The Admirable Alligator (Part 2)

In Part 1, we took at look at alligator anatomy, motherhood and childhood. If that didn't make you admire alligators, Part 2 will! We're going to get into the very important role alligators play as predators and engineers. As you will see, they can be pretty scary at times, but alligators are actually very helpful to other animals - including humankind.

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More reasons to admire alligators:


Alligators know how to get the upper hand

In spite of their challenging childhood, alligators start to move up the food chain as they grow. Once they reach about 7 feet, the only creatures that can prey on them are other male alligators and humans (through hunting and habitat destruction). At this point, the alligators are now preying on all of the things that used to prey on them! If all goes well, they can live to be about 40 years old.  


Alligators are cold-blooded killers

While that may not sound very admirable, alligators do an excellent job of filling their important role at the top of the food chain - even if it does make them unpopular at times. And, they literally are cold-blooded. They don't have to waste energy maintaining a certain body temperature, so one good meal could last several days to a week. In a pinch, an alligator can go for a whole year without food. But when an alligator is on the prowl for a midnight snack, look out!


Alligator hiding among water plants near the water's edge.

Alligator hiding among water plants near the water's edge.

Alligators mostly hunt by lurking - often at night. They are aided by excellent night vision. And, in spite of their armor, alligators can feel even slight disturbances in the water, helping them detect prey in total darkness. Once they have made their menu selection, they use their powerful tails to lunge toward their prey in or near the water, grabbing it in their powerful jaws. They are able to catch things underwater without swallowing gallons of water because they have a palatal valve that prevents water from going down their throat when they open their mouth. Because the palatal valve has to open to swallow dinner, alligators cannot eat underwater, so they either have to get out of the water, or throw their head upward above the surface of the water.


This alligator's palatal valve is closed. It's a pink, fleshy flap covering the esophagus. An alligator's esophagus has to be quite large to enable it to swallow large prey whole.

This alligator's palatal valve is closed. It's a pink, fleshy flap covering the esophagus. An alligator's esophagus has to be quite large to enable it to swallow large prey whole.

In spite of having all those beautiful teeth, alligators can't chew their food. When they catch something large, they have to rip manageable size pieces off their prey by whipping their head from side to side, or by quickly rolling over in the water. Sometimes an alligator will store a larger item underwater so it can rot for a while, making it easier to rip it apart. All of this is rather inconvenient, so alligators generally prefer to catch food they can swallow whole. For this reason, humans aren't of much interest to alligators, but there have been notable exceptions to that!


This alligator has a fish that's apparently a little too big to swallow whole. It has been shaking its head from side to side to rip pieces off.

This alligator has a fish that's apparently a little too big to swallow whole. It has been shaking its head from side to side to rip pieces off.

Alligators are digestive marvels

An alligator might eat a meal that's up to 20% of its body weight in one sitting. You would think that could give him indigestion. However, alligators are able to digest just about anything, including bones, feathers and horns. That's because their digestive tract is specifically adapted for eating infrequent, large meals. For one thing, alligators swallow rocks that help their stomach "chew" the food. Also, alligators have a special valve in their heart that lets blood bypass the lungs and go straight to the stomach. This blood is full of carbon dioxide - a key ingredient in gastric acid. This enables them to produce gastric acid ten times faster than any other animal. This is important because those big meals tend to stay in the stomach for a long time, and the acid prevents the food from putrefying and making the alligator sick. Nice, huh?


This alligator has gotten a little too warm while recharging its batteries in the sunshine, so it has opened its mouth to cool off a little bit. 

This alligator has gotten a little too warm while recharging its batteries in the sunshine, so it has opened its mouth to cool off a little bit. 

Alligators like to chill out

When the South Florida weather heats up in the summer, alligators need to cool off. They can do that by opening their mouth or taking a swim. If that's not enough to get the job done, they aestivate, which is different from hibernating. They lower their metabolic rate, going into a light state of dormancy for a brief period of time in a cool, dark, moist place - often a den they dig into the bank of a lake or river. (In contrast, when hibernating, an animal goes into a deep state of dormancy in a warm place for a long period of time.)  


Alligators are engineers

Animals at the top of the food chain often play a very important role in the ecosystem in which they live. This is especially true of alligators in the Everglades, where they are considered a "keystone" species. That means they have a larger impact on the ecosystem than any other species. How? Predation, of course, which helps keep the population of its prey species in check. But alligators also make a very important engineering contribution to the Everglades ecosystem: alligator holes!


This is a big alligator hole. As the alligators pushed muck and vegetation out of the hole, a low berm would have formed around the outside edge. Trees and shrubs that can't survive in the surrounding sawgrass marsh are able to grow on this "high ground." Some alligator holes have been maintained for centuries by many generations of alligators.

This is a big alligator hole. As the alligators pushed muck and vegetation out of the hole, a low berm would have formed around the outside edge. Trees and shrubs that can't survive in the surrounding sawgrass marsh are able to grow on this "high ground." Some alligator holes have been maintained for centuries by many generations of alligators.

Through their foraging activity, alligators clear away mud and vegetation right down to the limestone bedrock to create holes that are usually 10-20 feet across, and 2-3 feet deeper than the surrounding marsh and sloughs. When the rest of the Everglades dries up during the dry season, there will still be water in the alligator holes. This enables fish, shrimp, frogs, snails and turtles to survive. In turn, this attracts water birds that prey on these creatures. Raccoons, bobcats, and other mammals come to the gator holes in search of drinking water. Of course, the alligators will eat some of these critters that are using the alligator holes, but most will owe their survival to the gators. Once the wet season arrives, everybody spreads out in the marsh and goes back to business as usual.


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Because alligators and alligator holes are so important to the Everglades ecosystem, any Everglades restoration plan needs to ensure alligators continue to thrive. It is worth noting that a healthy Everglades is required to ensure a steady supply of fresh drinking water to the Miami area, and is South Florida's first defense against rising sea levels. By supporting the Everglades ecosystem, alligators are helping humankind in South Florida in profound ways. Now there's a good reason to admire alligators!



DID YOU KNOW?


Alligators know how to keep their mouths shut

Alligators have very powerful jaws. Their jaw muscles are designed to slam shut on prey, and they are impossible to pry open. But alligators don't have much strength for opening their mouth. That's why alligator wrestlers can easily hold an alligator's mouth closed.


In the state of Florida, it is illegal to feed wild alligators

This law is for the benefit of both humans and the alligators. Feeding alligators can cause them to overcome their natural fear of humans. When this happens, they may begin to approach people looking for handouts, and even become aggressive. Nuisance alligators that become a threat to people are often trapped and killed. So, if you want to be helpful to alligators, leave them alone!


You see many signs in the Everglades warning you not to feed the alligators. Doesn't it seem like common sense alone should be enough to keep people from doing that? Yikes. Admire them, but don't feed them!

You see many signs in the Everglades warning you not to feed the alligators. Doesn't it seem like common sense alone should be enough to keep people from doing that? Yikes. Admire them, but don't feed them!

The arm you see in this photo belongs to our airboat driver on the Miccosukee reservation in the Everglades. Apparently, he didn't read the sign, but risking his arm did give us some good photo ops.

The arm you see in this photo belongs to our airboat driver on the Miccosukee reservation in the Everglades. Apparently, he didn't read the sign, but risking his arm did give us some good photo ops.


See you later, alligator!


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