A lioness is ready to have young when she is 2–3 years old. Young lions are called cubs. Cubs are born after 3 1/2 months. The cubs are born blind; their eyes do not open until they are about a week old, and cannot see well until they are about two weeks old. Lions do not have a den (home) where they would live for a long time. The lioness conceals the cubs in thick bush, gullies, or rocky outcrops. If the hiding place has been seen by other predators, then the lioness will move the cubs to a new hiding place. The cubs will be introduced to the pride at about 6 weeks old. The cubs are very vulnerable when the lioness goes out to hunt and needs to leave the cubs behind. Also, when a new male takes over a pride from another male, he usually kills all of the cubs. The cubs' mothers will then mate with the new pride male, which means that the first batch of new cubs will be his offspring. A litter of 2-6 cubs are born. Usually, only 1-2 cubs survive until introduced to the pride, at which point they are protected by the whole pride.