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a typical example of this is provided by the wheatear, a small bird that travels to the maremma in april and in september. every year, the wheatear population moves from africa as far as siberia; a small group even reaches alaska via the bering strait, travelling 16,000 km twice every twelve months, an incredible feat for a bird weighing only a few grammes!
tipico in questo senso è l'esempio del culbianco, un piccolo uccello che passa in maremma in aprile e in settembre.