The 'Bonin Thrush', 'Bonin Islands Thrush' or 'Kittlitz's Thrush' (''Zoothera terrestris'') is sometimes separated as the only species of the genus ''Cichlopasser''. It is an
extinct species of
Asian thrush. The only place where this bird ever was found is
Chichi-jima in the
Ogasawara Islands; it might theoretically have also occurred on
Anijima and
OtÅtojima, but this is not borne out by observations or specimens. The species was only once observed by a naturalist, its discoverer
Kittlitz. He encountered the thrush in the coastal woods where it usually kept to the ground; it may have been ground-nesting. The only specimens ever taken are in the
Naturalis in
Leiden (1), the
Naturhistorisches Museum in
Vienna (1), the
Senckenbergmuseum in
Frankfurt (1) and in the
Zoological Museum,
St. Petersburg (2).
Extinction
Interestingly, the Bonin Thrush is not among the birds observed or collected by the
Beechey Pacific expedition which called at Chichi-jima in
1827. It was only found the following year, when Kittlitz took the 5 specimens; he considered them common enough around the landing site. It is unknown why Beechey's expedition, which landed at the same location, did not find them.
Following the suggestion of two shipwrecked sailors (who were picked up by Beechey in 1827) that the island would make a good stopover station for
whalers, settlement was begun in
1830. When the
Perry's first mission to
Japan called at Chichi-jima in
1853, they did not find the bird again, just as naturalist
William Stimpson of the
Rodgers-
Ringgold North Pacific Exploring and Surveying Expedition in the following year. Instead, they encountered rats and feral goats, sheep, dogs and cats (feral pigs were already found by Kittlitz and may have been left by Beechey to provision possible future castaways). Just like the
Bonin Grosbeak, the Bonin Thrush probably succumbed soon after 1830 to predation by the introduced mammals and habitat destruction.
References
★ Database entry includes justification for why this species is extinct
★ Kittlitz, Heinrich von (1830): [Description of ''Zoothera terrestris'']. ''Mem. presentes a l'Acad. Imp. des Sci. de St. Petersbourg par divers savants, etc.'' '1'(3): 244, plate 17.