Monday, December 8, 2008

Lion Behaviour and Distribution

General information on lions

Distribution

Lions were once found the length of Africa and the middle east all the way to India, where a small population still remains in the Gir Forest. Currently the lion is found in savanna and plains habitat across the continent, although is now absent from north and the far south of Africa. The last large remaining populations are found in the Serengeti National Park and Selous Game Reserve, Tanzania, and Kruger National Park, South Africa. The main reason for the decline in the lions range since the nineteenth century is competion with man due to hunting and loss of habitat.

Life history

Lion gestation lasts 3 1/2 months, with typically four cubs being born blind and helpless, weighing only 1-2kg. The cubs will be born in a den, which is often situated in a kopje or dry river bed, to provide them protection for the first few months of their life when they are especially vulnerable to predation by hyenas, leopards and other lions. The cubs will stay with their mother in the den for the first 2-3 months before being introduced to the rest of the pride, which allows them some time to grow and toughen themselves up a bit before having to deal with the rough and tumble of pride life. A pride can range from two to 19 related adult females plus their offspring. During this period the mother will often leave her cubs for upto 24 hours in order to feed and socalise with the rest of the pride. When you first see a new litter of cubs they will be around three months old, but often by this stage there will only be 2 or 3 cubs surviving as there is an 85% mortality rate in the first year, with 25% of this being due to infantacide, the rest to starvation and abandonment. The risk of starvation only receeds when the cubs are able to hunt for themselves. Tlhe cubs will start to eat scraps of meat when they are first led to kills by their mothers at around 2 months, and will be fully weaned by around 8 months.

As the females in the pride tend to have a synchonous oestrous, and lots of cubs born at the same time, mums and cubs will often form large creche groups. The creche will provide protection for the cubs as they grow up as there is safety in numbers. Another advantage of having cubs of a similar age is that older cubs won't monopolise the milk when females suckle one anothers cubs. Generally mothers won't tolerate cubs other than their own suckling, but as lions spend upto 20 hours a day sleeping, cubs often take advantage of this to sneak an extra feed from a lactating female. Over the next two years the cubs are dependant on their mothers and they will learn how to hunt and form bonds with siblings and other pride members. By the time the cubs have joined the rest of the pride they will be able to observe prey movements, and will imitate hunting behaviour such as stalking and killing actions in their play. The adult females, unlike adult males, are very tolerant of cubs playing with their tails and jumping all over them, and will occassionally join them in play.
Lion Head Door Knocker

At two years old the cubs become sub-adults and the males and females take two different paths. Females tend to be recruited back into their natal pride, whereas the males are kicked out by theirparents. Males will have a nomadic existance for the next 2-3 years, roaming around in unoccupied/poor lion habitat, such as the short grass plains of the Serengeti. During this time they try to avoid trouble with resident males and will grow in size and strength and develope a full mane. This is an important period for develping strong bonds with their littermates, as the coalition they form now will decide their future sucess at having a pride of their own one day. Males unfortunate enough to be born into a cohort without any other males will often team up with other lone males to increase the size of their coalition. Coalition size can range from a single male to up to seven males, with typically three or four males in a coalition. If less than three males there is a chance they might not be related, but if more than three will be related. Sometimes young females will leave the pride with their brothers, particularly if there has been a pride takeover or the pride has become very large. These females may set up a new terrirory adjacent to their natal territory or could return to the natal pride when they reach sexual maturity at 4 years old. By the time an adult female is fully grown she will weigh 126kg and stand at 110cm.

Adult males become sexually mature at five years and will weigh 198 kg and stand at 120cm. and this is the time when a coalition of males attempts a pride takeover. This is a bloody and brutal affair, with males often fighting to the death. Incoming males will kill or chase away all the cubs and sub-adults sired by the previous coalition. Cubs less than 9 months are generally killed, and cubs older than that are able to run away and are expelled from the pride, but will often starve as they are unable to fend for themselves. Female lions will vigorously defend their cubs from incoming males and occasionally do succeed in chasing away single males. It has also been observed that females will leave the pride with their cubs to avoid the infanticide of their cubs by new males. Male tenure of a pride is fairly short, only 2-3 years, which is just enough time to rear one cohort of cubs before the next coalition will take over the pride. The reason for the males committing infanticide is that due to their short tenure of the pride they don't have time to spend raising another males cubs. When a female loses her cubs, she will come back into eostrus fairly within weeks. However it has been observed that after a takeover females will mate repeatedly with the new males without ovulating. This allows the females not only to bond to the new males, but also to delay reproduction until the strongest coalition in the area vieing for the pride has made a successful challenge.

When a female is in oestrus she will mate roughly every 15 minutes for four days. Before a female comes into oestrus she will be mate guarded by the male in the coalition who gets to her first. There is no agression between males at this time and there is a 'first come, first served' approach. Within the male coalition there will be a dominance hirarchy and the most dominant individual will generally get to the female first at the peak of her oestrus. The next dominant male will then mate with her afterwards, but still has a chance of sireing cubs. As there is often synchonous eostrus within a pride, less dominant males will have the opportunity to mate as several females will be in heat at the same time and females will have a degree of mate choice at this time.

Hunting

Lions are oportunistic hunters and will readily scavenge kills from other predators, such as hyenas and cheetahs, and will follow vultures to a carcass. Although lions do the majority of their hunting at night, they will hunt in the midday sun if an opportunity presents itself. Lions favourite prey is wildebeest and zebra, but in the dry season they will take warthog and buffalo. Females do the majority of the hunting due to being smaller, faster and more agile than the males. Also they don't have a big mane to give them away when stalking prey! However, males will often help to bring down larger prey such as buffalo and giraffe. A lion hunt will be more successful if several individuals cooperate to bring down an animal, but it has been found that a lion will get more food over time when hunting on their own even though the percentage of successful hunts is much lower. After a kill it is each lion for himself around the carcass, with smaller, weaker animals losing out. As there is no hierarchy in lions they often get into scrapes round the kill which results in injuries such as ripped ears, missing eyes and missing tail tufts. A lion can eat up to 1/4 of its body weight in one sitting, although they will normally consume between 5-7kg per day.

Territories

Lion territories range in size from 20km2 to 400km2 depending on habitat type. Territories generally larger in poor habitat, as the lions have to range wider to find food and water. In woodland habitat, which is good for lions, territory size is much smaller as there is a greater concentration of resources. Both males and females actively defend their territories from other lions and patrol territory boundaries regularly scent marking by either spraying urine against trees or bushes and scraping the ground, along with head rubbing on trees and rocks. Roaring also has a territorial advertisement function, with bouts of roaring often occurring at dawn or dusk. Roaring also helps pride members locate each other and reinforce social bonds. Whilst patrolling their territory if lions encounter non-pride members they will drive them away and often get into fights. They will also chase and kill other carnivores, such as cheetahs, leopard and hyenas they find in their territories.

Visit Wild Things Tanzania Safaris for more information on visiting the Lions in the Serengeti.

Noble Lion Sculpture


About the Author
Kirsten Skinner is a former research scientist who works with Wild Things Safaris Ltd Wild Things