound and economically feasible methods of restoring

940-419: The apex predator throughout their distribution. In this role as a top predator, it may determine the abundance of prey species, including turtles and nutrias. As humans encroach into their habitat, attacks are few but not unknown. Alligators, unlike the large crocodiles , do not immediately regard a human upon encounter as prey, but may still attack in self-defense if provoked. Alligators generally mature at

987-484: The crocodile , with minor differences in morphology and enzyme activity. Alligators have a two-part stomach, with the first smaller portion containing gastroliths . It is believed this portion of the stomach serves a similar function as it does in the gizzard of some species of birds, to aid in digestion. The gastroliths work to grind up the meal as alligators will take large bites or swallow smaller prey whole. This process makes digestion and nutrient absorption easier once

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1034-816: The subfamily Alligatorinae , which is the sister taxon to Caimaninae (the caimans ). Together, these two subfamilies form the family Alligatoridae . The cladogram below shows the phylogeny of alligators. Caimaninae Ceratosuchus burdoshi † Hassiacosuchus haupti † Navajosuchus mooki † Wannaganosuchus brachymanus † Arambourgia gaudryi † Allognathosuchus polyodon † Allognathosuchus wartheni † Procaimanoidea kayi † Alligator prenasalis † Alligator mcgrewi † Alligator olseni † Alligator sinensis Chinese alligator Alligator thomsoni † Alligator mefferdi † Alligator mississippiensis American alligator An average adult American alligator's weight and length

1081-406: The alligator has a heavy body and a slow metabolism , it is capable of short bursts of speed, especially in very short lunges. Alligators' main prey are smaller animals they can kill and eat with a single bite. They may kill larger prey by grabbing it and dragging it into the water to drown. Alligators consume food that cannot be eaten in one bite by allowing it to rot or by biting and then performing

1128-547: The animal cannot breathe underwater and to provide calcium for eggshell formation. Alligators have muscular, flat tails that propel them while swimming. The two kinds of white alligators are albino and leucistic . These alligators are practically impossible to find in the wild. They could survive only in captivity and are few in number. The Aquarium of the Americas in New Orleans has leucistic alligators found in

1175-474: The animals have been hunted for their meat and skin. Jaguars , anacondas and crocodiles are the only other predators of caimans, although they usually prey on the smaller specimens or specific species of caiman such as the Spectacled Caiman and Yacare caiman . During summer or droughts, caimans may dig a burrow and go into a form of summer hibernation called aestivation . Female caimans build

1222-781: The animals into attacking. In Florida, feeding wild alligators at any time is illegal. If fed, the alligators will eventually lose their fear of humans and will learn to associate humans with food. The type of food eaten by alligators depends upon their age and size. When young, alligators eat fish, insects, snails , crustaceans , and worms . As they mature, progressively larger prey is taken, including larger fish such as gar , turtles, and various mammals, particularly nutrias and muskrats, as well as birds, deer, and other reptiles. Their stomachs also often contain gizzard stones . They will even consume carrion if they are sufficiently hungry. In some cases, larger alligators are known to ambush dogs, Florida panthers and black bears , making them

1269-510: The construction of berms that segregated the lake from parts of its floodplain, and a causeway that reduced the lake's connection with the St. Johns River all took their toll on the ecosystem. The discharges resulted in significant algae growth , fish kills , and a thick layer of muck more than 9½ feet deep in some areas sitting on the bottom of the lake that now averages only six feet in depth. The berm construction aggravated this problem by limiting

1316-440: The control of nutrias and muskrats . Alligator meat is also consumed by humans. While there are rules of thumb for distinguishing alligators from crocodiles, all of them admit exceptions. Such general rules include: Caimans A caiman ( / ˈ k eɪ m ə n / (also spelled cayman ) from Taíno kaiman ) is an alligatorid belonging to the subfamily Caimaninae , one of two primary lineages within

1363-462: The food reaches the second portion of the stomach. Once an alligator's meal has been processed it will move on to the second portion of the stomach which is highly acidic. The acidity of the stomach has been observed to increase once digestion begins. This is due to the increase in CO 2 concentration of the blood, resulting from the right to left shunting of the alligators heart. The right to left shunt of

1410-414: The former tend to produce males and the latter, females. The baby alligator's egg tooth helps it get out of its egg during hatching time. The natural sex ratio at hatching is five females to one male. Females hatched from eggs incubated at 30 °C (86 °F) weigh significantly more than males hatched from eggs incubated at 34 °C (93 °F). The mother defends the nest from predators and assists

1457-421: The hatchlings to water. She will provide protection to the young for about a year if they remain in the area. Adult alligators regularly cannibalize younger individuals, though estimates of the rate of cannibalism vary widely. In the past, immediately following the outlawing of alligator hunting , populations rebounded quickly due to the suppressed number of adults preying upon juveniles, increasing survival among

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1504-501: The heart in alligators means the circulatory system will recirculate blood through the body instead of back to the lungs. The re-circulation of blood leads to higher CO 2 concentration as well as lower oxygen affinity. There is evidence to suggest that there is increased blood flow diverted to the stomach during digestion to facilitate an increase in CO 2 concentration which aids in increasing gastric acid secretions during digestion. The alligator's metabolism will also increase after

1551-468: The high surface area of the mucosa folds of the intestines, as well as throughout the digestive tract. Benefits include better total health and stronger immune system. However alligators are still vulnerable to microbial infections despite the immune boost from other microbiota. During brumation the process of digestion experiences changes due to the fasting most alligators experience during these periods of inactivity. Alligators that go long enough without

1598-420: The inspired air must move back out the same way it came in. In contrast, air in alligator lungs makes a circuit, moving in only one direction through the parabronchi . The air first enters the outer branch, moves through the parabronchi, and exits the lung through the inner branch. Oxygen exchange takes place in extensive vasculature around the parabronchi. The alligator has a similar digestive system to that of

1645-516: The lake to act as a natural filter. The removal of this berm also increases the lake's flood buffering capacity as well as providing habitat to a wide variety of life. In January 2008 the Army Corps of Engineers , the Florida Department of Transportation , and others contracted to have the State Road 417 bridge rebuilt. The re-opening of channel B and the removal of about a mile of causeway

1692-506: The lake's ability to cleanse itself. During the 1990s studies were conducted of water circulation patterns, storm-water runoff into the lake, the impacts of the State Road 417 bridge, sediments within the lake, and land management plans for adjacent public properties. With this data in hand, The Friends of Lake Jesup and the St. Johns River Water Management District staff worked closely with

1739-459: The lake. Since that time the water district brought about 3,850 acres (15.6 km) around the lake into public ownership and has plans for acquiring an additional 4,700 acres (19 km) of floodplain around the lake as part of the restoration process and to ensure the health of the lake into the future. In the spring of 1996 a 2-mile (3.2 km) berm on the north side of the lake was removed, reuniting 300 acres (1.2 km) of floodplain with

1786-445: The largest alligator population. The majority of American alligators inhabit Florida and Louisiana, with over a million alligators in each state. Southern Florida is the only place where both alligators and crocodiles live side by side. American alligators live in freshwater environments, such as ponds , marshes , wetlands , rivers , lakes , and swamps , as well as in brackish water . When they construct alligator holes in

1833-1012: The last common ancestor of Caiman latirostris (Broad-snouted caiman), Caiman crocodilus (Spectacled caiman), Caiman yacare (Yacare caiman), Melanosuchus niger (Black caiman), and all its descendants. Below is a cladogram showing the phylogeny of Caimaninae, modified from Hastings et al. (2013). † Stangerochampsa mccabei † Brachychampsa montana † Brachychampsa sealeyi Alligatorinae † Culebrasuchus mesoamericanus † Eocaiman cavernensis † Tsoabichi greenriverensis Paleosuchus palpebrosus Cuvier's dwarf caiman Paleosuchus trigonatus Smooth-fronted caiman † Centenariosuchus gilmorei † Purussaurus neivensis † Mourasuchus spp. † Orthogenysuchus olseni Caiman crocodilus Spectacled caiman Caiman yacare Yacare caiman Caiman latirostris Broad-snouted caiman † Caiman lutescens † Melanosuchus fisheri Melanosuchus niger Black caiman Here

1880-437: The muscles for opening their jaws are weak. As a result, an adult human can hold an alligator's jaws shut bare-handed. It is common to use several wraps of duct tape to prevent an adult alligator from opening its jaws when being handled or transported. Alligators are generally timid towards humans and tend to walk or swim away if one approaches. This may encourage people to approach alligators and their nests, which can provoke

1927-807: The oldest recorded alligator lives was that of Saturn , an American alligator who was hatched in 1936 in Mississippi and spent nearly a decade in Germany before spending the majority of his life at the Moscow Zoo , where he died at the age of 83 or 84 on 22 May 2020. Another one of the oldest lives on record is that of Muja , an American alligator who was brought as an adult specimen to the Belgrade Zoo in Serbia from Germany in 1937. Although no valid records exist about his date of birth, as of 2012, he

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1974-557: The other caiman species is about 2 to 2.5 m (6.6 to 8.2 ft) long. Caimans are distinguished from alligators, their closest relatives, by a few defining features: a lack of a bony septum between the nostrils, ventral armor composed of overlapping bony scutes formed from two parts united by a suture, and longer and sharper teeth than alligators, plus caimans tend to be more agile and crocodile-like in their movements. The calcium rivets on caiman scales make their hides stiffer. Several extinct forms are known, including Purussaurus ,

2021-547: The so-called "alligator dances". In summer, the female builds a nest of vegetation where the decomposition of the vegetation provides the heat needed to incubate the eggs. The sex of the offspring is determined by the temperature in the nest and is fixed within seven to 21 days of the start of incubation. Incubation temperatures of 30 °C (86 °F) or lower produce a clutch of females; those of 34 °C (93 °F) or higher produce entirely males. Nests constructed on leaves are hotter than those constructed on wet marsh, so

2068-469: The wetlands, they increase plant diversity and provide habitat for other animals during droughts. They are, therefore, considered an important species for maintaining ecological diversity in wetlands. Farther west, in Louisiana, heavy grazing by nutrias and muskrats is causing severe damage to coastal wetlands. Large alligators feed extensively on nutrias, and provide a vital ecological service by reducing nutria numbers. The Chinese alligator currently

2115-431: The young alligators. Alligators, much like birds, have been shown to exhibit unidirectional movement of air through their lungs. Most other amniotes are believed to exhibit bidirectional, or tidal breathing. For a tidal breathing animal, such as a mammal, air flows into and out of the lungs through branching bronchi which terminate in small dead-end chambers called alveoli . As the alveoli represent dead-ends to flow,

2162-537: Was designed to improve the flow of the St. Johns River into and out of the lake. Several other projects were also undertaken to improve the quality of the lake. The Friends of Lake Jesup was active in monitoring these projects and in bringing new areas of concern into focus. There are small businesses that operate lakeside restaurants, fish camps, and airboat tours in the vicinity of the lake. [REDACTED] Media related to Lake Jesup at Wikimedia Commons Alligators An alligator , or colloquially gator ,

2209-501: Was in his 80s and possibly the oldest alligator living in captivity. Alligators are native only to the United States and China . American alligators are found in the southeast United States : all of Florida and Louisiana ; the southern parts of Georgia , Alabama , and Mississippi ; coastal South and North Carolina ; East Texas , the southeast corner of Oklahoma , and the southern tip of Arkansas . Louisiana has

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