Distribution

Thrushes and chats can be found on most land masses except for Antarctica, although only two artificially introduced species occupy New Zealand. A number are extremely restricted in their range. Three species of rock thrush (Monticola) are found only in Madagascar; whistling-thrushes (Myophonus) include one species restricted to Sri Lanka, another to Malaysia, and another to Taiwan. The rarely seen geomalia (Geomalia heinrichi) is a rufous and brown thrush found only in Sulawesi rainforests, but is not the only thrush restricted to Sulawesi. The Amami thrush (Zoothera major) is found on just one small island in the Ryukyu Islands south of Japan, while other Zoothera thrushes are also confined to one or two islands and several Myadestes thrushes are found only within the Hawaiian group. Even within Turdus, there are species with remarkably restricted ranges, including various African islands, while Tristan da Cunha, a remote South Atlantic island group, the Tres Marias Islands off Mexico, and several West Indies islands also have their own unique thrushes. The Seychelles magpie-robin (Copsychus sechellarum) was, until the 1990s, restricted to just one Seychelles island with only 20 individuals, before translocation to other islands in the group helped a recovery to more than 100 individuals by 2001.

These, however, are the exceptions to the general rule, with most species having quite extensive geographical ranges. Some are long-distance migrants such as the northern wheatear. Birds of this species breeding in Greenland set off on a massive trans-oceanic flight direct to Africa each fall, and return in spring via western Europe. The whinchat (Saxicola rubetra) spends each winter in Africa but moves north in spring to breed in Europe, often alongside the similar stonechat (S. torquata), which is an all-year resident in Europe and also in much of Africa. American robins breed throughout North America as far as the northern coasts of Alaska and mainland Canada and south to Mexico, but vast numbers from the northern two-thirds of this huge range move south in winter to join their more southerly relatives. Of the spotted thrushes in North America, the hermit thrush (Catharus guttatus) is the most widespread and the only one that commonly winters in much of the United States. Several thrushes breed in an extensive range across Europe and northern Asia, including the redwing (Turdus iliacus), hundreds of thousands of which pour out of cold Asia and northern Europe in autumn to find milder conditions in western and southern Europe each winter. The dusky thrush (T. nau-manni), however, moves south instead of west, to winter in Japan and south-east Asia, while the dark-throated thrush (T. ruficollis) moves south from central Asia to spend the winter months in a belt just north of the Indian subcontinent. The blackbird has one of the most extensive ranges of all, from northwest Europe eastwards and south across Eurasia to the Oriental region, and into Australia and New Zealand. The stonechat has one of the widest ranges of Old World chats, breeding from Britain and Ireland south and east through Eu-

A gray-cheeked thrush (Catharus minimus) sings while perched on a branch. (Photo by C. Witt/VIREO. Reproduced by permission.)

rope, through East Africa south as far as the Cape, in Madagascar and Arabia and, in a separate area of distribution, through a vast area of central and eastern Asia and Japan.

Was this article helpful?

0 0

Post a comment