Geospiza difficilis septentrionalis, also known as the Vampire Finch, is a small bird species with a highly unusual diet - the blood of other birds.

Found exclusively on two tiny islands in the Galapagos archipelago - Darwin and Wolf - vampire finches are a subspecies of sharp-beaked finches. Despite their relatively small size and seemingly harmless demeanor, they possess a sharp beak used for piercing various fruits and cactus pods. The name 'vampire finch' originates from their peculiar habit of pecking at the skin of larger bird species and feeding on their blood whenever alternative food sources are scarce.

Nazca boobies and Blue-footed boobies are the primary victims of vampire finches. Interestingly, despite being much larger than their attackers, these seabirds rarely resist. Experts believe that this unusual feeding behavior evolved from a common practice observed in many known finch species - pecking at parasites on the feathers and skin of larger birds. Essentially, Nazca and Blue-footed boobies do not perceive the vampire finch's feeding habits as a threat.

Although the exact evolution of how vampire finches developed this peculiar eating behavior remains unknown, it is believed that over many eras, excessive pecking into the skin and causing bleeding in other seabirds during their parasite-eating practices led them to adapt to consuming blood as a supplementary food source.

Feeding on the blood of animals and other bird species is an extremely rare behavior in birds, and vampire finches are considered a uniquely adapted phenomenon in the ecosystem of Darwin and Wolf Islands.


References: Odditycentral; ZME; AFP