The Roaring Lion; A Close-up Look
Terri L. Soderstrom
Docent, Greater Los Angeles Zoo Association
Los Angeles, CA
Lionologists know that both male and female lions roar, almost always at night, with the male’s voice being louder and deeper. A roar starts with a sequence of long groans that end in a pattern that is distinctively the lion’s own. Lions will not waste energy roaring on a windy night, but, on a still night you can hear a lion’s roar for up to 5 miles, and it can shake a car from 30 yards away. They will roar over and over again throughout the night. Why does an inherently lazy lion expend that energy?
The lions in the Tanzania Serengeti are among the most studied wild animals in the world. George Schaller started studying them in 1966 and was followed by Craig Packer and Anne Pusey in 1979. Choosing to become a field biologist studying lions has it challenges, boredom being one of them. Lions spend most of their lives sleeping and waiting for them to cooperate in a study can be vexing. “For hours on end there was nothing. The lions slept, slept in the darkness, slept in the heat of the day. Month after month, moon after moon” (Packer, 1994, p. 93).
During their studies, Packer and Pusey tried using high quality sound systems and recorded roars that were then played back to the lions. They discovered that recorded roars elicited dramatic responses from the lions, which would enable lionologist to study animal cooperation experimentally. At this point, Packer invited his graduate student Jon Grinnell and Karen McComb from Cambridge University to come to the Serengeti and study the lion’s roar full time utilizing playback experiments (Packer, 1994). Based on the playback studies done by Grinnell and McComb over a period of two years, they have determined that lions roar for ownership, infanticide avoidance, choosing mates, and territoriality (Grinnell & McComb, 2001).
Ownership – When will a lion roar and when will he stay quiet?
The lion’s pride is made up of close group of females, usually related, with a dozen cubs of different ages and a coalition of 1 – 7 resident males who are often times unrelated. A single resident male is very unusual and a coalition of more than 7 adults has not been documented (Denis-Huot & Denis-Huot, 2003). At any given time there are more nomad lions than resident males – 1.37 nomadic males per resident males.
Nomad lions wander widely going in and out of territories while they are maturing and forming coalitions in order to evict resident lions. It would be natural to assume that nomads would roar to keep track of their coalition partners or to attract potential partners; however, Grinnell’s and McComb’s research showed that nomadic males never roar when in a resident lion’s territory until they are ready to launch a challenge for the ownership of the pride. Furthermore, resident lions will only roar when inside their own territory. To roar in a resident male’s territory will invite an attack. Even if nomadic lion hears a solitary female’s roar, he will only approach her silently (Grinnell & McComb, 2001).
When a new coalition takes over, the first job of the new resident males is to kill off the cubs. This sends the female into estrus approximately 8 months earlier than if the new residents waited for her to finish raising her cubs. This is advantageous for the male as his tenure is on average only 2 – 3 years; there is no time to waste. However, this is not advantageous to the lionesses, and they have developed counter strategies to avoid infanticide.
Female lions live and interact together, which is unusual in the cat world. Female lion sociality probably evolved to counter infanticide. Female sociality was traditionally explained by the advantages of cooperative hunting. However, studies by Scheel, Packer, and Pusey showed that group hunting is no more successful than hunting alone, but protecting their cubs in groups is much more successful than protecting solitarily. Grinnell & McComb tested whether females roaring as a group can keep potential infanticide males from approaching them. They played one female
roar and three female roars to non-resident males. They found that the non-resident males are significantly more likely to approach a single roar than a three-lion roar (Grinnell, 1997).
In a lion’s pride, it is not all up to the males to determine who will sire the cubs. It turns out that females may be good at inciting competition. A female wants the strongest and largest male coalition to be the resident males. To incite competition, a female might sneak off to mate with an outside male. The outside male then thinks he is the resident male and will perform his ownership roar, which will escalate into battle. If the new coalition wins the battle, the old coalition will be replaced. But what if the new coalition is not the victor and she gets pregnant with the outside male? It turns out that risk is minimized by a quirk in her fertility cycle. When mating with an unfamiliar male she takes three months to get pregnant – plenty of time for the coalitions to work it out (Grinnell, 1997).
Male Territoriality – If a lion roars is he ready to fight?
Since resident males are in the pride for such a short period of time, resident males must take every threat seriously. Resident males are always ready to fight to the death to defend their females and cubs. With playback experiments, Grinnell and McComb observed that a resident male will advance and be ready to escalate whenever an unknown roar is heard. However, avoiding a fight is always preferred.
Members of a resident coalition will roar in chorus. One lion will start the chorus, and then the other members will join in, usually one at a time, with the original lion often ending the roar. By creating this choir they signal an actual group size and a cooperative group atmosphere free of competition. This serves as a deterrent to aggressive nomadic lions (Grinnell, 1997).
Female Territoriality – Statistically aware?
The pride’s territory belongs to the female, who passes it down from mother to daughters. Females are defending “turf” while the males are defending their rightful ownership of the females in the pride. For female lions, their lives depend on the number of female companions they have.
Once a pride gets down to three females, it will certainly become extinct. McComb studied female territoriality and found that when she played female roars to groups of different sizes, the speed that the females came to defend their territory depended on the odds. During playback experiments, if the females were outnumbered they didn’t approach the audio speaker at all, but if they have a numeric advantage they arrive very quickly. She also discovered that if she played a female roar to a lone female that was temporarily separated from her pride mates, the lone female
would roar in response, presumably to enlist help and get her “comrades in arms” gathered together. In fact McComb did find that pride-mates responded within minutes of the roar (Packer, 1994).
On the Serengeti when night has set one can observe the quiet of the nomads, the “come hither” or “get lost” of a female roar and the “stay away from mine” of the resident males roar. This insight into the complexity and power of the lions roar reminds us of the richness and variety of the animal kingdom.
Denis-Huot, C., & Denis-Huot, M. (2003). The Art of Bing a Lion. Barnes & Noble Books.
Grinnell, J. (1997, May). The Lion’s Roar; More than just hot air. Smithsonian Zoogooer .
Grinnell, J., & McComb, K. (2001). Roaring and social communication in African lions; the limitations imposed by listeners. Animal Behavior , 93-98.
Packer, C. (1994). Into Africa. Chicago: The University of Chicago Press.