Justification of Red List Category
This species is endemic to one tiny island where, despite its very small population, it was previously considered secure. However, since the first observation of black rats on the island in 2000, it has declined extremely rapidly and the current population is now estimated to be extremely low. It hence qualifies as Critically Endangered.
The population was estimated to number 67 individuals in 2009 (T. Ghestemme in litt. 2010). Based on a 30% decline in territories since this estimate, it is now thought to number c. 50 birds, roughly equivalent to 33 mature individuals (T. Ghestemme in litt. 2012).
In February 2000 the total population was estimated at a few hundred pairs (Thibault and Meyer 2001, Gouni 2006), but by 2011 the total population was estimated to have fallen to as low as 50 individuals (Anon. 2010, T. Ghestemme in litt. 2010, 2012). Since the first observation of Black Rats Rattus rattus on Fatu Hiva in 2000 there has been an extremely rapid population decline equating to over 90% over three generations (21 years). Recent predator control has reduced the rate of territory loss from 60% in 2007-2009, to 30% in 2009-2011 (Ghestemme 2012). Between 2010 and 2012, the population started to increase slowly, with the number of adult individuals in protected areas increasing from 27 to 36 (Ghestemme 2013).
Pomarea whitneyi is endemic to Fatu Hiva in the Marquesas Islands, French Polynesia. In 1975, the population was estimated at several hundred pairs and, in 1990, it was still common (Holyoak and Thibault 1984, Seitre and Seitre 1991). In 2000 the total population was estimated at 400-1,000 individuals (Thibault and Meyer 2001, Gouni 2006). Unlike in 1975, no birds were observed in the groves of mango on the slopes and ridges up the Omoa Valley, and the lack of adults with immatures indicated low breeding success (Thibault and Meyer 2001). Repeat visits in 2003 and 2006 only found the species using three from eight potentially suitable valleys above Omoa, and just one from seven near Hanavave. Furthermore, the encounter rate during surveys declined from 0.35 individuals per point count in 2003 to 0.23 individuals in 2006, a decline of 35% in the number of monarchs detected during that period (Gouni 2006). These catastrophic declines continued, with a five-month survey in 2009 finding only 0.11 individuals per point count (T. Ghestemme in litt. 2010), and totals of 13 territories and 41 birds found. The total population in 2009 was estimated to be as low as 67 individuals (Le Barh 2009, T. Ghestemme in litt. 2010). In 2011, an estimated 65% of the birds were restricted to a region of 2 km² in the Omoa Valley (Ghestemme et al. 2011). In recent years, the rate of decline has decreased and some juveniles have fledged: 26 juveniles have fledged across eight years, including six in 2017 (SOP-Manu 2017). The number of breeding individuals remains extremely low, with only four pairs thought to be breeding in 2017 (SOP-Manu 2017).
It occurs in dense, native forest from 50 m to 700 m, with some non-breeding birds found up to 775 m on a crest below the highest summit on Mt Touaouoho in native wet forest (Thibault and Meyer 2001). It feeds on insects (e.g. Coleoptera), spiders and seeds (Holyoak and Thibault 1984). Nests are placed in a thin tree fork (Anon. 2010).
Fatu Hiva is a relatively well preserved, well forested island (with no overgrazing or destruction of vegetation by fire). Black Rat Rattus rattus was observed for the first time on the island in February 2000 (Thibault and Meyer 2000) and identified as a serious threat as its presence is strongly correlated with the decline and extinction of monarch populations (Thibault et al. 2002), rats already appear to have caused an extremely rapid population decline and represent the principal threat to the species (Gouni 2006). Their density remains very high (T. Ghestemme in litt. 2012). Successful recent breeding has only very rarely been noted except in areas cleared of rats; elsewhere the lack of juveniles indicates a rapidly ageing population, with at least 4 of the 10 protected pairs confirmed as sterile in 2011 (Anon. 2010, Ghestemme et al. 2011). Feral cats Felis catus also appear to be a significant threat to the species as two adults were sighted without tails, typically a sign of a cat predation attempt. Cats are apparently released in agricultural areas near to where the monarch is found (T. Ghestemme in litt. 2010), and have been found in every part of the island (T. Ghestemme in litt. 2012). They are presumably capable of impacting the monarch even in areas where rats have been cleared (Anon. 2010). Bush fires during the dry season, forest clearance and the establishment of non-regulated agricultural tracks in the species's habitat are also increasing threats (Raust 2010, T. Ghestemme in litt. 2012).
Conservation and Research Actions Underway
The population has been regularly checked since the 1970s (Holyoak and Thibault 1984, Thibault and Meyer 2001) and its reproductive success is being monitored (Ghestemme 2016). Conservation efforts have increased owing to the recent rapid decline in the population. Rat control has been on-going at accessible territories since 2008 (SOP-Manu 2016). It focuses on the Omoa Valley (T. Ghestemme in litt. 2012), but work is being extended gradually to additional areas (A. Gouni in litt. 2007, T. Ghestemme in litt. 2010): in 2011 all known accessible territories (29 individuals in 12 valleys) were being protected against rats, with significant improvements including spreading bait with catapults to reach previously inaccessible areas (Ghestemme et al. 2011). Nests are being protected (SOP-Manu 2017). Feral cat control has been underway since August 2010 (Ghestemme et al. 2011) and a programme is underway to sterilize domestic cats without charge (SOP-Manu 2017). A feasibility study was carried out to assess the suitability of other islands for translocation: without further rat eradications, Rimatara was found to be the only suitable island and due to the small amount of suitable habitat for the Fatu Hiva Monarch, translocation of Tahiti Monarch P. nigra was considered preferable here (Ghestemme et al. 2011, A. Gouni in litt. 2007). The island of Makatea has also been assessed as a suitable translocation site if it is eradicated of rats (Albar et al. 2009). A recovery group, shared with P. nigra, has been established to formulate a conservation strategy (T. Ghestemme in litt. 2010), and a site support group was created in August 2010 (Ghestemme et al. 2011). An awareness campaign is underway, targeted at local people, including schoolchildren, with an aim to educate about the status of the species, and a poster and t-shirt have been produced as part of the process (T. Ghestemme in litt. 2010). SOP-Manu have worked with landowners to raise awareness of the species's conservation and to promote bee-keeping as a sustainable livelihood (SOP-Manu 2016). Population banding began in late 2009, with nine birds colour-banded by the end of 2011 (Ghestemme et al. 2011, T. Ghestemme in litt. 2010, 2012). A new species action plan is being formulated (Ghestemme 2016). The Ministry of Health and Environment is working to reduce bushfires during times of drought and increasing regulation of agricultural tracks that would impact the species's habitat (Raust 2010).
Conservation and Research Actions Proposed
Continue and improve rat control in areas where this work is already ongoing, and expand control to other areas (Thibault and Meyer 2000, Thibault et al. 2002, T. Ghestemme in litt. 2010). Examine the feasibility of complete rat eradication. Produce a more detailed action plan (T. Ghestemme in litt. 2012). Conduct surveys elsewhere on the island using the same methodologies and continue to monitor the known population through banding (Gouni 2006, T. Ghestemme in litt. 2010). Consider translocation, either to another island or by creating another, larger controlled area in an accessible part of Fatu Hiva which would allow birds to be translocated to it from valleys where protection is impossible (Anon. 2010). Establish a captive breeding programme to aid in establishment of new populations/supplement existing populations. Continue the public awareness programme (Gouni 2006, T. Ghestemme in litt. 2010). Continue and extend cat control and assess its effect on the species (T. Ghestemme in litt. 2010).
19 cm. Large flycatcher with plush-like feathers on forehead. Adult glossy purplish-black. Immature dull brown above, redder on wings, buffy-white below with rufous tinges to face, neck, and sides of breast. Voice Typical call described as cri-ri-a-rik, similar to the shrill meow of a cat whose tail has been stepped on. Alarm call is a nervous ki ki ki.
Text account compilers
Bird, J., Khwaja, N., O'Brien, A., Derhé, M., Shutes, S., Stattersfield, A., Symes, A., Calvert, R., Wright, L, Hermes, C., Wheatley, H.
Ghestemme, T. & Gouni, A.
BirdLife International (2021) Species factsheet: Pomarea whitneyi. Downloaded from http://www.birdlife.org on 22/10/2021. Recommended citation for factsheets for more than one species: BirdLife International (2021) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 22/10/2021.