The vampire ground finch (''Geospiza septentrionalis'') is a small

bird Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...

native to the

Galápagos Islands The Galápagos Islands (Spanish: , , ) are an archipelago of volcanic islands. They are distributed on each side of the equator in the Pacific Ocean, surrounding the centre of the Western Hemisphere, and are part of the Republic of Ecuador ...

. It was considered a very distinct

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...

of the

sharp-beaked ground finch The sharp-beaked ground finch (''Geospiza difficilis'') is a species of bird in the Darwin's finch group of the tanager family Thraupidae. It is classified as a least-concern species by the International Union for Conservation of Nature and it is ...

(''Geospiza difficilis'')

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

Wolf The wolf (''Canis lupus''; : wolves), also known as the gray wolf or grey wolf, is a large canine native to Eurasia and North America. More than thirty subspecies of ''Canis lupus'' have been recognized, and gray wolves, as popularly u ...

and

Darwin Island Darwin Island (Spanish: ''Isla Darwin'') is among the smallest in the Galápagos Archipelago with an area of just . It is named in honour of English scientist Charles Darwin. With no dry landing sites, Darwin Island's main attractions are fo ...

s.Grant, Peter R.; Grant, B. Rosemary & Petren, Kenneth (2000). The allopatric phase of speciation: the sharp-beaked ground finch (''Geospiza difficilis'') on the Galápagos islands. '' Biol. J. Linn. Soc.'' 69(3): 287–317. The

International Ornithologists' Union The International Ornithologists' Union, formerly known as the International Ornithological Committee, is a group of about 200 international ornithologists, and is responsible for the International Ornithological Congress and other international ...

has split the species supported by strong genetic evidence that they are not closely related, and divergences in morphology and song. Other taxonomic authorities still consider it

conspecific Biological specificity is the tendency of a characteristic such as a behavior or a biochemical variation to occur in a particular species. Biochemist Linus Pauling stated that "Biological specificity is the set of characteristics of living organ ...

Description

The vampire finch is

sexually dimorphic Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...

as typical for its

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

, with the males being primarily black and the females grey with brown streaks. It has a lilting song on Wolf, a buzzing song on Darwin, and whistling calls on both islands; only on Wolf, a drawn-out, buzzing call is also uttered.

Ecology

This bird is most famous for its unusual diet. When alternative sources are scarce the vampire finch occasionally feeds by drinking the blood of other birds, chiefly the

Nazca Nazca (; sometimes spelled Nasca; qu, Naska) is a city and system of valleys on the southern coast of Peru. It is also the name of the largest existing town in the Nazca Province. The name is derived from the Nazca culture, which flourished in ...

and blue-footed boobies, pecking at their skin with their sharp beaks until blood is drawn.Schluter, Dolph & Grant, Peter R. (1984). Ecological Correlates of Morphological Evolution in a Darwin's Finch, ''Geospiza difficilis''. ''

Evolution Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...

'' 38(4): 856-869. (HTML abstract and first page image) Curiously, the boobies do not offer much resistance against this. It has been theorized that this behavior evolved from the pecking behavior that the finch used to clean

parasite Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has ...

s from the plumage of the booby. The finches also feed on eggs, stealing them just after they are laid and rolling them (by pushing with their legs and using their beak as a pivot) into rocks until they break. Finally guano and leftover fish from other predators additionally serve as diet options. More conventionally for birds, but still unusual among ''Geospiza,'' they also take

nectar Nectar is a sugar-rich liquid produced by plants in glands called nectaries or nectarines, either within the flowers with which it attracts pollinating animals, or by extrafloral nectaries, which provide a nutrient source to animal mutualists ...

from

Galápagos prickly pear ''Opuntia galapageia'' is a species of cactus. It is endemic to the Galápagos Islands, part of Ecuador. Forms occurring on different islands have been treated as separate species and subtaxa of these species. ''Opuntia echios'', ''Opuntia heller ...

(''Opuntia echios'' var. ''gigantea'') flowers at least on Wolf Island. The reason for these peculiar feeding habits is the lack of

fresh water Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. Although the term specifically excludes seawater and brackish water, it does include ...

on these birds' home islands. Nonetheless, the mainstay of their diet is made up from seeds and

invertebrates Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...

as in their congeners.

Conservation

The vampire finch is classified as vulnerable by the

IUCN The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

based on its very restricted distribution and the impact of invasive species in its habitat.

References

External links

* {{Taxonbar, from1=Q1054264, from2=Q55118761 Geospiza Endemic birds of the Galápagos Islands Hematophages Parasitic vertebrates Birds described in 1899 Taxa named by Walter Rothschild Taxa named by Ernst Hartert