Around 10,000 years ago, the Hawaiian Hoary Bat (Lasiurus semotus) made its way across a vast expanse of the Pacific Ocean to take up residence in Hawaii.

Hawaiian Hoary Bat. Photo by Jack Jeffrey.

About 1.3 million years ago, Hoary bats from North America made their way across a vast expanse of the Pacific Ocean to take up residence in Hawaii, eventually differentiating into the Hawaiian Hoary Bat (Lasiurus semotus).

Researchers found the bats must have covered at least 2,200 miles, which they noted is “highly feasible with normal tailwind assistance from the prevalent Trade Winds.” Another theory involves these bats catching a ride on objects drifting across the ocean.

The Hawaiian Hoary Bat is the state’s only native terrestrial mammal, and it became the state’s official land mammal in 2015. It is closely related to the North American Hoary Bat. It is also federally protected as an Endangered species under the Endangered Species Act in the U.S.

In Hawaii, these bats are called ʻŌpe‘ape‘a, which translates to “half-leaf” in reference to how the bat’s wings—which can have up to a one-foot wingspan—look like half a taro leaf.

Roosting in trees, these insectivores seek out moths, flies, beetles, and other insects to eat. In a single night, they have been documented to travel 12 miles.

But these incredible bats are endangered, facing threats like habitat destruction as well as collisions with objects like barbed wire fences and wind turbines.

Located in the middle of a vast ocean, Hawaii aims to use only renewable energy by 2045. Wind energy is an important renewable energy source, but can be deadly for bats. However, researchers are studying ways to reduce bat fatalities at wind turbines. 

One possible solution is to alter or curb wind turbine operations during times of low wind, which has been shown to reduce bat fatalities. Bat Conservation International is working to help protect bats while also testing scalable and practical  solutions that enable renewable energy production.