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 Ot?tojima, 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.