Species of bird
Not to be confused with
Manuma
.
The
tooth-billed pigeon
(
Didunculus strigirostris
), also known as the
manumea
, is a large pigeon found only in
Samoa
. It is the
only living
species
of
genus
Didunculus
. A related
extinct
species, the
Tongan tooth-billed pigeon
(
Didunculus placopedetes
), is only known from
subfossil
remains in several archeological sites in
Tonga
.
[2]
[3]
The tooth-billed pigeon is the
national bird
of Samoa and featured on the 20
t?l?
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
[
edit
]
The tooth-billed pigeon is a medium-sized, approximately 31 cm 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. Both sexes are similar, but the
juvenile
is duller with a browner head, with a black bill with only the base a pale orange.
[4]
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.
[5]
Taxonomy and systematics
[
edit
]
The species was probably found in 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.
[6]
It has no close living relative, but it has been shown to be genetically close to the
dodo
,
[7]
and the genus name
Didunculus
means "little dodo".
[8]
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.
[7]
|
|
|
|
|
Didunculus strigirostris
(
tooth-billed pigeon
)
|
|
|
|
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.
[9]
Distribution and habitat
[
edit
]
The tooth-billed pigeon is confined to undisturbed forests of
Samoa
in the
Pacific
. Natural habitats for the tooth-billed pigeon in Samoa include the
Central Savai'i Rainforest
,
Tafua Preserve
,
Fagaloa Bay ? Uafato Tiavea Conservation Zone
on
Upolu Island
, and
Nu'ulua
island. Little is known about the ecology and biology of the species but it is believed to feed on the fruits of
Dysoxylum
, a tree in the
mahogany
family. Manuscripts from the 1800s suggest chicks are confined to the forest floor. However the location of nests (in a tree or on the ground) is still unconfirmed.
Status
[
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]
Because of ongoing habitat loss, limited range, small population size, hunting and occasional cyclones as well as the likely impact of introduced species such as pigs, dogs, rats and cats, the tooth-billed pigeon is evaluated as
critically endangered
on the
IUCN Red List
of Threatened Species. Surveys suggest numbers are critical and that 70 to 380 individuals survive in the wild, and there is currently no captive population.
[10]
No juveniles had been sighted during any recent surveys until the 2013 sighting of a single juvenile in the lowlands of Savaii during a survey of the Samoan Ministry of Natural Resources and the Environment.
[1]
It is highly likely that chick mortality is high and the observed population are an aged population of adult birds. Actions to save this species will likely require conservation education to reduce hunting risk, and knowledge of the biology of the population and the reasons behind the current decline. Population control for rats and cats is likely to be critical, as is continuing deforestation and disappearance of old-growth forests.
[1]
In 2020 the bird was both heard and seen during a survey of forests on
Savai'i
.
[11]
References
[
edit
]
- ^
a
b
c
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
.
- ^
Hume, J.P.; Walters, M. (2012).
Extinct Birds
. London: T & AD Poyser. p. 544.
ISBN
978-1-4081-5725-1
.
- ^
Tyrberg, T. (2009). "Holocene avian extinctions". In Turvey, S.T. (ed.).
Holocene extinctions
. Oxford, UK: Oxford University Press. p.
352
.
ISBN
978-0-19-953509-5
.
- ^
Gibbs, David; Barnes, Eustace; Cox, John (2001).
Pigeons and doves: a guide to the pigeons and doves of the world
. A&C Black.
- ^
Wickler, W. (1961). Uber die Stammesgeschichte und den taxonomischen Wert einiger Verhaltensweisen der Vogel.
Zeitschrift fur Tierpsychologie, 18
, 320-342.
https://dx.doi.org/10.1111/j.1439-0310.1961.tb00423.x
- ^
Newton, Alfred (1893?1896).
A Dictionary of Birds
. London: Adam & Charles Black. p.
154
.
- ^
a
b
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
- ^
Rauzon, Mark J. (2007).
"Island restoration: Exploring the past, anticipating the future"
(PDF)
.
Marine Ornithology
.
35
(2): 97?107.
- ^
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
.
- ^
Extinction warning: racing to save the little dodo from its cousin's fate
- ^
Sapeer Mayron (25 August 2020).
"Near-extinct manumea spotted in Savai'i"
. Samoa Observer
. Retrieved
5 August
2021
.
External links
[
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]