Penguins have a variety of ennemies both on on land and at sea. This i
s the first account of vampire bats (Desmodus rotundus) preying on juv
enile Humboldt Penguins (Spheniscus humboldti). Because of the nightly
drain of blood by vampires, and because vampires transmit diseases fr
om one prey species to another, this form of predation may be an impor
tant mortality factor.