Mammals
Hammer-Headed Bat
Hypsignathus monstrosus · also called hammer-headed fruit bat, big-lipped bat
At a nighttime gathering deep in the rainforest, male hammer-headed bats line up along the canopy and honk loudly through an oversized larynx, each hoping his call carries far enough to draw in a passing female of Africa’s largest bat species.
Overview
The hammer-headed bat, Hypsignathus monstrosus, is the largest bat species in Africa, native to rainforest and wetland habitat across a range spanning much of Central and West Africa. Its extreme sexual dimorphism, males’ dramatically enlarged head and vocal apparatus, and lek-based mating displays make it one of the more visually and behaviourally striking fruit bats found anywhere in the world.
A face built entirely for sound
The male hammer-headed bat’s oversized head and snout exist almost entirely to house an enlarged larynx, an anatomical trade-off that produces one of the loudest, strangest mating calls of any bat in exchange for a face few would call conventionally attractive.
Status
Least Concern, remaining present across suitable rainforest and wetland habitat throughout Central and West Africa, though detailed population trends are not well documented.
Hammer-Headed Bat: common questions
Why do male hammer-headed bats look so different from females?
A male of this species has a dramatically enlarged head, snout, and larynx compared with females, an exaggerated feature that houses the vocal apparatus used to produce the loud honking calls males rely on to attract mates at communal display grounds.
How do hammer-headed bats attract mates?
Males of this species gather at traditional nightly display grounds called leks, where each individual repeatedly produces loud, low-pitched honking calls to attract passing females, a mating system shared with relatively few other mammal species.
How big is the hammer-headed bat?
This species is the largest bat found anywhere in Africa, with males considerably larger and heavier than females, contributing to one of the more extreme cases of size and shape difference between the sexes found among bats worldwide.
What does the hammer-headed bat eat?
This species feeds primarily on fruit such as figs, located by scent and sight while foraging widely across the rainforest canopy at night, occasionally travelling considerable distances between fruiting trees.