How Crocodiles Hunt
Have you ever seen a crocodile? We cannot help trembling when we see them tearing the prey apart with their sharp teeth and big mouths. Because crocodiles have excellent hunting skills, they have dominated the rivers, lagoons, swamps, and even seas for over 200 million years. The followings are three steps of crocodiles’ hunting process.
First, submerge and observe. They hide underwater, looking for the prey with only their eyes, ears, and nostrils in the surface. They have three amazing biological features. One is a unique metabolic system. When they are underwater, they can stop the blood from flowing to their lungs to reduce the consumption of oxygen. Another is that they can control the heart rate to 3 beats per minute, so they can even hide underwater for several hours. The other is their specialized eyes. They have nictitating membranes, which are transparent eyelids, acting as built-in goggles when they swim in the water, but the sight underwater is limited. However, the most powerful function is that they have extended sight and extraordinary night vision. Due to the position of their eyes, they can take in the panorama with only one gaze. This is a huge advantage while hunting because they can catch every subtle movement even in the dark. As a result, they just need to wait cunningly and patiently for their prey to come close to them.
Next, stalk and disguise. As crocodiles lock on the prey, they stealthily reposition as the target moves along the river bank. What’s more, some species of crocodiles would take initiative to lure the prey by disguising themselves. Vladimir Dinets (2013) noticed that during the spring nesting season, some crocodiles would cover their snouts with twigs and branches to attract the birds which are finding materials to build their nests. When those innocent birds are about to grab the branches, they will fall into the crocodile’s trap. Crocodiles have not only lots of patience but also scarily clever brains.
Finally, attack! Crocodiles have two ways to attack. As soon as the target comes close to them, they will pop up from the water and use their strong jaws to bite the prey, with the bite force up to 3700 pounds per square inch. Once they catch the prey, they would not release it, so the prey can hardly escape from the fate of being the dinner of them. Despite the fact that crocodiles cannot chew, they use a strategy called the “death roll”. They rotate their entire bodies to tear the prey apart when they encounter bigger animals. If you think crocodiles can only seize the animal by the water, the following news would definitely make your jaw drop. Despite having heavy bodies, crocodiles can propel their whole bodies out of the water by waving their powerful tail, and vertically spring out of the water to catch the birds or other flying animals in the air. As long as the prey is targeted, crocodiles can catch it wherever it is.
Since crocodiles usually wait passively for the prey, they are equipped with strong bodies, keen senses, and clever brains to make them succeed in every catch. That’s why they become the top predator in the world. Although it is cruel, it is also amazing to see crocodiles’ hunting process from submerging and observing, stalking and disguising to catching the prey with different strategies. So be careful about the hidden killers when you try to get water by the river!
References
Dinets, V. Crocodilians use tools for hunting, Ethology Ecology & Evolution (2013)