“Gregarious, territorial, matriarchal society, communal care, male coalitions.” Lions are the only truly social cat.
Life in Prides
The basic units of lion social organization are resident prides occupying hunting territories of a size that can sustain the pride during times of scarcity. Lion densities, home territory size and social group size vary in parallel with habitat suitability and prey abundance, generally larger in moist grasslands where game is plentiful and smaller in drier bush with fewer prey animals.
Home territories range from 20km2 in the most suitable habitats to more than 500km2. The average area of nine Serengeti prides was c. 200km2. Pride ranges and territories may overlap but each pride maintains a core area where most activities are undertaken with little interaction with other lion groups. Territories are stable except in periods of hardship. If an area becomes devoid of lions (as a result of disease for example) this will be followed by an influx of competing lions to claim the territory.
Prides can attain 40 members, however the average pride, both in Kruger NP and the Serengeti, consists of 13 members. In Kruger, the average composition of 14 prides totalling 181 lions was 1.7 adult males, 4.5 adult females, 3.8 sub-adults, and 2.8 cubs (including yearlings). Females outnumber males by a substantial margin, despite a near 50% male/female birth ratio. This is probably due to the tendency of males to be nomads, take on more dangerous game, and be killed in pride takeover attempts.
In larger prides it is rare for the whole pride to be together, but individuals or small groups, typically of three – five members will scatter throughout the prides territory for days or weeks at a time, especially in arid environments or times of prey scarcity. There is no hierarchy between females, and no particular bonding between any pride members. A pair of females will be found together no more than 25 – 50% of the time.
Presence within a pride’s territory is not a sign of membership as many lions are transient or “squatters”. Membership of a pride can only be distinguished by an amicable greeting ceremony performed between pride members. Any member without the confidence to perform the ceremony will be treated as outsider.
Lions will defend their territory against lions of the same gender, but most encounters do not result in fighting; usually one pride will skulk off under the watchful gaze of the other.
The adult females in a pride are usually related and will stay within the natal range unless there is a scarcity of food, under which instance two-year old females will be forced to leave. Each pride has an apparent maximum number of females. In Kruger NP the number of lionesses remained constant in six neighbouring prides for two-and-a half years, even though the actual membership of the prides changed. If the number falls below the capacity for the home range sub-adult immigrants may be allowed to join.
Due to the nature of a large number of females in grouped social structures, males are able to monopolize breeding, which has led to fierce competition between males and is behind the sexual dimorphism in lions, alone amongst the cats.
Males are forced to leave the natal pride at age two – three years and enter a nomadic phase until they are large enough to challenge a sitting dominant male for control of a pride, at around five – six years old. Brothers will usually stay together and form a coalition, oftentimes joined by males ousted from other prides.
In the Serengeti population, 42% of coalitions were formed with at least one unrelated male. The apparent benefits to winning and sustaining dominancy of a pride through increased strength awarded by a coalition are clear, however studies have shown that most coalitions are small, and many males stay as lone nomads. Out of 40 sightings of nomadic males in the Serengeti all but three were pairs and singles. Coalitions up to seven-strong have been recorded.
Most pride tenures last around two years, however collations of three or four males often last longer. Coalitions of more than four males are rare as these coalitions often take over more females than they can defend, resulting in fewer surviving offspring.