Spotted Hyena (Crocuta crocuta)

• Type: Mammal
• Family: Hyaenidae
• Habitat: Savanna, semi-desert, and other dry, open areas
• Location: Sub-Saharan Africa, except for tropical rainforests
• Diet: Antelopes and other large ungulates. Also carrion, bone marrow, and bones
• Average lifespan in the wild: 19 years
• Size: Head and body length 37.4-59 in (95-150 cm); height at shoulder 29.5-33.5 in (75-85 cm)
• Weight: 120-190 lbs (55-85 kg) for females; 100-135 lbs (45-60 kg) for males

Unlike the three other species in the family Hyaenidae, spotted hyenas are expert hunters. They do scavenge sometimes, but — contrary to popular belief — spotted hyenas catch about 95 percent of their food. Spotted hyenas are both the most abundant and the most successful large predator in Africa. Built for endurance, spotted hyenas often hunt in packs, chasing prey to the point of exhaustion. Then the hyenas move in and use their powerful jaws and strong teeth to bring the hunted animal down. Packs of spotted hyenas can bring down an animal as large as a giraffe, a zebra, or even an African Cape buffalo.

Spotted hyenas have very powerful shoulders and front legs, but their hindquarters are not as well developed, giving the hyena its sloping appearance. Its head is very large, and its jaws are strong enough to split open rhino bones and extract the marrow. The ears are rounded, and the neck long and muscular. Each spotted hyena has a unique spot pattern, although spots can fade with age, especially in females. Females are about 10 percent larger than males, and are also more aggressive.

Spotted hyenas are more closely related to cats than dogs, despite their dog-like appearance. Their closest relatives are actually mongooses and civets. Unlike all other carnivores, spotted hyenas have a complex social system where animals live in female-dominated clans of up to 90 individuals. To live and interact in such a large clan requires a great deal of social intelligence.

These clans closely resemble the social systems of old world primates such as baboons and macaques, where the social rank of a female is solely determined by the social status of its mother. Age, size, and fighting ability play no role in determining the hierarchy, and females on the top of the social ladder have priority access to food. To cope with competition for food, spotted hyenas spend most of their time in subgroups. Even though the whole clan is rarely seen together, each individual can recognize the identity and social rank of every other member of the clan. Spotted hyenas use various different vocalizations to communicate identity and social status, including whoops, growls, groans, and submissive giggles.

Having so many individuals in a clan helps spotted hyenas defend large home ranges, up to 40 square miles. They mark their territory with feces and urine and often patrol their borders. Large clashes or wars between clans over territory can occur. Males in the clan are mainly immigrants and always enter at the bottom of the hierarchy, below the lowest females. Only by making alliances with females can males mate; higher-ranking females choose to mate with males that have been in the clan for the longest. Breeding occurs throughout the year, and females give birth to one to four offspring per litter, though twins are most common.

Did you know:  The female spotted hyena has an enlarged clitoris or pseudo-penis and fused labia housing two pouches of fatty tissue that closely resemble a male scrotum. These features make the sex organs of the female almost indistinguishable from the male.

Photo by Stig Nygaard, Flickr

Guereza Colobus (Colobus guereza)

• Type: Mammal
• Family: Cercopithecidae
• Habitat: Deciduous and evergreen forests
• Location: Across central Africa
• Diet: Leaves and fruit
• Average lifespan in the wild: 20 years
• Size: Head and body 20.5-27.5 in (52.1-69.9 cm); tail 20.5-39.4 in (52.1-100 cm) 
• Weight: 17.2-20.3 lbs (7.8-9.2 kg) for females; 20.5-29.8 lbs (9.3-13.5 kg) for males

Also known as the eastern black-and-white colobus, or the white-mantled colobus, guereza monkeys have a glossy black coat with beautiful white markings. A mantle of long white hairs adorns their back in a U-shape from their shoulders to the base of their tail. Guerezas have a hairless gray face that is also surrounded by white. Their long tail can be either white or yellowish in color, with a large tuft of white fur at the end. This distinctly marked tail is as long as their head and body combined.

Guerezas have a specialized stomach with two different regions, similar to a cow’s stomach, which helps them digest plant cell walls and fibers from their leafy diet. The upper region of the stomach also contains strains of anaerobic bacteria that aid in digestion. This complex stomach allows guerezas and other colobus monkey species to feed on large quantities of leaves. They also eat fruit. Guerezas live in various habitats across equatorial Africa and as a result their diet can be diverse. Their tough stomachs allow them to digest this variety of food.

Guerezas live in small cohesive groups of 8 to 15 individuals. They spend half their day traveling and feeding. Individual guerezas take turns leading the group to different feeding sites, using quadrupedal motion to travel through the trees. Their hands and feet are adapted especially well for this kind of motion through the forest, grasping and walking on tree limbs. Guerezas also run through tree tops, bounding up and galloping across branches, though they usually make only short leaps across horizontal distances.

Guerezas spend the other half of their day at rest. Between feedings, the group takes breaks to relax and groom each other, and after traveling and feeding during the day, a guereza group will congregate each night before sunset in several adjacent sleeping trees. Most groups consist of one male, several adult females, adolescents, and young. Guereza groups often live close to each other or in overlapping territories, though each group is very territorial. At dawn and dusk, males will “roar” as a way of signaling their territory to other groups.

Did you know: The guereza’s genus name colobus comes from the Greek kolobos, meaning “curtailed” or “mutilated,” appropriate because the animal has only four digits on each hand. Its lack of a thumb may be an adaptation to allow for rapid movement through trees.

Photo by Yoky, Creative Commons license.

Blue Wildebeest (Connochaetes taurinus)

• Type: Mammal
• Family: Bovinae
• Habitat: Savanna
• Location: South and east Africa
• Diet: Grasses
• Average lifespan in the wild: Up to 20 years
• Size: Body and head 5.6-8 ft (1.70-2.40 m); shoulder height 3.8-4.8 ft (1.15-1.45 m)
• Weight: 260-594 lbs (118-270 kg)

Blue wildebeests exist in a variety of colors, despite their name. There are gray, brown, light, and dark wildebeests, but all have a black mane and tail, short hair, a beard, and dark vertical bands on their neck and shoulders. They have a small hump above their forelimbs, and their profile is slightly sloped. Both sexes of blue wildebeest have horns that grow outward to the side and curve slightly inward at the top. The horns do not have ridges, and can grow up to 1.3 feet long in females and 2.7 feet long in males.

Females and their young form herds of anywhere from 10 to 1,000 individuals. Young males form bachelor groups, but most adult males are solitary and territorial. Males use their horns in shoving matches and disputes over territory. Only males with territory have access to breeding females. During the dry season, divisions between groups break down and massive migratory herds form. They follow rain storms in search of sprouting grasses, their preferred food. During these migrations, wildebeests traverse much of the Serengeti and, though they do not move as a single unit, over 1.8 million individuals move towards wetter areas. Zebras and Thompson’s gazelles also follow a similar migratory path, and travel alongside wildebeest herds. Zebras and wildebeests prefer the same type of grass, but eat different parts of the plant, which means they coexist well together. Zebras also have superior vision and hearing, which wildebeests benefit from. Young wildebeests often watch zebras for signs of alarm.

Blue wildebeests give birth to one calf at a time during a synchronized birthing season in February. A calf can stand on its own six minutes after birth. It is important that offspring be able to keep up and follow the mother closely, as young are the most vulnerable members of the herd. Lions, spotted hyenas, leopards, African wild dogs, and cheetahs all prey on young wildebeests. Adult wildebeests can flee from predators at over 50 miles per hour.

Blue wildebeests typically drink two times per day, and thus access to watering sites is crucial. They forage most actively in the morning and the evening, and rest during the hottest parts of the day. Since wildebeests are so reliant on seasonal rain patterns, global warming and climate change could severely disrupt or damage herds.

Did you know: More than 500,000 wildebeest calves are born over a 2 to 3 week period during the synchronized birthing season in February.

Photo by Hans Hillewaert, Creative Commons license.

Bat-Eared Fox (Otocyon megalotis)

• Type: Mammal
• Family: Canidae
• Habitat: Short-grass plains and areas where termites and beetles are found
• Location: Two distinct populations in southwest and northeast Africa
• Diet: Insectivore
• Average lifespan in the wild: 6 years
• Size: Head and body 18.1-26 in (46-66 cm); tail 12-14 in (30-35 cm)
• Weight: 4.9-9.9 lbs (2.2-4.5 kg)

The ears of bat-eared foxes can grow up to 5.3 inches long. For an animal that stands 11.8-15.7 inches at the shoulder, that’s enormous. Bat-eared foxes use these specialized ears to locate termites, dung beetles, and other insects, which make up most of their diet. Bat-eared foxes can hear larvae chewing their way out of an underground dung beetle ball. They can also detect the sound of harvesting termites chewing on short grasses.

The body of the bat-eared fox is ashy gray in color with black limbs and tail. The backs of its enormous ears are also black, and it has a raccoon-like white facemask. The underside of its neck and belly are paler than the rest of its body.

Bat-eared foxes are hunted by several different mammal species, including cheetahs, jackals, spotted hyenas, rock pythons, African wild dogs, and leopards. Their large, bushy tails work as a rudder when fleeing from predators in a zig-zag pattern. They are fast and good at dodging, but their best chance at escaping predation is by fleeing to their underground dens, which have several entrances and multiple chambers connected by tunnels. A bat-eared fox family may have several dens throughout their home range.

Bat-eared foxes are also preyed upon by raptors and must keep a watchful eye while foraging. Most of their foraging is done alone at night. While looking for food, bat-eared foxes walk slowly and quietly with their noses to the ground and their ears cocked forward, listening for insects.

Surviving on an all-insect diet required several adaptations in the bat-eared fox. In addition to their large and powerful ears, bat-eared foxes have specialized extra teeth for chewing up insects, and their lower jawbone is designed to open and close rapidly.

Pairs or groups are often found residing near one another, and individuals come together at dusk to play and groom each other. Bat-eared foxes mate for life, and sometimes two females will mate with one male and share a communal den. The father is very invested in the rearing of young, and he spends a great deal of time babysitting. While the father is watching the cubs, the mother is free to forage for food, including insects, which are a steady food source.  Though they are low in nutrition and cannot be regurgitated for the young, they allow the mother to take in the necessary amount of food needed to produce milk for the cubs.

Did you know: Bat-eared foxes play an important role in termite control. A single bat-eared fox can eat approximately 1.15 million termites each year.

Photo by Hans Hillewaert, Creative Commons license.

Queen Naked Mole-Rat (Heterocephalus glaber)

• Type: Mammal Family: Bathyergidae
• Habitat: Underground in arid savannah and grasslands near the equator.
• Location: Parts of Kenya, Ethiopia, and Somalia.
• Diet: Herbivore
• Average lifespan in the wild: 10 years
• Size: Naked mole-rats range from 3-13 inches (8-33 cm); queen is usually largest and longest in the colony.
• Weight: Usually over 1.8 ounces (50 g); may reach 2.8 ounces (80 g).

The naked mole-rat, which is in fact neither a mole nor a rat, is one of only two “eusocial” mammals; as with social insects such as bees and ants, young are produced by only one female in a colony — the queen. In the case of naked mole-rats, the queen mates with one to three breeding males. The colony’s other females are sterile. Research suggests that this is because of the queen’s bullying tactics. She literally shoves around the other females, and her aggression causes the female mole-rats so much stress that it affects their fertility.

But the queen is good to her pups, and tends them diligently — with the help of the rest of the colony. Queens typically produce a litter of about 11 to 12 pups, although litters with as many as 27 pups have been noted. The queen will nurse her pups for about a month, and then the pups join their colony mates on the mole-rats’ regular diet of underground plant parts, like roots and succulent tubers. Naked mole-rats get all of their water from their food (and the queen, dutifully tended to by her subjects, gets all of her food served to her).

Mole-rats are well adapted for life underground. The eyes are narrow slits, and eyesight is poor, but their hearing is acute, and they can sense vibrations; their large, protruding teeth are used for digging, their lips are sealed just behind those teeth so they don’t get a mouthful of dirt as they burrow, and they can move backwards as easily as forwards. The wrinkled, pink or yellowed skin of the naked mole-rat’s tubular body has sensory whiskers on the head and tail, and tufts of hair between the toes, so the feet act like brooms. Other oddities include skin that cannot sense pain, and an essentially cold-blooded metabolism.

Did you know? Naked mole-rat tunnel systems can have a cumulative length of two to three miles.

Related Programs:

• The Beauty of Ugly

Red Fox (Vulpes vulpes)

• Type: Mammal
• Family: Canidae
• Habitat: Highly variable. Edge forests, deserts, tundra, cities, and suburban areas
• Location: Most of the Northern Hemisphere and Australia
• Diet: Rodents, birds, insects, carrion and fruit
• Average lifespan in the wild: 3 years in the wild; 10-12 years in captivity
• Size: Head and body 18-35.4 in (45.5-90 cm); tail 11.8-21.8 in (30-55.5 cm)
• Weight: 6.6-30.8 lbs (3-14 kg)

The small, slender bodies of red foxes are designed for speed and agility. In proportion to other canid species, red foxes have longer legs and smaller stomachs — adaptations that allow the animal to run nearly 30 miles per hour. A smaller stomach means they need to eat more often, and red foxes opportunistically eat a wide variety of foods as they traverses their home range at night, such as insects, fruits, earthworms, and scraps left by humans. Although they also hunt during the day, red foxes have very acute senses to help them succeed as nocturnal predators. Their eyes are designed to work well in low light conditions, and they maneuver their erect triangular ears to locate the faint rustling noises of rodents. When a mouse is detected, red foxes stand alert and motionless, using their ears and eyes to pinpoint the location of the rodent. Then they launch themselves into the air at a 45-degree angle, and land on the mouse, pinning it to the ground.

Red foxes are territorial, and mark their home range using feces and urine. A dominance hierarchy determines who breeds, and the dominant female gives birth each year to a litter of 3 to 12 pups. Mothers keep their offspring in dens, and non-breeding adults help care for the young. There are several different red fox color variants, which can often be seen within a litter. These include the silver, black, and cross variants. All red foxes have thick fur, a wide, bushy tail, and a narrow, pointed muzzle.

Red foxes have the largest distribution of any canid species. They can be found in almost the entire northern hemisphere, in part because they have such a diverse diet. As a species, red foxes have adapted well to human expansion. They thrive in urban areas, and have benefited from the human conversion of forest into agricultural lands. Red foxes are often seen as a threat to poultry and young livestock, even though they usually prey only on weak and sick animals. Though many farmers consider them pests, red foxes play a major role in controlling populations of crop-threatening animals like rabbits and rodents.

Did you know: Red fox predators are eagles, coyotes, gray wolves, bears, mountain lions, and humans, who have been hunting red foxes since the 4th century BC.

Photo by Otmar Penker © ORF / Die ARGEntur Filmproduktions GmbH

Giant Kangaroo Rat (Dipodomys ingens)

• Type: Mammal
• Family: Heteromyidae
• Habitat: Sandy, arid grasslands
• Location: Western central California
• Diet: Seeds and grains
• Average lifespan in the wild:  9.8 years
• Size: Head and body 6-7.8 in (15-20 cm); tail 7-8.5 in (18-21.5 cm)
• Weight: 3-6.3 oz (93-195 g)

Giant kangaroo rats are aptly named—they bound across California grasslands with their elongated hind legs and feet. Their long tail is used for balance, and their short neck and large, flattened head help giant kangaroo rats travel almost exclusively via bipedal motion. The erratic path of their powerful jumps and top speeds of almost 10 feet per second makes them very hard for predators to catch.

Giant kangaroo rats live alone in underground burrows on sandy slopes. Inside each borrow they keep a large cache of seeds and grains. The rats are nocturnal, coming out every night after sunset to gather more seeds and grains into large expandable pouches in their cheeks to carry back to the burrow. Any seeds or grains that are not completely dried are buried outside the burrow under a thin layer of sand and left to dry before adding to the food hoard. Foraging trips are short. Giant kangaroo rats are very territorial and never leave their den for very long, usually only a total of 15 minutes per day.

Even though giant kangaroo rats are a solitary species, individuals do communicate with each other using scent as well as foot thumping, a behavior in which the rats hit their hind feet against the ground repeatedly. An array of specific signals are used, from single, short thumps, to long, elaborate “footrolls” that can average over 100 drums at 18 drums per second. Foot drumming helps identify neighbors, establish territory, and communicate mating status. Giant kangaroo rats will also approach snakes and foot thump at the predators in an attempt to drive them away.

Giant kangaroo rats are a critically endangered species, restricted to a small area in western central California that is only about 2 percent the size of its former range. Urban and agricultural development in California has caused massive habitat fragmentation, which means the remaining populations will probably become genetically isolated. However, giant kangaroo rats are listed as a state and federal endangered species, and protected lands and policies are in effect to help save the species.

Did you know: Giant kangaroo rats have the most concentrated urine of any North American mammal. Their kidneys are so efficient that they do not need to drink—they get enough water from the seeds they eat.

Photo by George Harrison, U.S. Fish and Wildlife Service

Bongo (Tragelaphus eurycerus)

• Type: Mammal
• Family: Bovidae
• Habitat: Lowland forests
• Location: Central and West Africa
• Diet: Twigs, leaves, fruits, and shoots
• Average lifespan in the wild: 19 years
• Size: Body length 5.6-8.3 ft (1.7-2.5 m); horns 30-39 in (75-99cm)
• Weight: 440-550 lbs (200-250 kg) for females; 440-880 lbs (200-400kg) for males

The bongo is a very striking forest antelope with a brilliantly colored hide and long, smooth, spiral-shaped horns. Both male and female bongos have horns, but the female’s horns are thinner and more parallel. Males are larger than females, reaching up to 880 lbs.

The bongo lives in Western and Central African forests. Against the trees of the forest, the thin, white, vertical stripes on the bongo’s torso help camouflage the animal by breaking up its body outline. The bongo has a colorful red-chestnut coat, a black muzzle, and legs that are patterned with red-chestnut, black, and white. The inside of its large, broad ears are outlined with white, and on either side of its face the bongo has small white markings.

As the only forest bovid that forms small herds, the bongo relies on the shrubs, bushes, and trees of the forest for both food and cover. Herd size ranges from 5 to 50 animals and is made up of mostly females and their young. Most males are solitary, but some will be present in the herd. The bongo is a very elusive species, and it is easily startled by humans. It is thus very difficult to study. During the day, the bongo stays concealed within the forest, and only at night does it come out into open areas to frequent natural salt licks and graze freely on grasses and herbs. Many mammals visit these meadows, and natural salt licks tend to be the center of activity in the bongo herd’s home range.

As a grazer, the bongo travels through the forest feeding on a wide variety of plants, but most frequently consumes young leaves and shoots, which are high in protein and low in fiber. Its digestive system does not work as well if too much fiber is consumed. The bongo also sometimes eats fruits and flowers, and it supplements its diet with grasses and herbs found near the salt licks. A hoofed animal of the bongo’s size needs to consume large quantities of food to fulfill its energy needs. Tree branches can be broken off or pulled into reach using the bongo’s long horns, and a prehensile tongue makes plucking leaves much easier.

Did you know: The bongo is the only species of spiral-horned antelope in which both sexes have horns.

Photo by Frank Wouters

Pygmy Marmoset (Callithrix pygmaea)

• Type: Mammal
• Family: Cebidae
• Habitat: Tropical rainforest, preferably seasonally flooded riverine forests
• Location: Western Amazonia; Columbia, Ecuador, Brazil, Peru, and Bolivia
• Diet: Tree sap, gums, insects, and fruits
• Average lifespan in the wild: 12 years
• Size: Head and body 4.7-6 in (12-15.2 cm); tail 6.8-9 in (17.2-22.9 cm)
• Weight: 4.20 oz (119 g)

Even though they are the smallest of all the monkeys, pygmy marmosets can leap more than 16 feet. At only 5.35 inches and 4.2 ounces on average, they expertly maneuver through the canopy, scampering vertically up trees using their sharp claw-like fingernails. All other primates have flat fingernails, but pygmy marmosets’ specialized claws are much better for gripping limbs while feeding on tree sap. The diet of pygmy marmosets is largely comprised of tree exudates – the sap, gum, resin or latex that oozes out of plants. The incisors, which are narrow and elongated, help these tiny animals gnaw holes in tree trunks to release sap. Insects and fruit supplement their diet.

Pygmy marmosets live in social groups of two to nine individuals. The dominant female is the only female in the group to mate. Every member in the group aids in the care of offspring. For the first two weeks of their lives, babies are always carried. After that time, they are left in a hole or hidden tangle of vines while the adults forage for food. As the offspring grow, they spend a great deal of their time playing in the trees. When they reach adulthood, they either remain in their natal group as a non-breeding subordinate or venture out to join a new group.

Pygmy marmosets have a v-shaped lower jawbone, and thus a pointed face. Their tales are very long compared to their bodies, measuring about eight inches and banded with faint black and tan rings. The length of their head and body combined is always shorter than the length of their tail. Their fur is a brownish yellow, and dense tufts of hair sweep back from the forehead.

Did you know: Pygmy marmosets give birth to fraternal twins at an unusually high rate — while most primates give birth to only one offspring at a time, up to 70 percent of pygmy marmosets’ births are to fraternal twins.

Photo by Malene Thyssen

Blue-Ringed Octopus (Hapalochlaena maculosa)

• Type: Cephalopod
• Family: Octopodidae
• Habitat: Shallow marine waters and tide pools
• Location: Common off the coast of Australia and the western Pacific Ocean
• Diet: Crabs, fish, and mollusks
• Average lifespan in the wild: 2 years
• Size: 5-7.8 in (12.7-20 cm)
• Weight: .92 oz (26g)

With its fascinating coloring and delicate curling arms, the blue-ringed octopus may be a beautiful creature, but this small cephalopod is also deadly. The blue-ringed octopus appears grey or beige with light brown patches when it is at rest, but when agitated its 50 or 60 bright blue rings appear and pulsate with color, as a warning. Inside the salivary glands of the blue-ringed octopus live colonies of bacteria that produce tetrodotoxin, the potent neurotoxin found in pufferfish and other animals. A bite from a blue-ringed octopus can completely paralyze and kill an adult human in a matter of minutes. There is no known antidote. The octopus itself is not affected at all by the toxin-an evolutionary prerequisite for the symbiotic relationship that has developed between the blue-ringed octopus and the toxin-producing bacteria.

The blue-ringed octopus is commonly found in shallow, sandy areas surrounding the coastal reefs of Australia and the western Indio-Pacific. It is most active after dark, and spends most of its day hidden in its nest. Like all octopods, the blue-ringed octopus has no skeleton and is thus very flexible and maneuverable. It can squeeze into tiny crevices and make dens in bottles, aluminum cans, or mollusk shells. The blue-ringed octopus is also known to burrow into sand or gravel to conceal itself.

The blue-ringed octopus feeds primarily on crabs and mollusks, ambushing from behind and enveloping prey with its eight arms. Using its bird-like beak, the octopus bites a hole through its victim’s shell to inject toxic saliva. With its arms and beak, the creature tears soft pieces from the prey, sucking the rest of the meat from the shell once it becomes partially digested by the saliva.

Packets of sperm rest in the grooved tip of the male’s modified third arm, called a hectocotylus. When mating, the male slips this grooved tip under the mantle and into the oviduct of the female through a gill slit, and transfers multiple sperm packets, or spermatophores. The female lays her eggs in several unattached clumps, which she carries in her arms until they hatch. After the young emerge from their eggs, the mother dies.

Did you know: The blue-ringed octopus, like all octopuses, has three hearts and blue blood.

Related Episode: Encountering Sea Monsters

Photo © Gary Bell / Picture Quest