By observing roost options of the initial residents, bat choices can be established and fulfilled by differing the shade or sunlight exposure for subsequent houses. The ancestors of the jeopardized Hawaiian Hoary Bat traveled over 3,600 kilometers from the Pacific Coastline nearly 10,000 years ago to become Hawaii's state land mammal. Photo by Frank Bonaccorso, USGS.9. The longest-living bat is 41 years old. It's claimed that the smaller the animal, the shorter its life-span, however bats break that guideline of long life.