Spectral Bat

MammalThe Americas

Oct 30

Vampyrum spectrum

With a wingspan of almost 1 metre (3.3 ft), the spectral bat is the largest bat in the Americas and the largest carnivorous bat in the world. It's believed to find avian prey by smell and is attracted to distress calls from small bats caught in mist nets. It's also known as the "False Vampire", because it was previously thought to feed on blood.

Dusk is falling over the rainforest and darkness has overtaken the understory. You can hear the bubbling of a stream and the waking croaks of lustful frogs. In the branches above, you hear the rustle and squawk of birds gathering to roost for the night. You hear the high-pitched cheeps of bats come out to hunt. These little furred hunters scream into the dark, searching for flying insect prey. Most barely measure 15 centimetres (6 in) from wingtip to wingtip, many are smaller than 3 cm (1 inch).

Then, from the black hollow of a tree, emerges a monster. First comes its snout; long and blunt, tipped with an upturned leaf-like nose. It yawns, baring pairs of jutting razor teeth. Its little black eyes blink away sleep. Its giant oval ears twitch to attention. It reaches out with skinny arms, grasping onto bark with large, curved claws on its thumbs. Its body is tailless and covered in a short coat of reddish-brown fur, more pale on its underside. It drops from its roost and plunges into freefall before spreading its leathery wings to a span of one metre (3.3 ft). You feel each powerful flap more than you hear it, like phantom whispers. It is a looming shadow in the pitch night, A cloaked wraith, a spectral bat.

Vampyrum spectrum

There are more than 350 bat species in the New World. Vampyrum spectrum, more commonly known as the spectral bat, is the largest. It lives in dense tropical forests throughout Central America and northern South America, typically in the lowlands and often near a river or stream. An adult weighs between 145 and 190 grams (5 - 6.7 oz), which may not seem like much, but a flying creature must keep its frame light — other common species, such as the little brown bat and common pipistrelle, weigh in under 10 grams (less than half an ounce).¹ The spectral bat, alternatively known as the "false vampire", is also the largest carnivore of its kind in the entire world.

Death Bat

This sabre-toothed, chiropteran giant was once believed to be a vampire, a blood drinker — in more scientific terms, it was thought to be sanguivorous. But this vampire is false.² V. spectrum doesn't drink the blood of its victims, it devours them. Less than 1% of all bat species eat other vertebrates and out of the over 1,400 species ³, only 9 are considered true carnivores, the spectral bat among them. It was once believed to supplement its diet with fruit, but that notion was discarded when a captive pair refused to eat a single fruit over the span of five years. The spectral bat isn't like its fox-faced, fruit-eating relatives — it is a pure carnivore.

It begins its hunt at dusk, when it exits its roost — usually located in a tree hollow, sometimes in a cave or the dark corners of temple ruins. It crawls out like Camazotz, the old Mayan "death bat", hungry for flesh. Its cry is a shrill scream, ranging into the ultrasonic, that echoes through the dense forest, hitting trees and bouncing back to the spectral bat's massive ears. In flight, it uses echolocation to navigate the tangle of branches and vines. Its wings are wide but it can still weave through the most cluttered spaces, flying slow and low along the ground.

Its diet ranges from the avian to the mammalian. It employs its echolocation to scope out its prey, as other bats do, using sonar in the dark. But it's not completely reliant on its own echoes. Its ears pick up the distressed calls of smaller bats, tangled in the mist nets of well-meaning researchers or ill-intentioned poachers. Its eyes too pick out prey for the taking, such as overconfident rodents on the forest floor. But, atypical among "small" bats, the spectral is thought to locate its avian prey by smell.

Those of us with less sensitive olfaction might miss the many scents that suffuse the rainforest air, but, to the spectral bat's inverted leaf-nose, the odour of nesting birds is strong. Its preferred avian victims are gregarious and smelly. Birds who roost on exposed branches, rather than sheltered within a cavity, are more likely to be snatched from their "beds" by this bat-boogieman. It approached quietly, a stalking nightmare, before massacring a roost of unsuspecting birds with gnashing teeth and stabbing thumb-claws. It hunts parakeets, wrens, orioles and trogons. It kills cuckoos, devours doves, and murders motmots. The remains of 84 birds, comprising 18 species, were once found in a single spectral bat roost.

Blood Ties

But this nocturnal monster has a more tender side.

Male bats generally make for neglectful fathers — out of all the bat species, there are only two in which males are known to care for their young. One of them is the spectral bat.

Unlike most other bats, the spectral bat is believed to form monogamous pairs, possibly for life. Couples take up residence in a roost, creating a nesting group of up to five individuals — likely the two breeding parents and two or three children. Both parents care for their young. While one parent is out hunting, the other always remains in the nest to watch over the pups. That night's breadwinner, whether mum or dad, returns from the hunt to share food among the family and, as they settle down with full bellies to sleep through the day, the male encloses his family with a hug from his vast wings. The male spectral bat, a rarity among his kind, is a family man.

Clockwise from left; common vampire bat (*Desmodus rotundus*), white-winged vampire bat (*Diaemus youngi*), and hairy-legged vampire bat (*Diphylla ecaudata*).

¹ Some common bat species do get larger than pipistrelles and little browns. The greater horseshoe bat can weigh up to 34 grams (1.2 oz), the hoary bat up to 38 grams (1.3 oz), and the common vampire up to 40 grams (1.4 oz). This is, of course, excluding the fruit bats, or flying foxes, which get much larger.

² Of the over 1,400 species of bat, only 3 are actual vampires — mini-vampires, all less than 10 centimetres (3.9 in) long. There is the white-winged vampire bat, which feeds mostly on the blood of birds. As does the hairy-legged vampire bat, although both will occasionally partake in a mammalian blood meal. But the mammal specialist is the common vampire bat, which often drinks the blood of sleeping livestock, like cattle and horses. These are mostly vampires of the tropics, ranging from Mexico to northern Argentina, and although they rarely bite people, they do pose a risk as vectors of diseases like rabies.

Honduran white bat (*Ectophylla alba*) on the left and bumblebee bat (*Craseonycteris thonglongyai*) on the right.

³ The spectral bat, with all of its metre (3.3 ft) of wingspan, is a "microbat". That is, it belongs to the group of microbats (Microchiroptera), within the larger order of all bats (Chiroptera). And while the group's name isn't very descriptive of the spectral bat, most of its relatives are indeed micro.

Some truly micro bats include the adorable Honduran white bat, with a wingspan of 10 cm (3.9 in) and a weight of 6 grams (0.21 oz), and the bumblebee bat — the world's tiniest bat by weight — with a wingspan of 16 cm (6.3 in) and weight of under 2 grams (0.07 oz).

Most bats are, in fact, microbats.
The megabats (Megachiroptera), also known as fruit bats — fox-faced and mainly frugivorous bats that live throughout the tropics of Africa, Asia, and Australia — are comprised of around 200 species. The other 1,200 or so bat species are considered microbats.

**Where Does It Live?**

⛰️ Dense forests below 1,650 m elevation; usually near a river or stream.
📍 Central and South America; from southern Mexico to central Brazil and Peru.

‘Near Threatened’ as of 15 January, 2018.

IUCN

Size // Medium
Wingspan // 0.7–1.0 m (2.3–3.3 ft)
Length // 135–147 mm (5.3–5.8 in)
Weight // 134–189 g (4.7–6.7 oz)
Activity: Nocturnal 🌙
Lifestyle: Social 👥
Lifespan: Up to 5.5 years
Diet: Carnivore
Favourite Food: Birds 🐦
Class: Mammalia
Order: Chiroptera
Family: Phyllostomidae
Genus: Vampyrum
Species: V. spectrum

Out of the over 350 species of bats in the Americas, the spectral bat is the largest, with a wingspan that ranges from 0.7 to 1.0 metres (2.3 - 3.3 ft).

With a weight of between 145 and 190 grams (5 - 6.7 oz), the spectral bat is also hefty compared to common bat species — like the hoary bat, which weighs up to 38 grams (1.3 oz), or the little brown bat, which weighs less than 10 grams (less than half an ounce).

The spectral bat belongs to the family of New World leaf-nosed bats (Phyllostomidae), but it's the sole species in its genus (Vampyrum).

Only some fruit bat species are larger than the spectral bat — such as the Indian fruit bat, with a wingspan of up to 1.5 m (4.9 ft) and a max weight of 1.6 kg (3.5 lbs or 56 oz).

The spectral bat is the largest carnivorous bat in the world, but its competition is slim. Less than 1% of all bat species eat other vertebrates and out of the over 1,400 species, only 9 are considered true carnivores, the spectral bat among them.

It was once believed to supplement its diet with fruit, but that notion was discarded when a captive pair refused to eat a single fruit over the span of five years.

This species is also known as the "false vampire" because it was once believed to feast on blood.

Of the over 1,400 species of bat, only 3 are actual vampires; the common vampire bat, the white-winged vampire bat, and the hairy-legged vampire bat.
All three are mini-vampires, all less than 10 centimetres (3.9 in) long.

The spectral bat feeds on birds, rodents, and smaller bats — hunting them at night.

It uses echolocation to navigate in the dark and, despite its wingspan, it can deftly navigate the tangled rainforests it calls home. It flies with slow wing flaps, close to the forest floor.

It's believed to mostly use its sense of smell to find roosting birds — having a preference for gregarious and smelly aves that roost on exposed branches. It stalks up stealthily and snatches them from their "beds" in the dark.

The remains of 84 birds, comprising 18 species, were once found in a single spectral bat roost.

The spectral bat uses large, curved claws on each of its thumbs to hook onto prey and its teeth — 34 of them, with four upper and four lower incisors — to feast.

It's also attracted to the calls of bats tangled in mist nets; making easy prey of the poor trapped creatures before researchers can collect them.

The spectral bat lives in dense tropical forests throughout Central America and northern South America, typically in the lowlands and often near a river or stream.

It roosts in tree hollows, caves, or the ruins of Mayan temples. A roost usually contains a monogamously mated pair and their two or three children.

Most male bats don't participate in raising young — out of all the bat species, there are only two in which males are known to care for their young. One of them is the spectral bat.

While one parent is out hunting, the other always remains in the nest to watch over the pups. When the hunter returns, he/she shares the meal.

As spectral bats settle to sleep, the male enwraps his family in his large, leathery wings.

This species is considered 'near threatened' by the IUCN, due to habitat destruction and a low population density.