Part 2 Our Wild Neighbors WN Bookedition2 2007 Fin 1/31/08 11:16 AM Page 65 9 ALLIGATORS
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WN_BookEdition2_2007_fin 1/31/08 11:16 AM Page 63 Part 2 Our Wild Neighbors WN_BookEdition2_2007_fin 1/31/08 11:16 AM Page 65 9 ALLIGATORS T MIGHT SEEM surprising Ithat the Am- erican alligator was once highly endangered, given Figure 20 Alligator that the Florida Fish and Wildlife Conserva- tion Commission now receives ten thousand complaints about alligators annually (Figure 20). Once hunted nearly to the brink of ex- tinction for their skins, alligators rebounded under protective laws until now, an estimated o The low-frequency vibrations made by a male alligator just before his audible two million of these animals are living in the bellow are so powerful they can make wild today. The status they hold as threatened the water “dance” in a visual display is to help protect crocodiles, close relatives of droplets. who are truly endangered. Most people confuse alligators with croc- o Although alligators have existed odiles, even though the latter are only found unchanged for so long that they are in extreme southeastern Florida along the given the title “prehistoric,” there coast. Crocodiles can subsist in saltwater habi- is nothing primitive about these tats; alligators are better adapted for freshwa- sophisticated, complex animals. ter living. Most species of crocodiles have nar- row, “V”-shaped snouts. Alligators’ snouts are o In winter, alligators excavate “gator rounded and shovel-shaped. holes” for refuge, and the water retained by these holes helps to With their formidable size and powerful support many other aquatic animals jaws, alligators are intimidating animals to through the southern winter. encounter. However, your chances of being injured by an alligator are slim: you are far more likely to be injured while boating, water skiing, or scuba diving. Alligators, however, can be a real threat to free-roaming dogs or 65 WN_BookEdition2_2007_fin 1/31/08 11:16 AM Page 66 livestock allowed to approach the waters within range. These include fish, birds, tur- within an alligator’s territory. tles, snakes, and small- to medium-size mam- mals. They will also eat road-killed animals or other carrion available close to waterways. Classification and Range Because reptiles need external heat to aid The American alligator (Alligator mississippien- digestion, alligators are most likely to feed sis) is the largest native reptile in North Amer- when water temperatures are 70 degrees F ica. Females are generally less than nine feet and above and are unlikely to feed when in length, but males can reach sixteen feet and water is in the mid-60s or below. Alligators weigh more than five hundred pounds. Alliga- and other reptiles do not expend energy to tors live in the southeastern United States, regulate body temperature, so they can sur- ranging from east Texas on the western side of vive for months without feeding. their range to North Carolina and Florida in Sexual maturity in alligators comes more the east. The largest populations are found in as a function of size than age. Most alligators Florida, Louisiana, and southern Georgia. are capable of reproduction by the time they reach six or seven feet in length. A female may require ten to fifteen years and a male Habits eight to twelve years to reach that length. That may seem like a long time, but alligators “Alligator” comes from the Spanish el lagarto, can live more than sixty years. which means “the lizard.” The skin on an alli- Courtship rituals begin in early spring, gator’s back is armored with rows of bony and mating occurs late May through early plates called osteoderms or scutes. Alligators July. The females build large nesting mounds have an elongated, rounded snout, with nos- out of vegetation about three feet high and trils at the tip to allow breathing while most of six feet wide on banks or in marshes, where the body is submerged. Alligators have poor they bury their eggs. As the nesting materials eyesight; they do, however, have an excellent decompose, heat is produced to incubate the sense of smell. Adults are dark with pale un- eggs at the proper temperature, and the dersides, while the young have bright yellow raised mound helps protect them against stripes and blotches. flooding. The sexes of the embryos are deter- Alligators are found primarily in fresh- mined by the temperature of the nest. Males water swamps, marshes, shallow lakes and are produced at intermediate temperatures creeks, and the wetlands that surround these (90.5–91.4 degrees F), while females are pro- areas. They occasionally inhabit brackish duced at low and high nest temperatures. Fe- water. Alligators excavate burrows with their males deposit an average of thirty to forty-five tails and snouts in ponds and shallow water eggs that incubate for sixty to sixty-five days holes. The resulting silt that is pushed onto and hatch in late August or early September. the banks provides nutrients for a variety of Females stay near the nest during incu- plant life. These “gator holes” are a vital part bation to protect the eggs. Alligators are most of the wetlands ecology. territorial during mating and egg incubation Alligators are very temperature sensitive and may be aggressive toward intruders. As and require good dens to survive extreme heat soon as the eggs hatch, the female moves the or cold. Temperatures above 95 degrees Fah- young to the water, where she protects them renheit (F) or below freezing can be deadly. for a year or more. The mortality rate for Alligators are not true hibernators, but during hatchlings is around 80 percent, with eggs these extremes they become largely inactive and young susceptible to raccoons, feral hogs, while waiting for better temperatures. bears, large fish, herons and other birds, and Alligators are opportunistic feeders and even adult male alligators. generally feed at night. They will attack al- most any appropriately sized prey that comes 66 WILD NEIGHBORS WN_BookEdition2_2007_fin 1/31/08 11:16 AM Page 67 Public Health Concerns Minimizing Contact The best action you can take to protect your- Alligators do not carry any known diseases self as well as the alligators is to refrain from that can affect humans. Since alligators are feeding them. Most attacks on humans are large and sometimes dangerous, their attacks from alligators who have been fed and have can be a human safety concern. lost their natural wariness of people as a result. Do not feed them unintentionally by Problems leaving food, trash, or fish scraps on shore. Swim only by day and in designated swim- As demand for housing continues to grow, ming areas in alligator country. Since alliga- more and more wetland habitat is swallowed tors are more likely to feed at dawn, dusk, and up. Draining wetlands for development dis- nighttime, minimize your outdoor activities, places alligators and other species. The more and your pets’, during those times. human beings move into their territory, the Avoid antagonizing an alligator. Throw- greater the number of human-alligator con- ing things at or even approaching an alliga- flicts. Most complaints involve alligators in tor is inappropriate and dangerous behavior such places as garages, backyard pools, and that could provoke this powerful, surprising- water hazards on golf courses. Alligator ly swift, and potentially dangerous animal. attacks on humans are actually quite rare. Since alligators prefer easy prey, if you are Attacks on dogs are more common, probably attacked, the best response is to fight. Usually because dogs are closer in size to an alliga- an alligator will release prey that is too large tor’s natural prey. and not easily overpowered. Solutions Trapping Alligators are fairly easily caught or trapped, Tolerance but this potentially hazardous job should be left to professionals. Contact your local fish Alligators may wander somewhat, but they and game department for assistance. Trans- never stray far from fresh water. An alligator location of trapped alligators is generally not in a yard or other inappropriate place will successful, as they tend to return to their likely leave of his own accord if left alone. home range. Regrettably most problem-caus- One of the most important things a home- ing alligators are killed, so it is best to inter- owner can do in these situations is to make vene early in potential human-alligator con- sure that all pets are inside and that people, flict situations, before the animal has to be especially children, do not gather around removed. an alligator. Give him a chance to move away under his own power and be prepared to call the authorities if he does not seem Alligators as Pets willing to do so. Alligators, crocodiles, and caimans (South and Central America crocodilians) should Exclusion never be kept as pets. Do not remove any alli- A solid fence at least five feet high should ex- gator from his native habitat, as he will not clude alligators, although these animals have become “tame” and will not make a safe pet. occasionally been observed climbing fences to approach dogs or livestock. Consult with local experts to ensure that any fence is designed to keep alligators out. Alligators 67 WN_BookEdition2_2007_fin 1/31/08 11:16 AM Page 68 A Last Word Alligators and human beings coexisted peace- fully in the southeastern United States for a long time. It is only in the last fifty years or so, as people have moved farther into their native habitat (while paradoxically creating more habitat with artificial lakes), that con- flicts have increased. These awe-inspiring reptiles are an important part of their ecosys- tem. Other species use alligator nests to incu- bate their own eggs and shelter in gator holes. Alligator nesting activity helps create nutrient-rich soil and, through predation, alligators control the numbers of many species.