||Megapodius pritchardii Gray, 1864
||Tongan Scrubfowl, Nevafou Megapode, Niaufoou Scrubfowl, Polynesian Scrubfowl, Tongan Megapode
||del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A. and Fishpool, L.D.C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 1: Non-passerines. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.
||38 cm. Medium-sized, brown-and-grey megapode. Mostly brownish-grey, paler on head and neck, browner on back and wings, with short, rounded crest on nape. Feathers of face and throat sparse, allowing red skin to show through. Yellow bill. Yellow to light red legs and feet. Similar spp. Buff-banded Rail Gallirallus philippensis has bold bars and much longer bill. Immature Purple Swamphen Porphyrio porphyrio larger with white undertail-coverts. Feral chickens have prominent tails. Spotless Crake Porzana tabuensis smaller and darker with red eyes and legs. Voice Three-part whistle kway-kwee-krrrr from male, usually uttered in duet with female krrrr. Both male and female can initiate the duet.
|Red List Category & Criteria:
||Dekker, R., Dutson, G., Fakaosi, D., Göth, A., Matevalea, C. & Watling, D.
||Derhé, M., Keane, A., Mahood, S., O'Brien, A., Stattersfield, A., Westrip, J., Dutson, G., Wheatley, H.
This species is classified as Endangered because it has a very small population and a very small range restricted to two tiny islands. Although the population on Fonualei, where it was recently introduced, is potentially increasing the population on Niuafo'ou is suspected to be undergoing a continuing decline, owing to egg harvesting and predation. The potential population size increase on Fonualei may mean that the species warrants downlisting in the near future.
|Previously published Red List assessments:|
- 2016 – Endangered (EN)
- 2012 – Endangered (EN)
- 2008 – Endangered (EN)
- 2004 – Endangered (EN)
- 2000 – Critically Endangered (CR)
- 1996 – Endangered (EN)
- 1994 – Endangered (EN)
- 1988 – Threatened (T)
|Range Description:||Megapodius pritchardii is endemic to Tonga where although fossil evidence indicates it was once widespread, there is now only a remnant population on the island of Niuafo'ou and a re-introduced population on Fonualei. On Niuafo'ou it is concentrated around the inner slopes of the caldera (a large sunken water- and forest-filled crater formed after volcanic activity) and on two cat-free islets in the crater lake. In 1979, the population was estimated at 820 adults (Todd 1983) and, in 1991-1993, at 188-235 pairs occupying 641 ha of 719 ha of suitable habitat (Göth and Vogel 1995). This represents 52-65% of possible carrying capacity, assuming an average of 0.5 pairs per ha (Göth and Vogel 1995). Comparisons between individual sites and interviews with local people had strongly suggested an overall decline (Göth and Vogel 1995). Introductions to the islands of Late and Fonualei have been carried out. A 2003 survey on Fonualei found the species to be common, comprising an estimated 300-500 adult individuals (Watling 2004), but there is no evidence of its continued existence on Late (MEECCDMMIC 2014, R. W. R. J. Dekker in litt. 2003, R. Dekker in litt. 2004). A survey in September 2010 revealed that the population on Niuafo'ou has undergone a dramatic decline in the number of nests at all known nesting grounds, and is now confined to small areas within the caldera. Historically, 27 nests were known from 13 different sites across Niuafo'ou (Goeth unpublished data, in Tilmouth 2010), but during the September 2010 survey only 10 active nests at 7 sites were found (Lloyd et al. 2011). The 2010 survey also failed to uncover any new nesting grounds since the research of Göth and Vogel (1995, 1997).|
|♦ Estimated area of occupancy (AOO) - km2:||70||♦ Continuing decline in area of occupancy (AOO):||Unknown|
|♦ Extreme fluctuations in area of occupancy (AOO):||No||♦ Estimated extent of occurrence (EOO) - km2:||1800|
|♦ Continuing decline in extent of occurrence (EOO):||Unknown||♦ Extreme fluctuations in extent of occurrence (EOO):||No|
|♦ Number of Locations:||2||♦ Continuing decline in number of locations:||Unknown|
|♦ Extreme fluctuations in the number of locations:||No|
|♦ Upper elevation limit (metres):||50|
|Range Map:||Click here to open the map viewer and explore range.|
In the most comprehensive and robust population study on Niuafo’ou, Göth & Vogel (1995) used playback to estimate the global population to be 188-235 pairs. More recent surveys have been only brief and used different methods but only located 28-53+ birds (Butler 2014). Göth & Vogel (1995) recorded 187+ active burrows, but only 33 were found in 2012 (MLECCNR 2012) and 44 in 2014 (Butler 2014). On Fonualei Island, Watling (2004) recorded a minimum of 38 individuals, and estimated a population of 300-500. In 2012, Butler (2013) observed that birds were also abundant at another site in the north of the island, and estimated a population of 600-1000, assuming that all apparently suitable habitat had been occupied. Watling (2004) and (Butler 2013) recorded no birds on Late. Thus the population size may be best placed in the range 250-999 mature individuals (G. Dutson in litt. 2016).
Trend Justification: The overall population trend is tentatively considered to be a decline, as a result of reported declines on Niuafo'ou. However, the reintroduced population on uninhabited Fonualei may be considered to be increasing, and so the overall trend may warrant re-assessment in the future.
|Current Population Trend:||Decreasing|
|♦ Number of mature individuals:||250-999||♦ Continuing decline of mature individuals:||Yes|
|♦ Extreme fluctuations:||No||♦ Population severely fragmented:||No|
|♦ No. of subpopulations:||2||♦ Continuing decline in subpopulations:||Unknown|
|♦ Extreme fluctuations in subpopulations:||No||♦ All individuals in one subpopulation:||No|
|♦ No. of individuals in largest subpopulation:||1-89|