Vampire ground finch

Vampire ground finch
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Passeriformes
Family: Thraupidae
Genus: Geospiza
Species:
G. septentrionalis
Binomial name
Geospiza septentrionalis
Synonyms

Geospiza difficilis septentrionalis[2][3]

The Vampire ground finch (Geospiza septentrionalis) or Vampire finch is a small bird native to the Galápagos Islands. A member of the Darwin's finches group, it is known for its unique parasitic behavior of feeding on the blood of other birds. It is endemic to Wolf and Darwin Island. The species was previously considered a very distinct subspecies of the sharp-beaked ground finch (Geospiza difficilis),[2] but the International Ornithologists' Union has split the species based on strong genetic evidence that they are not closely related, and divergences in morphology and song.[4]

Description

The vampire finch is sexually dimorphic as typical for its genus, with the males being primarily black and the females grey with brown streaks. It has a lilting song along with a drawn-out, buzzing call on Wolf, a buzzing song on Darwin, and whistling calls on both islands.[2]

Diet

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 and blue-footed boobies, pecking at their skin with their sharp beaks until blood is drawn.[5][6] The boobies do not offer much resistance against this behavior. It has been theorized that this behavior evolved from the pecking behavior that the finch used to clean parasites from the plumage of the booby.[7] Typically the boobies don't fight back because the interaction is relatively harmless for them and not worth abandoning their nest over. [8] Another reason for not fighting back is that the finches sometimes swarm in multiples which makes it impractical for the single booby to defend itself. [9]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. Guano and leftover fish from other predators additionally serve as diet options.[6]

Vampire ground finches drink more blood during dry seasons when seeds and other prey are scarce, resuming omnivory when the rainy season begins. There were also significant variations in the intestinal microbial community structure between species, with a clear separation between vampire ground finches and other finches. Vampire ground finch birds have intestinal microbial communities rich in peptostreptococcaceae, similar to vampire bats.[10]

More conventionally for birds, but still unusual among Geospiza, they also take nectar from Galápagos prickly pear (Opuntia echios var. gigantea) flowers, at least on Wolf Island.[5] The reason for these peculiar feeding habits is the lack of fresh water on these birds' home islands. Nonetheless, the mainstay of their diet is made up from seeds and invertebrates, as in their congeners.[5]

Conservation

The vampire finch is classified as vulnerable by the IUCN based on its very restricted distribution and the impact of invasive species in its habitat.[1]

A dead Darwin finch that was a host of the Avian vampire fly (Philornis downsi). Notice that the nares of the chick's beak have been widened. This is due to the larvae moving around and sucking the blood and tissues of the baby finch.

Conservation efforts that affect the vampire ground finch typically fall under ecosystem wide protection efforts of all of Darwin's finches on the Galapagos, since all of these finches live in similar habitats and face similar problems often introduced by humans such as invasive parasites, newly introduced predators like cats, climate pressures, and habitat disturbances. [11]

Its approximated that fewer than a 1,000 individuals of the Vampire ground finch are endemic to the Wolf and Darwin islands of the Galapagos. This isolated population makes is vulnerable to potential threats such as the invasive Avian vampire fly (Philornis downsi) and viruses like the Avian pox. [12]

Originally spotted in the Galapagos in 1964, the Avian vampire fly (Philornis downsi) targets nests of Darwin's finches with their parasitic larvae. The Avian vampire fly plants their larvae inside of the chicks nares so that they could feed on the blood and tissues of the chicks, often leading to the nestlings' deaths. [13] So far there have only been recorded instances of this happening to Darwin finches on the Santa Cruz island of the Galapagos which is not inhibited by the Vampire ground finch.[14]

See also

References

  1. ^ a b BirdLife International (2022). "Geospiza septentrionalis". IUCN Red List of Threatened Species. 2022 e.T103815245A182414024. doi:10.2305/IUCN.UK.2022-1.RLTS.T103815245A182414024.en. Retrieved 16 May 2024.
  2. ^ a b c 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. doi:10.1006/bijl.1999.0382
  3. ^ Rothschild, W. and E. Hartert. (1899). A Review of the Ornithology of the Galapagos Islands. With Notes on the Webster-Harris Expedition. Novitates Zoologicae Vol. VI, No. 2, pp. 85-205, 2 plates.
  4. ^ Farrington, Heather; Lawson, Lucinda; Clark, Courtney; Petren, Kenneth (29 July 2014). "The evolutionary history of Darwin's finches: speciation, gene flow, and introgression in a fragmented landscape". Evolution. 68 (10): 2932–2944. doi:10.1111/evo.12484. PMID 24976076. S2CID 205123574.
  5. ^ a b c Schluter, Dolph & Grant, Peter R. (1984). Ecological Correlates of Morphological Evolution in a Darwin's Finch, Geospiza difficilis. Evolution 38(4): 856-869. doi:10.2307/2408396 (HTML abstract and first page image)
  6. ^ a b Michel, Alice J.; Ward, Lewis M.; Goffredi, Shana K.; Dawson, Katherine S.; Baldassarre, Daniel T.; Brenner, Alec; Gotanda, Kiyoko M.; McCormack, John E.; Mullin, Sean W. (2018-09-19). "The gut of the finch: uniqueness of the gut microbiome of the Galápagos vampire finch". Microbiome. 6 (1): 167. Bibcode:2018Micb....6..167M. doi:10.1186/s40168-018-0555-8. ISSN 2049-2618. PMC 6146768. PMID 30231937.
  7. ^ Galef, Bennett G. Jr. (19 August 1990). Bekoff, Marc; Jamieson, Dale (eds.). Interpretation, Intentionality, and Communication. Interpretation and Explanation in the Study of Animal Behavior. Vol. I. Boulder, San Francisco & Oxford: Westview Press. pp. 78. ISBN 978-0-8133-7979-1.
  8. ^ Baldassarre, Daniel; Chaves, Jaime; Gotanda, Kiyoko (2021-01-15). "Vampire finches: how little birds in the Galápagos evolved to drink blood". The Conversation. Retrieved 2026-04-22.
  9. ^ Simon, Matt. "Absurd Creature of the Week: The Tiny Blood-Slurping Bird That Terrorizes the Galapagos". Wired. ISSN 1059-1028. Retrieved 2026-04-22.
  10. ^ Song, Se Jin; Sander, Jon G.; Baldassarre, Daniel T.; Chaves, Jaime A.; Johnson, Nicholas S.; Piaggio, Antoinette J.; Stuckey, Matthew J.; Nováková, Eva; Metcalf, Jessica L.; Chomel, Bruno B.; Aguilar-Setién, Alvaro; Knight, Rob; McKenzie, Valerie J. (2019). "Is there convergence of gut microbes in blood-feeding vertebrates?". Philosophical Transactions of the Royal Society B. 374 (1777): 374(1777). doi:10.1098/rstb.2018.0249. PMC 6560276. PMID 31154984.
  11. ^ "Landbird conservation". Charles Darwin Foundation. Retrieved 2026-04-24.
  12. ^ "Vampire Ground-finch Geospiza septentrionalis Species Factsheet". BirdLife DataZone. Retrieved 2026-04-23.
  13. ^ "Supporting the Control of the Invasive Parasitic Fly Philornis downsi". Galápagos Conservancy. Retrieved 2026-04-23.
  14. ^ Kleindorfer, Sonia; Dudaniec, Rachael Y. (2016-08-23). "Host-parasite ecology, behavior and genetics: a review of the introduced fly parasite Philornis downsi and its Darwin's finch hosts". BMC Zoology. 1 (1): 1. doi:10.1186/s40850-016-0003-9. ISSN 2056-3132.
  • Wikimedia Commons logo Media related to Geospiza septentrionalis at Wikimedia Commons
  • "Vampire Finch". Central Pets. Archived from the original on February 10, 2006. Retrieved Dec 19, 2006.
This article is issued from Wikipedia. The text is available under Creative Commons Attribution-Share Alike 4.0 unless otherwise noted. Additional terms may apply for the media files.