For about a month, starting in late April and ending in late May, dozens of species of warblers pass through Louisville on their northern migration. These little birds, with wingspans of just eight or nine inches and weighing less than half an ounce, begin their journey in Central and South America. Some of them migrate more than 5,000 miles one-way to their breeding grounds in the northern United States and Canada.
Read MoreBlackburnian Warbler (Setophaga fusca) | Cherokee Park | Louisville, KY