New research is being done on a familiar amphibian found on all the main Hawaiian Islands.
The bullfrog first arrived in Hawaiʻi around 120 years ago. Now the International Union for Conservation of Nature considers it one of the worst invasive species in the world.
They live in low-elevation wetlands, also home to the nests of endangered birds.
Hawaiʻi Pacific University researcher Heidi Beswick is studying the frog’s invasive ecology.
"They are carnivores, voracious predators. And they can eat anything that fits in their mouth. So that makes them a threat to a lot of native species in the areas where they invade," she said.
Beswick says they've been observed eating bats, birds, small mammals, other frogs, fish, snakes and scorpions.
"They can lay 20,000 eggs at a time, which is a lot. So they're very reproductively successful," Beswick said. "In Hawaiʻi, it's possible that they're laying way more clutches than they would on the mainland because they don't have a hibernation season here in Hawaiʻi, so they could lay possibly, like 60,000 eggs in a season."
Beswick has collected data on roughly 200 frogs in more than two years, building a genetic tree to compare the structural differences between bullfrogs in Hawaiʻi and the mainland.
To mark Hawaiʻi Invasive Species Awareness Month, The Conversation will have updates throughout February on the battle against invasive species across this state. This interview aired on The Conversation on Feb. 14, 2022. The Conversation airs weekdays at 11 a.m. on HPR-1.
