Justification of Red List Category
This species formerly occurred on the Hawaiian island of Kaua'i, USA, but the multitude of threats in the region have driven it Extinct. The last definite record dates from 1985 and targeted searches in 1995 and 1997 yielded no confirmed reports.
Myadestes myadestinus was endemic to Kaua'i in the Hawaiian Islands (USA). It was the most common of the forest birds in 1891 but, by 1928, had disappeared from the lower altitudes and became restricted to dense montane forest in the Alaka'i Wilderness Preserve (Scott et al. 1986). During 1968-1973, its population was estimated at 337 individuals (USFWS 1983) while, in 1981, an estimated 24 (±20) individuals were present (Scott et al. 1986). The last reliable sighting was in 1985, with unconfirmed reports until 1991 (Gorresen et al. 2009). The lack of confirmed detections despite numerous intensive surveys in areas formerly occupied, particularly in 1995 and 1997 (Reynolds and Snetsinger 2001, Foster et al. 2004), make it now appropriate to classify this species as Extinct (S. Fretz, R. Camp, E. VanderWerf and M. Gorresen in litt. 2003). However, it is worth noting that M. palmeri went many years without being seen, but then began to reappear in small numbers (USFWS 2003).
Originally inhabited forest at all elevations, but since 1920s restricted to dense montane forest.
Disease carried by introduced mosquitoes and the destruction and degradation of forests are likely to have been the chief causes of extinction (USFWS 1983). The advance of feral pigs into pristine upland forests degraded habitat and facilitated the spread of mosquitoes (Pratt 1994). Competition with introduced birds may have exacerbated the problems faced by this species (Wakelee and Fancy 1999), and introduced predators are likely to have also played a part (Woodworth et al. 2009). Deprived of lowland forest the species was also exposed to the effects of hurricane damage in upland forest, which severely disrupted portions of native forest and allowed the germination and expansion of noxious weeds (Pratt 1994, Conant et al. 1998). Also potentially detrimental to the remaining suitable habitat are introductions of new alien invertebrates, such as the two-spotted leafhopper (Sophonia rufofascia), which may threaten many food plants of M. myadestinus (USFWS 2003).
20 cm. Small, dull-coloured thrush. Reddish-brown above, pale grey below, breast and flanks with slightly darker mottling. Dark legs. Short, broad bill. Juvenile dark chocolate-brown above heavily spotted with buff, grey below heavily scalloped with dark brown. Similar spp. Puaiohi M. palmeri smaller with pink legs and longer, more slender bill. Introduced Melodious Laughingthrush Garrulax canorus brighter cinnamon-brown with yellow bill. Voice Song a long melodic cascade of notes including buzzy trills, gurgling whistles, and shorter notes. Calls a variety of short notes including cat-like or frog-like braack and higher pitched police whistle. Hints Sings from exposed snags in early morning.
Text account compilers
Benstead, P., Butchart, S., Harding, M., Khwaja, N., Mahood, S., Martin, R
VanderWerf, E., Fretz, S., Gorresen, M., Woodworth, B., Camp, R.
BirdLife International (2020) Species factsheet: Myadestes myadestinus. Downloaded from http://www.birdlife.org on 30/09/2020. Recommended citation for factsheets for more than one species: BirdLife International (2020) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 30/09/2020.