This discussion was first published as part of the 2012 Red List update, but remains open for comment to enable reassessment in 2013.
BirdLife species factsheet for Tooth-billed Pigeon
Tooth-billed Pigeon Didunculus strigirostris has been listed as Endangered on the IUCN Red List since 2000 because its numbers were believed to have declined rapidly to fewer than 2,500 mature individuals following the effects of cyclones on its native Samoan forest during the 1990s. An eleven month survey in 2005-2006 reported the species from only ten locations, and the population was estimated to number only a few hundred , although the remote and largely intact uplands of Savai’i remain largely unsurveyed (MNRE 2006). It is unclear whether, since 2006, the species has declined further and new information is urgently required to clarify recent records of Tooth-billed Pigeon. At the same time, if the apparent paucity of recent records reflects a further population decline in recent years, a conservative outlook suggests its global population may have been reduced to fewer than 250 mature individuals, qualifying the species as Critically Endangered under criterion C2a with an on-going decline in progress. Comments and recent records are invited.
Reference:
Ministry of Natural Resources & Environment (MNRE), Samoa (2006) Recovery plan for the Manumea or Tooth-billed Pigeon Didunculus strigirostris. Government of Samoa.
Related posts:
During my1.7 years of field work in Samoa (2010-2011) I have spent large periods of time in the Samoan forest. During this time I have had two sightings of the Manumea and heard it call.
Infomation from local hunters suggest that whilst they saw the bird a few times a year previously, in the last two years many hunters have not seen a Manumea dispite continuing to use the forest regularly. This suggests a strong decline in numbers on Upolu.
Field Surveys for the recent IBA report recorded the following -
6 birds at 5 out of 9 point count locations at Easter Upolu IBA in April, 2009. Not clear whether these birds were seen or heard.
6 birds at 3 out of 9 point count locations in July 2009, on Nuutele, Aleipata. Point counts on 3 consecutive days, birds recorded on 2 of the 3 counts at each of 3 locations. Birds were reported as heard, only, at 1 of the locations, and on 1 occasion at a second location.
I believe that 1 bird was reported on Nuutele in 2010, but am not aware of any records from Easter Upolu. I don’t think that Rebecca saw her birds in either of these locations.
The bird appears to be still present, but in very low numbers at a number of sites on Upolu. And, as Rebecca indicates, there is a perception that numbers have declined recently. We don’t know why.
We don’t know the situation on Savai’i, but if numbers have declined there in the way reported on Upolu then there is a strong chance that the population has declined t obelow 250 birds. A planned survey in2012 of Savai’i uplands will provide more information from here.
The following comments were sent by Derek Scott:
I visited Western Samoa briefly in July 1990, and spent a morning in the highlands (around Lake Lanoto’o) looking for Tooth-billed Pigeon, but without success. A major cyclone struck Western Samoa in February 1990, only six months before my visit, and this had devastated vast swathes of the native forest. At least 95% of the tall trees had been blown down in the area that I visited, and I guess that the pigeon had suffered badly.
I sighted two birds in June one flying and one sitring in a tree and then calling. They appear to be moving around and to be more vocal in this period suggesting this maybe a good time to survey the species. A survey is being undertaken likely to be under taken in late May in Savaii 2012.
Cyclone Evan (Dec 2012) is likely to be further impacting the survival of this species since large numbers of native trees have fallen on both the South side and in the Apia area.