Lions spend more time asleep than any other animal in Africa. Are lions as lazy as they seem?
First, unlike “cursorial predators” such as wild dogs and hyenas that actively seek out prey then chase them down, lions are “ambush predators” that lie in wait at spots where prey are most likely to pass. Thus lions are inherently more patient than other species.
Second, lions are more heavily built than other carnivores. They have remarkable acceleration and are able to wrestle down powerful prey such as zebra and buffalo. With all that muscle, they generate an enormous amount of metabolic heat—even just walking across an open plain can leave them panting. Thus lions have a greater need to stay cool.
Third, hunting success is low and scavenging is unpredictable, so lions may only eat once every two or three days. Lions have distensible stomachs that can hold large quantities and resting is a good way to make each meal last longer—which may be another way of saying that laziness is part of their behavioral profile.
Lions mostly climb trees to avoid swarms of biting flies or herds of angry Cape buffalo, though they sometimes seek higher ground for a better view, a cool breeze or a dry perch in wet weather. Lions climb trees everywhere in Africa, though they spend more time aloft in Lake Manyara National Park because of its plentiful buffalo and tsetse flies. Young lions are more likely to climb trees than adults, though mothers may occasionally go upstairs to take a break from the demands of nursing their cubs.
Lions only rarely venture into the water.These lions discovered a drowned wildebeest, and one female dragged it to a small island. A mother encouraged her small cubs to join the feast, but her cubs were initially reluctant before finally taking the plunge. Note how the mother follows as the cubs swim back to shore, ready to intercede if anything goes wrong.
Lions live in warm climates and have to cope with the heat. Lions mostly thermoregulate by simple heat exchange across the skin barrier, but will start panting after exertion, eating a large meal or exposure to direct sunlight. Thus they usually rest in the shade and shift position throughout the day to avoid direct sunlight. In open areas, one lion may try to rest in the shade of another or even in the shade of a parked vehicle. They further avoid heat stress by being active mostly at night, resting on top of kopjes or up trees to take advantage of cool breezes, and lying on their back to expose their thin-skinned stomachs. Licking their forelimbs may also serve a thermoregulatory function—forelimbs are highly vascular and licking may help cool the blood.
Lions usually roar between dusk and dawn. They roar to stay in touch with companions and to advertise their location and strength to rivals. Lions are sensitive to numbers, so they are able to discriminate the roars of large groups from those of small groups. They can also distinguish the roars of companions from those of strangers.
Cubs play with anything that arouses their interest, including twigs, sticks and their mothers’ tails.Cubs sometimes try to play with adults but they most often play with each other. Much of their playing imitates behaviors shown by adults, including stalking and fighting. The frequency of play is a good indicator of a cub’s health and nutrition: starving cubs are lethargic, whereas thriving cubs may play for hours in a day.
One of the ways lions define their territory is by marking. Males mark by spraying a combination of urine and scent from glands at the base of their tails. They mark trees and bushes, and scrape the ground with their hind feet while urinating. Like many other mammals, lions have a specialized vomeronasal organ for detecting scent. Lions exhibit a facial expression called “flehmen”—characterized by an open mouth, a wrinkled nose and an uplifted chin—when investigating scent marks or the reproductive state of females.
Lions face few threats from other species in their natural habitats, although buffalo will occasionally kill adult lions and sometimes trample cubs. Lions will also avoid adult elephants and are known to have died while trying to attack adult rhino, hippos and crocodiles. Hyenas will occasionally attack adult lions, especially if they are sick or wounded, and hyenas and leopards will both kill lion cubs.
However, the greatest threat to lions comes from people. Some African tribes have long considered lion hunting as an important ritual, and most lions quickly retreat from people on foot. However, as human populations grow outside the predicted areas, natural prey populations continue to decline, forcing lions to feed on livestock, which in turn provokes efforts to eradicate lions as problem animals.