This year, Gov. David Ige named the Hawaiian hoary bat or ʻōpeʻapeʻa (Lasiurus cinereus semotus) the official state land mammal.

Native to Hawaii, the half-ounce, 10-15 inch bat (described as a”fat mouse with wings”) is currently listed as “endangered” and the U.S. Fish and Wildlife Service is working on a recovery plan. Once found on every island, hoary bat breeding (in case that’s your thing) currently only takes place on the Big Island and Kauai.

The bat is so popular, it has a Twitter account.

Hawaiian Hoary Bat

“Lasiurus cinereus semotus crop” by Forest & Kim Starr

Forest & Kim Starr

But a mystery has always bugged researchers: How did our little furry friends get to the Hawaiian islands? Now we know.

Using sophisticated DNA sequencing, a team of scientists has discovered that the Hawaiian hoary bat migrated to the islands from the Pacific Coast of North America in two separate waves — more than 9,000 years apart. The new study estimates that these migrations from mainland North America happened around 800 years ago and again 10,000 years ago.

That kind of migration represents the longest overwater flight followed with the founding of a new population for any bat, and there are over 1,300 species of bats worldwide. So take that, European Whiskered Bat!

“We used tiny bits of wing tissue and powerful DNA sequencing and analytical tools to estimate both the time and place of origin for this unique and cryptic mammal,” said Dr. Kevin Olival, senior research scientist at EcoHealth Alliance and study co-author.

This DNA sampling of Hawaiian hoary bats for conservation genetics studies began in 2004 and is ongoing. “Because the Hawaiian hoary bat is the only living native land mammal in Hawaii, we want to know everything possible about its genetic history, relationships to other bats, and if there are unique subpopulations on different Hawaiian islands,” said Dr. Amy Russell, associate professor of biology at Grand Valley State University and lead author of the study.

Bat DNA sampling locations in Hawaii

Hoary bat DNA sampling locations


And the researchers can even trace the bat’s possible itinerary: San Fran to Maui. Direct, of course.

Ecologists had previously modeled the path that the bats might have taken and found that the shortest possible flight distance from San Francisco to Maui, approximately 2,300 miles, is feasible with normal tailwind assistance from the prevalent Trade Winds.

This non-stop flight would only have required that the bat store the normal complement of fat that hoary bats accumulate for their annual migration through North America. Other surveys indicate that the bat can forage over many habitat types, including open ocean. Yes, these guys can also fish.

Due to isolation, all native plant and animal species originally colonized the Hawaiian Islands by long-distance dispersal via sea or air. For example, seeds or small animals may have hitched a ride on ocean debris, attached to bird feathers or feet, or drifted by air currents (spiders and very small insects).

No freeloader, ʻōpeʻapeʻa earned its place in the islands, one wing flap at a time.

Hawaiian Hoary bat, Lasiurus cinereus, Endangered, Hawaii Island, Laupahoehoe Forest Reserve

Jack Jeffrey

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