Tooth-billed pigeon

Tooth-billed pigeon
Mounted specimen at the Naturalis Biodiversity Center
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Columbiformes
Family: Columbidae
Genus: Didunculus
Species:
D. strigirostris
Binomial name
Didunculus strigirostris
(Jardine, 1845)

The tooth-billed pigeon (Didunculus strigirostris), also known as the manumea, is a large pigeon endemic to Samoa. It is the only living species of genus Didunculus. The tooth-billed pigeon is the national bird of Samoa and featured on the 20 tālā bills and the 50 sene pieces of the 2008/2011 series. Native only to Samoa's primary rainforest, it is considered to be endangered, with only a few hundred individuals thought to remain in existence.

Description

Illustration by John Gould (probably from stuffed specimens)
Illustration in habitat by Gustav Mützel

The tooth-billed pigeon is a medium-sized, approximately 31 centimetres (12 in) long, dark pigeon with reddish feet and red bare skin around the eye. The underparts, head and neck are greyish with a slight blue-green iridescence, and the tail, wings-coverts and tertials are rufous chestnut, while the remaining remiges are blackish. It has a large, curved, and hooked bright red bill, with tooth-like projections on the lower mandible which let them act as seed dispensers. The sexes are similar in appearance, but the juvenile is duller, with a browner head, and a black bill with pale orange at the base. Behaviourally, it is unusual – perhaps unique among members of Columbiformes in drinking by scooping water up in its bill, in the manner of the great majority of bird species, rather than sucking it up using the tongue as a straw.

Taxonomy and systematics

The species was likely discovered on October or November 1839, by the United States' Exploring Expedition under Commander Wilkes. The discovery of the bird was announced by Hugh Edwin Strickland in September 1844 as being among the rarities obtained by Mr. Titian Peale, the naturalist of the expedition. The formal description was made by William Jardine (Ann. Nat. Hist. xvi. p. 175, plate 9), under the name of Gnathodon strigirostris, although that genus name was already in use for a mollusc.

It has no close living relative, but it has been shown to be genetically close to the dodo, and the genus name Didunculus means "little dodo". the English name of dodlet was suggested by Sir Richard Owen. The jaw and tongue structure, and the superficially parrotlike bill have suggested a relationship to the parrots, but these features have arisen from its specialised diet rather than any real relationship.

The following cladogram, from Shapiro and colleagues (2002), shows the tooth-billed pigeon as the basal member of the clade and closest relationships within Columbidae, a clade consisting of generally ground-dwelling island endemics of which the Dodo is the most prominent.

Didunculus strigirostris (tooth-billed pigeon)

Goura victoria (Victoria crowned pigeon)

Caloenas nicobarica (Nicobar pigeon)

†Pezophaps solitaria (Rodrigues solitaire)

†Raphus cucullatus (dodo)

A similar cladogram was published in 2007, differing only in the inverted placement of Goura and Didunculus, as well as in the inclusion of the pheasant pigeon and the thick-billed ground pigeon at the base of the clade.

Distribution and habitat

The tooth-billed pigeon is confined to undisturbed forests of both the islands of Samoa in the Pacific. It is only found on three islands, Savai'i, Upolu, and Nu'utele. It lives away from sea level on its main food source, the fruits of two species of Dysoxylum, a tree in the mahogany family, though baby chicks are unable to do so.

Threats

Live specimen, 1901

The Tooth billed pigeon is critically endangered by the IUCN Red List. The bird is threatened by habitat destruction, hunting, and invasive animals. In the 1990s, the population of the tooth billed pigeon was 7,000. Two major cyclones destroyed most of its natural habitat, so the population decreased to 2500. A recovery search in 2006 then documented a population of 500. It is suggested that the population of mature individuals is now under 200. The bird was used as a source of food, as well as its feathers used to make fine mats. The last confirmed photo was of a juvenile in 2013.

In 2020 the bird was both heard and seen during a survey of forests on Savai'i.

References

  1. 1 2 BirdLife International (2019) [amended version of 2018 assessment]. "Didunculus strigirostris". IUCN Red List of Threatened Species. 2019 e.T22691890A156841404. doi:10.2305/IUCN.UK.2018-2.RLTS.T22691890A156841404.en. Retrieved 12 November 2021.
  2. 1 2 Gibbs 2010, p. 585.
  3. ↑ Sippel, Annika (15 July 2024). "The Sāmoan Manumea – how can museums help to protect this national treasure?". Te Papa Blog. Archived from the original on 5 August 2024. Retrieved 14 August 2024.
  4. ↑ Wickler, W. (1961). Über die Stammesgeschichte und den taxonomischen Wert einiger Verhaltensweisen der Vögel. Zeitschrift für Tierpsychologie, 18, 320-342. https://dx.doi.org/10.1111/j.1439-0310.1961.tb00423.x
  5. ↑ Newton, Alfred (1893–1896). A Dictionary of Birds. London: Adam & Charles Black. p. 154.
  6. 1 2 Shapiro, B.; Sibthorpe, D.; Rambaut, A.; Austin, J.; Wragg, G. M.; Bininda-Emonds, O. R. P.; Lee, P. L. M.; Cooper, A. (2002). "Flight of the Dodo" (PDF). Science. 295 (5560): 1683. doi:10.1126/science.295.5560.1683. PMID 11872833. Supplementary information
  7. ↑ Rauzon, Mark J. (2007). "Island restoration: Exploring the past, anticipating the future" (PDF). Marine Ornithology. 35 (2): 97–107.
  8. ↑ "Dodlet - The Tooth Billed Pigeon". www.thewonderofbirds.com. Retrieved 2026-10-11.
  9. ↑ Gibbs 2010, p. 14.
  10. ↑ Pereira, S. L.; Johnson, K. P.; Clayton, D. H.; Baker, A. J. (2007). "Mitochondrial and nuclear DNA sequences support a Cretaceous origin of Columbiformes and a dispersal-driven radiation in the Paleogene". Systematic Biology. 56 (4): 656–672. doi:10.1080/10635150701549672. PMID 17661233.
  11. ↑ Gibbs 2010, p. 584.
  12. 1 2 3 4 Collar, N. J. (2015-08-31). "Natural history and conservation biology of the tooth-billed pigeon (Didunculus strigirostris): a review". Pacific Conservation Biology. 21 (3): 186–199. doi:10.1071/PC14923. ISSN 1038-2097.
  13. ↑ Sapeer Mayron (25 August 2020). "Near-extinct manumea spotted in Savai'i". Samoa Observer. Retrieved 5 August 2021.

Bibliography