There are 23 species of crocodilian spanning eight genera. Crocodilians include crocodiles, alligators, caimans, and gharials. Like all reptiles, crocodiles are cold blooded. Here, we’ll discover the fascinating way that crocodiles’ cold bloodedness allows them to go over a year without eating—if they have to. Along the way, we’ll learn about all the incredible things that make crocodiles some of the greatest survivors on the planet. Read on to learn more about crocodiles, and how they can go a year without eating!
Crocodiles: The Facts
Crocodiles are some of the most impressive animals on Earth. They’ve been around, with little change, for about 80 million years. That means that, unchanged, they’ve outlived just about every other creature on the planet, including the dinosaurs. Crocodiles can go a year without eating, but they can also eat a massive quantity of food in a single sitting.
Let’s take a look at what makes crocs so special.
Crocodilians live on every continent except Antarctica and Europe. The largest species is the saltwater crocodile of southeast Asia and northern Australia. North America is home to the famous American alligator, as well as a few American crocodiles. Overall, there are around 23 species of crocodile, depending on how you group them. The smallest species is the dwarf crocodile of western Africa.
Size and Appearance
No matter their species, all crocodiles are recognizable as crocs. They have scaly, reptilians bodies with short legs and long tails. Their heads are long, with generally narrow jaws filled with 60-110 teeth. Crocodiles range in color from dark green to tan with brown markings. Both their eyes and noses are located on top of their head so that they can remain almost entirely submerged in the water.
The largest crocodiles (saltwater crocodiles) grow up to 23 feet long. The smallest crocs, dwarf crocodiles, grow to an average adult length of just five feet. No matter their size, all adult crocodiles are formable predators, but only the largest crocodiles can go a year without eating.
Young crocodiles start out life as miniature versions of their parents. Because of their size, they’re highly vulnerable to attacks from larger crocs, birds, predatory fish, and even toads. For the first few years of life, crocodiles are restricted to eating small prey, like rodents, frogs, salamanders, insects, and fish.
Large adult crocodiles, which may measure over 15 feet long, are apex predators with no natural threats. They’re capable of eating deer, wildebeest, zebras, buffalo, monkeys, wild boar, fish, turtles, and frogs. Indeed, there is little a crocodile won’t eat. In the case of the invasive, poisonous cane toad in Australia, this can actually lead to the croc’s death.
How Often Do Crocodiles Eat, Normally?
Crocodiles are the largest reptiles on the planet, and, they can eat up to half their body weight in a single sitting. How often a crocodile eats depends on how big their meals are. It’s true that crocodiles can go a year without eating, or more. But, if they can help it, they don’t go that long in between meals. Most crocs eat every 3-10 days, depending on the size of their meals.
Crocodiles have a mouthful of fearsome teeth, but, they don’t use these teeth to chew. Instead, crocodile teeth are used only for grabbing and tearing apart prey. When it actually comes time to eat, crocs either tear off and swallow a large chunk, or, if the prey is small enough, swallow it whole.
How Did Crocodiles Outlive Dinosaurs?
Like all reptiles, crocodiles have cold blood. They’re also especially well suited for surviving in a wide array of environments. Crocodiles are rightly feared and respected—they’re some of the most successful predators that have ever lived. A combination of all their strengths, including their cold-bloodedness, is what allowed them to survive when all dinosaurs and other large animals died. Today, their greatest threat comes from humans and human activity.
Let’s learn about how their cold blood allows crocodiles to go a year without eating!
Surviving Off Their Own Tissue
Unlike warm-blooded animals, like humans, moose, and bats, crocodiles have cold blood. They’re ectotherms, like rattlesnakes and monitor lizards, who rely on the heat of the sun to warm them. Unlike warm-blooded animals, crocodiles do not have to use the energy they get from food to stay warm. This frees up a tremendous amount of energy for other uses, and allows crocodiles to go a year without eating if they need to. Crocodiles use 100% of the energy they get from food to run their bodies. Without having to worry about keeping themselves warm, crocodiles can survive where many other animals die.
But, having cold blood isn’t the only thing that allows crocodiles to go a year without eating. Crocs store fat in their tails. When times get hard, and food gets scarce, they can actually feed their bodies with this stored fat. So, when there is no food, crocodiles can survive off their own body tissue.
Are Crocodiles Endangered?
Today, there are 12 species of crocodile in danger of extinction. Some of their main threats come from hunting (for their skins and meat), habitat loss and fragmentation, pollution, and loss of prey species due to human activity.
There are currently five species of crocodile listed as Critically Endangered: the African slender-snouted crocodile, the Cuban crocodile, the Philippine crocodile, the Siamese crocodile, and the Orinoco crocodile. Some of the most famous crocodiles, the Nile and saltwater crocodile, are not currently at risk of extinction.
Crocodile conservation efforts typically start with enacting protections over wild populations of endangered crocs. Today, conservation groups work to protect the few remaining members of critically endangered species.
For some species, like the mugger crocodile, conservationists breed clutches of babies in captivity, and release them into the wild when they’re able to fend for themselves. Habitat and prey protection measures are also key to crocodile conservation. Unfortunately, for some crocodilians, like gharials, populations are still declining.
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