(Featured image: David Bygott)

Outside the house a prowling hyena whooped mournfully, waking me from my reverie. The fire which, last time I noticed, had been burning merrily away in the fireplace, was now.a bed of glowing coals. The short wave radio, having wandered off frequency, was whining and crackling with static. The feeble, slowly pulsating light from the Petromax lantern showed that it needed pumping. Again, the hyena whooped, but farther away this time. I looked at my watch and realized the lateness of the hour . . .

Buffaloes by My Bedroom: Tales of Tanganyika

Many years later, when I think about my nights at Ngorongoro, whether in the Crater Highlands, on the floor of Ngorongoro Crater, or somewhere on the Serengeti Plains, the first thing that comes to mind is the querulous oooo-WHUP (I am here) of a prowling spotted hyena.

At the time I gave this little thought. But now, having investigated the matter, I know it was because the spotted hyena is not only Africa’s most abundant large carnivore, but also mostly hunts at night.

Something I did know, however, even then, was that the spotted hyena had an image problem. Less than handsome (although its small black cubs are cute), it has long been regarded as a skulking, slinking, nocturnal, weird-sounding, odd-looking, unclean scavenger too cowardly to prey on any but the weak and young. Furthermore, its role in disposing of human corpses encouraged the feeling that the animal is something of a living mausoleum. (Many East African tribes placed their dead, and in some cases, near-dead, in the bush for just this purpose.) Thus, it’s not surprising that the spotted hyena, whose behavior sometimes seems to verge on the demonic, also is associated with death and witchcraft. Consequently, it plays a more important role in African witchcraft than any other animal. (https://en.wikipedia.org/wiki/Cultural_depictions_of_spotted_hyenas#:~:text=In%20the%20culture%20of%20the,branded%20with%20an%20invisible%20mark.)  

That said, any spotted hyenas worried about their poor fan base can take heart from the fact that scientific research is casting them in a more positive light. Two attributes stand out: (a) high intelligence, and (b) speed and efficiency in utilizing prey carcasses. Together, these traits have made the spotted hyena a very successful carnivore. Details follow.

But first, two interesting spotted hyena facts.

Spotted hyenas look like dogs but are taxonomically more closely related to cats (most closely to genets and mongooses).

Also interesting, and rather strange, is that males and females look so alike (females have a pseudopenis and false scrotum), that spotted hyenas were long thought to be hermaphrodites.

Now, down to business:

Contrary to their reputation, spotted hyenas are highly intelligent, capable of outsmarting chimpanzees in laboratory problem-solving tests. Some everyday examples of this intelligence include (a) exceedingly cunning and suspicious behavior after escaping from traps, (b) use of deceptive behavior, and (c) an ability to plan for hunts of certain prey species in advance.

Regarding (b) and (c) above, Hans Kruuk, who studied spotted hyenas in Ngorongoro Crater and the Serengeti in the 1960’s, once observed a spotted hyena which upon finding a carcass, sounded the alarm call to keep other hyenas away, allowing it to keep the carcass for itself (Spotted hyena mothers sometimes show similar behavior by sounding alarm calls when other hyenas attempt ro kill their cubs). Hans also could often tell, from their behavior, when a group of hyenas had decided to hunt zebras, even when none were in sight and other prey were more easily available.

Other examples of spotted hyena intelligence occur throughout this report.

Complex behaviors reflect high intelligence, and spotted hyena behavior is the most complex of all African carnivores. An aspect to this is a high degree of behavioral flexibility. For instance, hyenas don’t always stick together, They may act communally, as when hunting dangerous prey, and defending clan territories, or individualistically (and highly competitively) as when caring for their young, foraging, and hunting smaller prey. This allows the species to exploit many different resources efficiently.

Females rule. Larger than males (unusual in mammals), they take the lead in territorial marking exercises, group hunts, and battles with other packs. Females also remain in the clan / pack while males emigrate (at about two years of age). Males not only defer to females, but also play no parental role, and are often not even allowed near the otherwise communal dens, Less closely knit than wild dogs, spotted hyenas more often forage and hunt alone.

Complex behavior requires good communication. Spotted hyenas are excellent communicators. This is because every individual is, to another hyena, a potential competitor (even dangerous enemy) or collaborator, which makes the signaling of moods and intentions very important. Thus, the spotted hyena has an enormous array of calls (whoops, moans, grunts, giggles, whines, yells, growls), expressions, postures, and attitudes. This can lead to a massive amount of noise when they compete with one another over a carcass. Consequently,the spotted hyena is one of Africa’s noisiest animals.

(Check out https://www.youtube.com/watch?v=kNsWowelWbo.) for spotted hyena calls.)

Highly gregarious, the spotted hyena is the most social of all carnivore species, with the largest social groups. For instance, a spotted hyena clan may comprise 35 to 80 adults. (In contrast, the largest recorded pride of lions, the other major social large carnivore, is 30 animals, including cubs.)

Social group size, however, varies with the availability of food, as does the size of spotted hyena territories, and the degree to which the group (clan / pack) defends them. For instance, in the Kalahari Desert spotted hyena densities are so low that they forage and hunt within territories too large (500-2,000 sq. km / 193-772 sq. miles) to defend against other hyenas. In contrast, where wild ungulate prey is most abundant, as in Tanzania’s Ngorongoro Crater, hyenas are numerous, forming large social groups and aggressively defending territories less than 40 sq. km (15 sq. miles) in area. (The much larger Serengeti-Mara ecosystem, which includes the crater, is home to 7,200-7,000 animals, the largest spotted hyena population in Africa.)

One night in the Serengeti, two friends of mine, staying in a guest house, experienced at close hand the aggressive defense of a spotted hyena clan territory. Hearing hyenas, they went outside and played a recording of spotted hyena calls from another area. Minutes later they had to scramble atop a nearby Land Rover to escape a crowd of angry spotted hyenas. Hearing hyenas from another clan in their territory, they had rushed over to expel them.

Another example of the spotted hyena’s complex behavior is a greater plasticity in foraging and hunting behavior than exhibited by other African carnivores. for instance, spotted hyenas both scavenge and hunt, the former usually during the day because they use vultures as indicators of kills, and the vultures only fly during the day.

However, when carcasses are scarce, spotted hyenas also hunt, usually at night, and, depending on the circumstances, either alone, in small parties, or in large groups. A common technique is to lope toward a herd or flock, forcing its members to flee, revealing easy to catch stragglers (weak, young, sick).

Like wild dogs, spotted hyenas simply run their prey to exhaustion, usually within 1.5-5 km (1-3 miles). A single hyena can catch and kill healthy prey the size of a bull gnu, but only as a last resort. When hyenas are numerous, other pack members may join in near the end of a chase to help pull down larger animals like wildebeests. However, usually led by a female, they also stage deliberate pack hunts of dangerous prey, such as zebra families guarded by sharp-hoofed stallions.

Often eating their prey alive, spotted hyenas, unlike wild dogs (https://storiesofeastafrica.com/2023/09/13/wild-dogs-wildlife-of-ngorongoro/), compete with other pack members by eating as much and as fast as they can, with individuals swallowing up to a third of their weight (A lion can only swallow a fourth of its weight). Twenty hyenas, and another group of 35, were recorded finishing off carcasses weighing 100 kg (220 lbs.) and 220 kg (485 lbs.) respectively, in 13 minutes. And they do this with remarkably little fighting. Instead, there’s lots of noise, which attracts other clan members (up to 65 seen on a kill in Ngorongoro Crater). Only then do all clan members ever come together. (These competitive scrambles are less common in the Serengeti where there is a better ratio of prey to hyena.)

Spotted hyenas also excel in that they eat almost the entire carcass of their prey. They can, for instance, crack quite large bones, such as those of buffaloes and giraffes, noisily splintering them before they are swallowed. Furthermore, their digestive system can dissolve bones, and even teeth, within hours. (Dry hyena scats, composed of ground up bones, are a chalky white.). Thus, virtually everything is eaten except the rumen contents (Grass! Yuck!), and horn bosses of larger antelopes. The hair, and hooves, which cannot be digested, are disgorged. Probably no other carnivore utilizes vertebrate prey so efficiently. Other species waste up to 40% of their kills.

Hans Kruuk found the spotted hyena to be a formidable predator. This to the extent that lions often scavenge hyena kills. Direct competitors with lions for food, spotted hyenas, unless present in large groups, generally give way to the larger carnivores, allowing them to appropriate their kills. In turn, spotted hyenas frequently steal kills made by cheetahs and wild dogs (although the latter, being more socially cooperative, are sometimes able to successfully defend themselves) and, given the opportunity, also kill their cubs, as do lions. In the Serengeti, lions and hyenas have exerted such pressure on wild dogs that they have pushed them into outlying parts of the greater Serengeti ecosystem.

Furthermore, spotted hyenas can be dangerous to livestock and people, especially when other food is scarce, but also when an opportunity arises for an easy meal, such as encountering an unattended child, or someone sleeping in the open. A relevant example (see below) recently appeared in my local newspaper.

On the other hand, spotted hyenas keep ungulate herds healthy by weeding out the weak. They also act as nature’s health police by disposing of carcasses left by other carnivores, droughts, disease epidemics (they even eat diseased carcasses), and humans. (For a video on the latter subject see (https://news.umich.edu/hyena-scavenging-provides-public-health-and-economic-benefits-to-african-cities/)

Furthermore, spotted hyenas are easily kept and trained. Witch doctors sometimes add to their persona by keep them as pets. Hans Kruuk and his wife, Jane, successfully raised a young hyena as a family pet in the Serengeti National Park, although they eventually put it in a zoo when it learned how to open doors and steal bacon from the chief park warden’s breakfast table.

Spotted hyenas: Complicated creatures. Just like us.

REFERENCES

Estes, R.D. 1992. The Behavior Guide to African Mammals: Including Hoofed Mammals, Carnivores, Primates. The University of California Press.

Fosbrooke, H. 1972. Ngorongoro–The Eighth Wonder. Andre Deutsch.

Herlocker, D.J. 2009. Buffaloes by My Bedroom: Tales of Tanganyika. iUniverse.

Kruuk, H. 1975. Hyaena. Oxford University Press.

Ngorongoro Hyena Project (https://hyena-project.com)

Check out the Ngorongoro Hyena Project webpage for excellent photos and videos, and for information about on-going research.

CCA ATTRIBUTIONS

*Creative Commons Attribution Share 2.0 Alike license.

** Creative Commons Attribution 3.0 Unported license.