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National Geographic: Realm of the Alligator (1987)
This is a place of unseen danger
and subtle beauty. It is a mysterious swamp called "Okefenokee"... the realm of the Alligator. Okefenokee... a forbidding place once thought to harbor deadly diseases. It sheltered fugitives and inspired fear and superstition. Today Okefenokee Swamp is a well-know wildlife refuge. But even for people like biologist-photographer. Dr. John Paling, it is not entirely welcoming. "Whenever I go back to Okefenokee now, I've got mixed feelings about it". From the air when you go across it, it looks just so beautiful and so serene and so natural and so appealing. And yet it can be a place of such contrasts that it seems almost as if man was never intended to be there for long. Okefenokee Swamp is a A mosaic of islands, forest, marshes, and open water. It's famed for its alligators and as the home of Pogo, The comic-strip possum. Although it overlaps the Florida state line, most of Okefenokee lies in southeastern Georgia. Okefenokee's population of Seminole Indians was driven out in the 1830s. It was soon infiltrated by white settlers called "swampers." By the 1930s the swampers were well established here, Showing off alligator nests and eggs for visiting photographers. The swampers were a breed apart. Many had few needs or interests outside Okefenokee. Those who knew them admired their simplicity and self-reliance. Soon after the turn of the century, virgin stands of cypress brought an invasion to the swamp. This and earlier schemes to build a ship canal through the swamp and even to drain it threatened to destroy Okefenokee. But much of Okefenokee's prime timber was cleared in less than 20 years. Soon the swampers were alone again. In 1937, Okefenokee was declared a national wildlife refuge. The human residents would eventually leave. One old-timer said, we have the swamp and that's good. But the swampers are all gone. It's just a shame we can't have both. More than fifty years after they were abandoned, relics of the old logging camps still can be found. Now deep in regrowing forest, they're objects of curiosity for biologists like Kent Vliet and John Paling. This is an old train. Oh, this is? The engine was up front... and there would be water in this old cylinder. After working here for several seasons Paling, born in England, has become intimately familiar with this Georgia swamp. And there's something even more dramatic over here. Come and have a guess sat this. What do you make of this? That's some sort of a chassis. Right. Is that what they carried the logs on? Nope. Try again. Don't forget we're on an island in the middle of Okefenokee, so try again. Some sort of swamp buggy or something like that? It's a car. They had three cars on the island. Really? That's a heavy... Heavy duty, isn't it? Heavy chassis... But look how well the metal's been preserved. Yeah. And there's another thing to pick out too. You see why it's so good? It's British Right-hand drive. It's Durant car that they brought over on the trains for three people. Is that right? Yeah. There were three cars that would chug up and down. And this thing is preserved so well. Many cars that are ten years old don't have a chassis as good as that. that's a very heavy chassis. Right. I think it was just to take people up and down. There's a big turpentine still at the end of the island too. And there was a cinema, there was a barber ship. All gone now. It's amazing. Yep. Trains. When the logging company finished up business, they just tried to get all the people off when the National Parks Fish and Wildlife took it in 1937. Although parts of Okefenokee can be traversed on foot, it is better explored by boat. The waters of Okefenokee look like polished ebony, dark but highly reflective. It is a landscape of mirrors, fascinating and surreal. Kent Vliet is from the University of Florida. He's an expert on Okefenokee's most famous resident, the alligator. You know there's one right in front of us, John? Yep. I can see that one. The ability to "call" alligators by making certain curious sounds is a valuable skill for inquisitive biologists. It's coming. Whoa, hey. Do they have binocular vision? Can they see three dimensions? Only a little small fraction of their total visual field just in front of their nose is binocular Is he coming too close? No, he's fine. Wow. Why do they have the yellow ring around their eyes? Is there a function that's known for that? A number of aquatic animals have coloration around the eye like that hippopotamuses do. It might have something to do with magnifying the light going into the eye Sort of the reverse of a football player putting black grease under the eye. To make you see better in fact. He's going to go down. There he goes. How long will they stay under water? They can stay under a good long time. When they're resting in the afternoon, they go down for at least 15 minutes. He's up again, look. Yeah, there it is. In the wintertime they may stay down for days. Nobody knows. For days and days? You mean they really... You mean they hibernate? Well, yeah, in the sense it is a hibernation. Their metabolism slows down so much when they're that cold that they just require almost no oxygen. And they don't eat, obviously, if they... No, they don't eat for several months during the winter. I should think the average member of the public that comes to Okefenokee and sees an alligator thinks they have really arrived in prehistory Back in the Age of the Reptiles. The study of alligator social behavior has occupied Kent Vliet for several years. At his laboratory in Gainesville, Florida, he works with a wealth of accumulated data. We've learned that alligator behavior is very, very complex. It's much more complex and much more sophisticated than the behavior of other reptiles that have been studied. And so our dealings with alligator behavior have been to try to document the types of behaviors they show and analyze these, Not only in simple terms of alligator behavior, but as they might represent the primitive beginnings from which the more complex behaviors of birds and mammals have evolved. Most of Kent's observations have been made at the St. Augustine Alligator Farm. Several hundred alligators are on display here for the enlightenment of tourists. The farm affords easy access to an otherwise elusive animal. before that just to see if the place would work out. Are there many differences between these gator-farm alligators and the ones you get in the wild? Well, captive animals look a lot different from wild animals. The most noticeable difference... Is that the head of a captive animal is much broader. You don't have this beautifully elongated snout. That's because captive animals spend so much time on land basking, and at least in old animals like these the head weighs so much that is just tends to flatten itself out over the years. It spreads out and becomes much broader Is that what squeezes the teeth out too Yeah... because they're all showing very obviously here? They're very toothy animals Also all the scales on their back are worn down... much more so than a wild animal would be. And that's just because these animals live in very high densities on farms, and they crawl over each other. they just kind of buff each other down all the time. Since 1981 Kent Vliet has made a detailed study of alligator behavior in the mating season from April into June. But Kent was not happy with his original vantage point. It was secure, but didn't provide an accurate water-level view. He decided to enter the lake a procedure not without certain risks. It is possible, when you're in the lake that a big male will decide he doesn't want you there and actually come up and try to get you out of his territory. We've had very few problems when I was swimming in the lake, but there's always the potential for an alligator getting hold of you and doing some real damage. Kent has found that alligators here at the farm are fairly harmless especially during mating season. And, to increase his knowledge, he puts this opinion to a highly meaningful test. We learned early on in our research that we needed to get off the boardwalks and go down and look at alligators at an alligator's eye level. Alligators communicate to each other visually by the way they hold their bodies out of the water. And we got down into the water to better understand how alligators are talking to each other in a visual sense. Kent has taken a lot of kidding about being up to his eyebrows in alligators and "seeing eye to eye" with his study subjects. But he feels that because he can understand an alligator's body language he can ward off trouble before it becomes a real threat. I look for animals that are obviously directing themselves toward me as aggressive animals. The way they tilt their head and how high they hold their body out of the water are all indications if they're being aggressive or not. Not all the animals that come towards me are aggressive. Many are curious, but I still have to treat them all about the same. I can't let them get too close to me. I carry a large, about five-foot-long cypress pole with me, And if an animal does get too close, I just nudge it away and try to keep it out of strike range. The meaning, if any, of an alligator's impressive yawn is not understood; But other behavior like this head-slapping display has been deciphered. It is an assertive gesture, advertising an alligator's social position. In courtship season the alligators stage "bellowing choruses" almost daily. Both sexes bellow, but they make somewhat different sounds. Just before a male bellows, he produces subsonic signals that make the water around him dance. In the wild these signals may dram females from a great distance. Courtship is a quiet and oddly tender process that Kent has sometimes been able to witness at close quarters. Courtship is usually initiated by one animal swimming slowly up to another. And this is a very important stage of courtship because they have to communicate to each animal that they have non-aggressive intentions. And secondly, they go into a period of touching one another along the face and neck. And they really orient to each other's head and neck. in the third phase of courtship these touching behaviors become more exaggerated and the animals start pressing each other down under water. And these are real tests of strength between the two animals. And these will be accentuated until one animal is capable of pressing the other under water and ultimately circle around and mount on that animal and begin riding it around and ultimately roll over to one side and attempt to mate with that animal. However they behave, alligators have reproduced quite successfully in Okefenokee. Here, until the 1970s they were badly hit by poachers. Now, stiff laws protect a population that has grown to about 12,000. In summer, bubbling gases are like the heartbeat of Okefenokee. Beneath the dark waters is a thick layer of decomposing vegetation called peat. The gases it creates sometimes lift large patches of peat to float on the surface. Old-timers called this a 'blow-up'. Over time, the floating mats of peat are covered with vegetation. Some sink again, but others become floating islands and eventually support bushes and even trees. Ultimately, the trees take root and new land is created small wooded islands known locally as houses. Okefenokee is an Indian word that means 'land of the trembling earth' John Paling shows how fitting the name is when he lands on a young floating island. I actually enjoy walking on "trembling earth", if I admit it. It's one of these strange experiences like walking on a bowl of jelly. The waters of Okefenokee are highly acid, about as acidic as strong tea and much the same color. Conditions favor the growth of insect-eating plants that are found here in great variety. This pitcher plant lures insects to its hollow tubular leaf with nectar. Once inside, few insects escape. They're fooled by light from the translucent windows that line the back of the tube. They exhaust themselves trying to get out. Eventually the insects fall to the bottom of the tube. There they are dissolved by acid secretions and the plant absorbs them. Another deadly attraction is the sundew Its leaves are adorned with brightly colored stalks tipped with shiny droplets apparently a sweet meal for passing insects. But hungry insects soon become entangled. Escape is impossible when the plant finally closes to digest its victim. Along the edges of islands and in shallow marshes insects are snared in such deadly traps. When it's all over, there will be nothing left of them except their indigestible husks. As night falls Okefenokee's gloom and its grandeur deepen. One hundred million years ago the alligator's ancestors thrived in prehistoric swamps. As far as we know, they looked much as they do today. The eyes of the alligator are highly reflective. They shine with an eerie glow in the night. John Paling and Kent Vliet conduct a nighttime search for baby alligators Disturbing alligators here in the refuge is strictly outlawed. Even scientists like Vliet need special permission just to touch one. Let's cut off the engine for a minute and get some peace. Okay. Wow! That makes a difference, doesn't it? Let's pole from here. It's beautiful in here. Nice and quiet without that outboard. Sure thing. Do you see any gators yet, or not? I haven't seen any in this small stretch here. I'll just flash the light around there Is that one over there? Yeah. That's one back in the water lilies. Let's try and get a bit closer to it, can we? I'll pole some more if you'll keep paddling on that side. Unlike the closely related crocodile, alligators rarely attack man. There are only about a half dozen fatalities on record, and there has never been a serious incident in the Okefenokee Refuge. Even so, there's a certain tension whenever they're about. Do you see one? I'll keep going. Say when. Okay, Just a little closer. You got one? The captured baby gives a continuous cry of alarm. John and Kent work quickly. They want to minimize stress on the baby and avoid trouble with its mother who might be nearby. Forty-two-and-a-half centimeters. Forty-two? Uh huh. Forty-two. Good. What's it reading? It's just at 200 grams. Watch it, watch it, watch it, watch it My god! She's really cruising. Is it the call of the baby? Yeah. The baby's just continually calling. Well, hang on. Her jaws are open a bit Her teeth are showing. Kent, are you sure it's okay? I don't think it's a good idea to stay here. Do you want to put the baby back, or what? Probably what I should do is just tap her on the nose and see if it scares her. They are often a little more brave at night than they are in the daytime. Watch! She's coming, Kent. Boy, she really concentrates on that... She just localizes right on the distress call. I think I had better push her off. Are you sure? She's a little too close. This is not safe. She's not safe? No. How about just putting the baby back? Don't you think that's the best idea? Yeah. We're definitely at a disadvantage. So Kent builds a record of alligator growth in different areas. Females grow to an average of seven to eight feet, While males may be up to 14 feet and weigh 850 pounds. Not all of Okefenokee's wonders are found in the marshes. John Paling explores a pine forest in search of the red-cockaded woodpecker. The birds are endangered and difficult to find. They live in groups of three or more, and each of these so-called "clans" requires about 200 acres of home range This small woodpecker, only seven inches in length, has become famous for its finicky habits. It will only make holes in old pine trees that are usually infected by a certain disease red heart fungus. The fungus softens the tree's inner core, making the woodpecker's work easy. When a clan of woodpeckers finds trees that suit them exactly, They may remain here for life. The woodpecker's keep busy, however, carrying out a fascinating scheme for survival. They constantly make fresh holes in the trees, causing them to exude a thick coating of resin. It's a sharp and smelly substance, the main ingredient of turpentine. The woodpecker's nest hole is surrounded be resin. And it's always located on the western side of the trunk where the heat of the sun will help keep the resin moist and fresh. The reason for all this only becomes clear with the appearance of a predator like this corn snake. Sometimes this snake can be an amazing tree climber. It can climb straight up and reach bird nests 30 feet above the ground. Eggs or baby birds inside the woodpecker's nest are seemingly easy prey. But now the resin comes into play. To the snake it's a powerful irritant. Frequently is stops the snake entirely Even if the snake persists, it still tries to avoid contact with the resin. Often the snake ends up retreating the hard way. Such moments of threat and drama frequently interrupt the tranquility of Okefenokee. The predator in one situation can become prey in the next. A baby alligator in pursuit of a diving katydid. Hiding underwater, the katydid is safe temporarily. But after two minutes or so, it must come up for air. It's midsummer. John Paling and Kent Vliet search for alligator nests. At this time of year dozens of nests are concealed in the swamp. The best way to find one is to look for the trail the female alligator has made when coming and going from the nest. They should be pretty clear. If they're used often like a trail to a nest is, they're pretty obvious. This looks like one right here. Left? Right by these yellow flowers in this clump here. Let's shove the nose of the boat in here. Yeah, this is one. Oh, I can see it. Yeah. It does look like it's used pretty frequently too. That one looks really packed down. I think it's probably one leading to a nest. Alligator trails form a network of natural pathways through the swamp. They were often followed by early explorers. But there's a drawback. Alligators like to lie submerged along the trails. It's all to easy to step on one. In the nesting season the female alligator is on the defensive. She herself has nothing to fear, but her eggs are highly vulnerable. Scavengers often attack the nest. Wait a minute. Here's the nest. It's been attacked, hasn't it? No, I think they've been eaten. Something's gotten into the nest and eaten the eggs. Oh. What would have eaten these then? Probably either raccoons or black bears Black bears eat a lot of alligator nests here. But I mean raccoons and bears wouldn't swim and wade through this stuff? Well, there could be one living in this island, or he may have moved from island to island. It's hard to say if it was a black bear or a raccoon though. Sometimes black bears will pick off the end of an egg and just eat the insides out of it. I don't know how they do it. They may just use a claw and just pop the top off and eat it. This is sort of like an island. How does the mother make it? I think this nest is either sunk from its own weight after she built it or the water level in the swamp has risen some. These things just scrape up all the dirt and vegetation around them. You see there's peat in here and a lot of plant matter that holds it together. And also the rotting plant matter heats the eggs. It creates heat as it rots, and it actually keeps the eggs warmer than they would be just with the sun on them. Could she still be around now these have been eaten? I think she probably came back and realized that it had been disturbed and just lost interest and left. Let's find another one then. Okay. That's really too bad. Often the female alligator is not far from the nest. And when she discovers an intruder, she can be highly aggressive. John Paling once faced such a confrontation unexpectedly when filming a nest. This was, in Paling's understated words a moment "of surprise and serious concern". It ended only when he backed off, leaving the nest to its rightful owner The fierce protection given the nest plays a vital part in the life of the redbelly turtle. The female turtle tries to lay her eggs in the alligator's nest. If she succeeds, the mother alligator will unwittingly stand guard over the turtle eggs as well as her own. Risking attack, the turtle invades the nest and lays her eggs taking advantage of the warmth and moisture. Leaving her eggs behind, the turtle tries to get away. It's just as risky as getting in. Most adult turtles in Okefenokee bear the marks of encounters like this. Often they are not harmed. It's as if alligators recognize the turtle after one futile bite. Finding it hard to crack, they then leave it alone. The female turtle has done her part. She leaves her eggs in the alligator's protection and will not return. For otters, turtles are handy and long-suffering playthings. Otters are perhaps the most entertaining inhabitants of Okefenokee And playfulness is believed to be one strong indication of animal intelligence. Violent thunderstorms often rake Okefenokee in summer. And during a dry period lightning can set the swamp ablaze. Peat, when dry, is flammable. It can burn slowly and steadily for months at a time. So fire eats away the land in Okefenokee. Scientists think such fires may serve to revitalize the swamp, creating hollows where new ponds and lakes form when the drought ends. Recovery after a fire is swift. Soon Okefenokee is once again resplendent with vibrant color. By late summer the baby alligators are ready to hatch. It has taken about nine weeks for the eggs to incubate. A chorus of cries from the nest brings the mother alligator to assist her young. The baby turtles may also be hatching at the same time. The alligator baby. Its cries have been loud enough to be heard even before the egg has broken open. Interestingly enough, the sex of baby alligators is determined by the temperature surrounding the eggs Above 90 degrees Fahrenheit only males develop. Below 87 degrees there are only females. No one yet knows precisely how this serves the alligator's survival. The mother alligator tries to seize the young in her mouth and carry them away. The baby turtles aren't so fortunate. In all the confusion they're on their own. With ponderous care, the mother alligator carries her young away to water one by one. The baby turtles seem to know instinctively to lie low when the mother alligator is near. When the baby turtles make a break for it, they head unerringly for the nearest water. When all this is over, a new generation of both turtles and alligators begins life in Okefenokee. In 1960 a dam was built in the wildlife refuge on the Suwannee River that could change Okefenokee forever. By holding water in the swamp, the dam is intended to prevent fires and loss of timber in nearby forests. But it could also upset the balance of fire and regeneration that makes the makes the swamp what it is. Experts disagree, and it could be decades before the full impact is known. In the realm of the alligator, meanwhile, life continues according to an ancient pattern. At this age the young alligators are vulnerable to many predators. They will remain in their mother's protection for several months before going off on their own. So the alligator has survived on earth long before the time of man. And with sufficient human knowledge and concern, the alligator will remain an ancient and durable survivor of the distant past. |
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