Diet , one of the spectral bat's primary food sources The spectral bat is exclusively
carnivorous, consuming
birds,
rodents, and other species of
bat. Additionally, it consumes some
insects such as
beetles. It was once thought to supplement its diet with fruit, but a captive pair refused to eat any fruit over a 5-year period.
Doves and
cuckoos are frequently consumed—they represented over half the prey items documented in the Costa Rican study. Some prey species such as cuckoos,
trogons, and
motmots are known to have a strong odor, leading Vehrencamp et al. to hypothesize that spectral bats may rely on scent to locate prey. It also prefers prey that roost in groups, which may aid in detection. The
groove-billed ani, which both has a strong smell and roosts in groups, is a particularly common prey item, representing approximately 24-26 of the 86 prey items identified in the study. Other species identified included the
orange-fronted parakeet,
orange-chinned parakeet,
rufous-naped wren,
streak-backed oriole, and
scissor-tailed flycatcher. The largest prey species identified was the
white-tipped dove, which at , weighs almost as much as spectral bats. Because its prey items can be so large, it may only need to consume one bird every two or three nights to meet its caloric requirements.
Foraging spectral bat "consuming" a mouse The spectral bat uses
echolocation to navigate, creating short pulses of
ultrasound at relatively low frequencies; its echolocation characteristics are suited for maneuvering around obstacles while flying low to the ground. It kills its prey by delivering a forceful bite to the skull. Relative to its size, its
bite force is stronger than any
Carnivoran. It has been recorded as being attracted to the distress calls of smaller bats while hunting. In a study of the wing
morphology of 51
Neotropical bat species, the spectral bat had the lowest
wing loading (body mass to wing area ratio) at 20.05. Low wing loading is
advantageous for carnivorous bats because it allows them to pick up prey items from the ground and fly with them. Its wing structure allows it to take flight in confined spaces and to carry heavy prey items, despite the bat's size. Males will carry prey back to their roosts to provision females and their pup. Males have relatively small
testes—as a monogamous species, there is not generally
sperm competition, so males can save energy by producing less sperm. It is a
seasonal breeder, with females giving birth at the end of the dry season or the beginning of the rainy season. The mother is reportedly very attentive and gentle with her offspring. The male is often in attendance as well and will frequently sleep with both the female and their young completely wrapped up in his wings. Spectral bats roost independently or in small colonies of up to five individuals in hollow trees. An examination of one colony of five individuals consisted of an adult male and female, a nursing pup, and a juvenile male and female. The juvenile male was estimated to be six months old; he was presumed to be the older offspring of the adults, while the female was also possibly their offspring. Though it was initially believed to only roost in trees, it was first documented using a cave as a roost in 2008. Its average lifespan is unknown; however, it is believed that the same individual roosted in a cave from 2008 until at least 2016 based on a unique ear pigmentation, making lifespans of at least 8 years possible. In captivity, one adult individual of uncertain initial age was maintained for 5.5 years.{{cite journal|doi=10.1515/mammalia-2016-0038|title=Long-term cave roosting in the spectral bat (
Vampyrum spectrum)|journal=Mammalia|volume=81|issue=5|year=2017|last1=Dinets ==Conservation==