Crocodiles use a combination of active hunting and the more passive "sit and wait" strategy. Juveniles tend to position themselves in shallow water with all four feet on the bottom and wait until potential prey comes within striking distance of the jaws. The movement of prey is detected by the enlarged sensory pits along the sides of the jaw. The most common strategy of larger crocodiles involves an underwater approach to potential prey on the bank, in the water at the bank or in overhanging vegetation. Once a crocodile is attracted by the movement, sound and perhaps smell of potential prey, it will orient its head towards the prey, submerge (usually without a ripple), and swim underwater until it reaches the immediate vicinity of the prey. Then as the head silently emerges, if the prey is within striking distance, it will lunge with the jaws opening then slamming shut. A crocodile can lunge more than half its body length into the air or out on the bank. Once caught, small prey is usually crushed and swallowed. Larger prey is squeezed tightly until all movement stops. The largest prey evokes the full attack sequence. Once the crocodile has a grip, it will roll to throw the prey off balance so it can be dragged into deeper water and drowned. Because the stomach of the crocodile is small relative to the size of some prey taken, head shaking, thrashing and rolling is used to dismember large prey into smaller pieces for eating.