Some of the passerine birds have been the most widely distributed, especially the house-sparrow (Passer domesticus), which is now an integral, and very troublesome, part of the fauna in the Australasian States and in North America.
The house-sparrow is also feral in Argentina, some of the West Indian islands, Hawaii and the Andamans.
The allied tree-sparrow (P. montanus) has been locally naturalized in the United States; it is a more desirable bird, being less prolific and pugnacious, but it is expelled from towns by the house-sparrow.
Returning to the true finches, the only one which can compete with the house-sparrow in the extent of its distribution by man is the goldfinch (Carduelis carduelis), now established all over New Zealand, as well as in Australia, the United States and Jamaica.
Seedlings have been raised from the excreta of various birds including the house sparrow.