More than a thousand species of birds occur in Mexico and in the adjacent countries of Belize, Guatemala, and El Salvador. Of these birds, a unique mixture of temperate-zone and tropical species, less than half are found in the United…
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More than a thousand species of birds occur in Mexico and in the adjacent countries of Belize, Guatemala, and El Salvador. Of these birds, a unique mixture of temperate-zone and tropical species, less than half are found in the United…