Bat-Eared Fox

Bat-Eared Fox

[ Otocyon megalotis ]

Quick Facts

BODY LENGTH: 18.1 to 22.9 inches
TAIL LENGTH: 9.5 to 13.4 inches
WEIGHT: 6.6 to 9.9 pounds
WILD DIET: insects and other invertebrates, small rodents and reptiles, fruits, and bird eggs
ZOO DIET: canine chow, crickets, mice, ribs, chopped fruit, ground meat, and vegetables
DISTRIBUTION: two populations: the southern population from southern Zambia to South Africa; the northern population from Ethiopia to Tanzania
HABITAT: open grasslands

 

Big Ears, Small Fox

Claim to fame
This small African fox lives on the savannah and semi-deserts of eastern and southern Africa, successfully occupying a unique place in the ecosystem among far larger and more formidable predators. A small, pointed nose and rounded back suggest a timid demeanor, and in fact these little hunters rely on stealth and cunning more than brute strength. Their buff-gray coat and black trim on the face, ears, legs, and tail tip blend in well with grass and shrubland habitat, and are unlike any other canid’s (member of the dog family).

But what really sets these foxes apart from the pack are their incredible ears. They are huge and cupped, seeming to belong to a much larger animal! Along with a broad forehead, the ears look something like a bat wings spread in mid-flight---hence the name! Only the much tinier and paler fennec fox has ears that are larger relative to body size. As unique as their ears are, the real claim to fame of these foxes is their diet.

Bucking a trend
Of all the canids, the bat-eared fox alone has, through years of evolution, given up meat as its main diet. Small and relatively weak teeth hint at a diet that’s easier to chew than meat, and these foxes chow down on fruits, scorpions, spiders, and the occasional small mammal or lizard. What bat-eared foxes lack in fang power, they make up in the ability to chew food more rapidly than most carnivores. Why would these foxes need to eat so quickly? Because the majority of their diet is insects. And you have to eat pretty fast if you’re going to fill up on bugs!

Termites, again?
Harvester termites make up about 50-70% of a bat-eared fox’s diet. The little canids are so dependent on these insects for food that the ranges of the two species overlap almost exactly. Termites are readily available because they emerge night and day to harvest grass, providing a banquet for bat-eared foxes. The foxes move around among the busy colony, lapping up termites by the hundreds. But, besides being a main course, harvester termites help bat-eared foxes in another way, too.

Dung happens
The harvesting activity of thousands of termites is so overwhelming that in some areas they create barren patches of ground. These areas stripped bare by termites offer up another treat to eat for bat-eared foxes. When sunlight hits the recently cleared ground, grass seeds in the soil rapidly sprout into tender new shoots. Big herds of grazers, such as zebra and wildebeest, are attracted to the nutritious growing grass. What happens when there are lots of big herbivores around? Dung, and lots of it. And what comes after dung? Dung beetles, of course, which just happen to be another bat-eared fox favorite. The beetles gather balls of dung and roll them to their burrows to provide a food source for their future larvae. The adult dung beetles may fall victim to foxes in mid-roll, however, providing a crunchy alternative to termites. Some of the larvae, rich in nutrients, are excavated from the ground by industrious foxes, as well.

Now hear this
Along with performing the more pedestrian hearing duties, the big ears of bat-eared foxes are sensitive hunting tools for locating underground invertebrates, such as dung beetle larvae. A foraging fox looking for subterranean food moves about, starting and stopping, ears cocked to pick up the sound of underground movement. When the fox detects something, it narrows in on the sound by swiveling its ears back and forth. Ears cupped like radar antennae, the fox stands above the source of the sound, fixing its position exactly. After a few seconds of frenzied digging, the bat-eared fox is usually rewarded with a juicy larva or millipede.

Get Involved

Conservation Fund of the Chicago Zoological Society