Tooth-billed Pigeon | All good Facts That You Want To Know 2021

 

Samoa is home to a big pigeon known as the manumea (Didunculus strigirostris), the Tooth-billed pigeon in certain circles. It is the only species of the genus Didunculus that is still alive today. According to phylogenetic analyses, it is the most basic living member of the group Columbidae and the ancestor of all other extant lineage members. Several archaeological sites in Tonga have revealed subfossil remnants of a similar ancient species, the Tongan Tooth-billed pigeon (Didunculus placopedetes), considered extinct. This bird is Samoa’s national bird, and it is shown on the country’s 20 bills and 50 sene pieces from the 2008/2011 series of coins.

Description Of Tooth-billed Pigeon:

Approximately 31 cm in length, the tooth-billed pigeon is a medium-sized, black pigeon with crimson feet and red exposed skin around the eye. With a little blue-green iridescence on the underparts, the head and neck are greyish. The tail, wings-coverts, and tertials are rufous chestnut, while the remaining remiges are blackish.

With tooth-like protrusion on the lower jaw, it sports a big bright red bill curled and hooked at the ends. In appearance, both sexes of the Tooth-billed pigeon are similar. However, the juvenile has a duller appearance with a browner head and a black bill, with the base of the bill being a light orange color.

It is uncommon – possibly unique – among members of the Columbiformes in that it drinks by scooping water up with its bill, in the way of the vast majority of bird species, rather than sucking it up with the tongue like a straw, as is the case with the majority of bird species.

Taxonomy And Systematics Of Tooth-billed Pigeon:

Taxonomy and systematics are two terms that are used to describe the study of classification and organization. The United States Exploring Expedition most likely discovered the species under the command of Commander Wilkes in October or November 1839. It was announced by Hugh Edwin Strickland in September 1844 that the bird had been discovered by Mr. Titian Peale, the expedition’s naturalist, and that it was one of the expedition’s “rare specimens.”

Although the genus of Tooth-billed pigeon name Gnathodon strigirostris was already used for a mollusk at the official description, William Jardine, published it in the Annals of Natural History, volume xvi, page 175, plate 9, using the name Gnathodon strigirostris.

Although it does not have a living cousin, it has been proven to be genetically related to the Dodo, and the genus name Didunculus translates as “small dodo.”

Sir Richard Owen proposed the term “dodlet” for the English version of the word. There has been speculation about a possible connection to parrots based on the jaw and tongue anatomy and the bill’s parrot-like shape. However, these characteristics have more to do with its specialized diet than with any actual kinship.

In the following cladogram, by Shapiro and colleagues (2002), the Tooth-billed pigeon is shown as the basal member of the clade, with the closest relatives within Columbidae, which is a subclade composed mostly of ground-dwelling island endemics, the Dodo being the most notable member.

Similarly, constructed cladograms were published in 2007; however, they differed mainly in the location of Goura and Didunculus and the inclusion of the pheasant pigeon and thick-billed ground pigeon at the base of the clade, which was previously excluded.

Geographical Distribution And Habitat of Tooth-billed Pigeon:

The Tooth-billed pigeon is restricted to the unspoiled woods of Samoa, which is located in the Pacific. The Central Savaii Rainforest, Tafua Preserve, Fagaloa Bay – Uafato Tiavea Conservation Zone on Upolu Island, and Nu’ulua Island are all good places to look for the tooth-billed pigeon in Samoa. The species’ ecology and biology are unknown, although it is thought to feed on the fruits of Dysoxylum, a tree from the mahogany family, which it does not consume. Chicks are said to be restricted to the forest floor, according to manuscripts from the 1800s. However, the exact placement of the nests (whether in a tree or on the ground) has yet to be determined.

Status Of Tooth-billed Pigeon:

The Tooth-billed pigeon is listed as critically endangered on the International Union for Conservation of Nature’s Red List of Threatened Species because of ongoing habitat loss, a limited range, a small population size, hunting, and occasional cyclones, as well as the potential impact of introduced species such as pigs, dogs, rats, and cats.

According to surveys, numbers are critical, with just 70 to 380 individuals surviving in the wild at any one time. There is presently no captive population of this species. There had been no recent sightings of juveniles until a solitary youngster was discovered in the lowlands of Savaii in 2013 during a study conducted by the Samoan Ministry of Natural Resources and the Environment. Because of the high chick mortality rate, the reported population is probably composed mostly of older adult birds.

Actions to preserve this species will most likely require conservation education to decrease hunting danger and an understanding of the biology of the population and the factors contributing to its present decline, among other things. The management of rat and cat populations, preventing further deforestation, and the loss of old-growth forests are expected to be important. During a forest study on the island of Savaii in 2020, the bird was both heard and sighted for the first time.

Threats For Tooth-billed Pigeon:

Hunters still pose a significant threat, particularly when the common Pacific Imperial-Pigeon Ducula Pacifica is the primary target (Collar 2015, Serra et al. 2017, Stirnemann et al. 2018). The rate of homicide was estimated to have been about 400-500 victims every year by Beichle (1982).

This rate might have continued through the 1980s (Baummannet al., 2003). Researchers interviewed 30 hunters between 2015 and 2016, and 30% reported they accidentally killed at least one Tooth-billed pigeon, including two in 2016 (Stirnemann et al. 2018). Experiencing cyclones is likely to increase rat and cat depredation (Black Rattus rattus and Pacific Rattus exulans) (Collar 2015, Serra et al. 2017).

The Ministry of Natural Resources and Environment (2006) has noted a significant loss of habitat due to habitat destruction due to human activity. As a result of Cyclone Evan in 2012, natural habitat was lost, and fruiting trees were lost. This led to exotic plants causing the recovery of native trees to be weakened (Ministry of Natural Resources and Environment 2006).