Monday, 
August 28, 2017

Predators of Africa Rocks

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When most people think about Africa’s predators, big cats like lions may come to mind, or perhaps efficient pack hunters like hyenas. However, the new Conrad Prebys Africa Rocks turns the spotlight on many colorful, smaller, and lesser-known predators that are equally fascinating—and all are major players in their own habitats.

Wait for It

Found in West Africa’s rain forests, rivers, swamps, and streams, the West African dwarf crocodile is an opportunistic predator that eats mostly invertebrates. While it will go after prey as small as millipedes, beetle larvae, worms, snails, crabs, frogs, and shrimp, this small croc also preys on fish, reptiles, birds, and small mammals. It can reach five feet in length, and its dark coloration helps it blend into its surroundings, making it look like a partially submerged log or a tree limb. [caption id="attachment_122880" align="aligncenter" width="1200"] NO NEED TO RUN
While it may climb onto tree branches or wander along forest trails, the West African dwarf crocodile mostly just sits in shallow streams and waits for prey to get close enough to eat.[/caption] In addition to their affinity for the water, dwarf crocodiles have the surprising ability to climb into the lower branches of trees. Their hunting strategy is to sit in shallow streams and wait, and ambush their prey. Dwarf crocodiles can hold their breath for up to an hour in water, waiting for prey to get close enough to catch. Dwarf crocodiles hunt at night, often venturing into the forest. They spend their days resting in the water or basking in the sun. “We’re very excited about the West African dwarf crocodiles’ new exhibit at Africa Rocks,” said Kim Lovich, curator of herpetology and ichthyology at the San Diego Zoo. “Their previous exhibit was smaller, so we think they will be in Shangri-la here.” She added that featuring West African dwarf crocodiles in Africa Rocks gives some much-needed attention to crocodilians—an important and underappreciated group of animals, from a conservation standpoint. “There are only 24 recognized crocodilian species, and 44 percent of them are threatened with extinction,” Kim said.

Top Predator

Is it a cat, a dog, or something else? Found only in the forested island habitat of Madagascar, fossas may look a little like both, but they are actually more closely related to the mongoose. Although their body length is only 27 to 31 inches, plus a 26- to 28-inch tail, and they weigh just 12 to 22 pounds, fossas are Madagascar’s top predator. “They are Madagascar’s equivalent to a mountain lion or cougar,” said Carmi Penny, director of Collections Husbandry Science and curator of mammals at the San Diego Zoo. Fossas are remarkably effective in their habitat, yet only an estimated 2,600 to 8,600 of this species still exist. [caption id="attachment_122882" align="aligncenter" width="1000"] GET A GRIP
The fossa’s sharp, retractable claws help it climb trees with ease, to pursue a potential meal.[/caption] While they also prey on reptiles, wild pigs, rodents, and birds, the fossa’s main food source is lemurs—and fossas keep the island’s lemur population in check. Fossas are wily ambush hunters that hunt alone, day or night, and stealthily disappear into their surroundings. They may lie in wait for their prey, but they are fast and agile enough to maneuver through the treetops, and outrun even the fastest lemur. Their sharp, catlike, retractable claws make them both skillful tree climbers and excellent at catching prey. The long tail helps them balance while traversing tree branches, and sharp teeth make short work of captured prey.

My, What Big Ears…

Weighing less than 40 pounds, with large ears and an elongated body, the serval has an unusual look. However, its odd characteristics help make it an excellent hunter. Those big ears help give servals remarkable hearing—in fact, servals have ultrasonic hearing, able to detect inaudible (to us) sounds of rodents in their burrows. And those long limbs give servals the ability to leap, nine feet, straight up, to catch birds in midair, or reach deep into a rodent burrow to pull out prey. Their long, curved claws allow them to snag their quarry with ease, helping them grab fish or frogs right out of the water. [caption id="attachment_122884" align="aligncenter" width="1000"] WHAT’S THAT?
Large ears and ultrasonic hearing help the serval locate rodents, even when their prey is hiding in a deep burrow.[/caption] Servals live in the savannas of central and southern Africa, in areas with heavy vegetation near streams and rivers. Their diet includes small mammals, birds, reptiles, frogs, fish, crabs, and large insects. Considered the most efficient hunter of all the cats, the serval is successful in about half of its hunting attempts, while most other cats catch prey in one out of every five or six attempts. Servals use a variety of hunting styles, but they generally ambush prey instead of chasing after it. After waiting in the tall grass, listening patiently, a serval pounces, using its full body weight to come down on its prey with maximum force, and killing it quickly with a bite to the neck. At the San Diego Zoo, servals have long been popular as animal ambassadors. Their spectacular skill at leaping and catching prey stand-ins (such as feathered bird toys suspended from long sticks) can be seen in the Zoo’s Animals in Action experience. “The serval is a valuable animal ambassador that helps us communicate with the public about our conservation mission,” Carmi said.

Compact Carnivores

The dwarf mongoose is the smallest carnivore in Africa. Measuring 7 to 11 inches in length, it has a long, furry tail, small ears, a pointed muzzle, and teeth that can grind and cut through tough exoskeletons—making it well adapted for an insect-heavy diet. Its curved claws are ideal for burrowing and uncovering insects. [caption id="attachment_122886" align="aligncenter" width="1000"] PINT-SIZE PREDATOR
The dwarf mongoose has claws designed for digging and teeth built for cutting through tough exoskeletons of the large insects it catches and eats.[/caption] With a cooperative lifestyle similar to that of its meerkat cousins, the dwarf mongoose lives in groups of 8 to 30 individuals, often occupying termite mounds, hollow logs, or rocky outcroppings. Found in open woodland and savanna habitats, the group spends its days foraging for food. In addition to insects, dwarf mongooses eat rodents, reptiles, eggs, and fruit. Dwarf mongooses not only hunt together, but they also groom each other and watch out for each other. An alpha male will serve as a lookout for the group, and he will sound an alarm if he sees potential danger approaching, such as snakes or birds of prey.

Tenacity Pays

Honey badgers, also known as ratels, have a well-earned reputation for being fearless and tenacious. Found in deserts, forests, and grasslands of Africa and Asia, honey badgers will do whatever it takes to succeed. “The honey badger’s most notable characteristic is its extraordinary aggression,” Carmi said. “They will take on everything from a snake to a jackal.” Other animals are hesitant to tangle with a honey badger, for good reason. [caption id="attachment_122891" align="aligncenter" width="900"] TOUGH GUY
With sharp claws and powerful legs, the tenacious honey badger can dig rodents and reptiles out of their burrows or tear up a termite mound or beehive. If it is hungry or feels threatened, this fearless predator won’t hesitate to go after just about any other animal, large or small.[/caption] Honey badgers have strong teeth, a massive skull, and tough skin that is loose enough to allow it to turn around and bite an attacker. It has a stocky, flattened body with short and powerful legs; and it can repel threats with a powerful skunk-like odor from a gland at the base of its tail. With long, sharp claws, the honey badger handily defends itself. It also uses those claws to dig burrows—up to five feet deep and nine feet long—where it sleeps during the day. At night, when it’s time to go hunting, the honey badger digs up rodents and reptiles burrowed deep, or rips through a beehive to find its favorite food: bee larvae. Honey badgers will also go after a variety of small mammals, birds, and insects—and they will sometimes eat carrion, vegetation, and fruit.

Aerial Hunter

Both predator and scavenger—with a vulture’s ability to feed on carrion, and an eagle’s ability to hunt and kill snakes and other prey with its feet—the bateleur eagle is both versatile and unique. Found in savannas and grasslands of sub-Saharan Africa, the bateleur eagle is known for its low, back-and-forth aerial searches for food on the land below, and its ability to descend in a tight spiral, plummeting toward the ground at high speed to retrieve its prey. The bateleur is known as a snake hunter, and it can even kill and eat venomous snakes. When it goes after a snake, the eagle often raises its crest feathers and spreads its wings in a distinctive display. It also hunts a variety of reptiles, other birds, and mammals. It occasionally catches fish, eats eggs of other birds, and dines on termites. The bateleur eagle may also steal food from other predators—a practice known as kleptoparasitism. When live prey is not available, the bateleur eagle feeds on carrion. Its unfeathered pink facial skin, like that of a vulture, is easier to keep clean to resist potentially harmful bacteria found on decaying meat. [caption id="attachment_122890" align="aligncenter" width="900"] SNAKE HUNTER
The bateleur eagle uses its sharp talons and powerful feet to catch and kill snakes and other prey. If prey is not available, this raptor can eat carrion—and its bare facial skin helps resist bacteria.[/caption] You don’t have to be large to be important to your ecosystem. Africa Rocks predators are big enough to keep populations of many other animals—ranging from insects and rodents to birds, reptiles, and small mammals—at healthy numbers. Each uses a specialized hunting strategy or predatory style, and their adaptations help them excel in their specific habitats.