Forest afflicted with Rapid Ohia Death

Along with decimating native ʻōhiʻa forests, Rapid ʻŌhiʻa Death poses a serious threat to the plants and animals that depend on ʻōhiʻa trees. Photo: Department of Land and Natural Resources.

Kristina Paxton

Patrick Hart

The University of Hawaiʻi at Hilo will examine the effect of Rapid ʻŌhiʻa Death (ROD) on animal communities in Hawaiʻi with a $197,056 grant from the National Science Foundation Grants for Rapid Response Research.

“This project will use advances in recording technology to continuously record over an extended period of time the entire sound-producing animal community within ʻōhiʻa forests across Hawaiʻi Island,” said Kristina Paxton, adjunct assistant professor of tropical conservation biology and environmental science. “By using soundscape analysis tools developed within the growing field of soundscape ecology, we will be able to rapidly assess changes in the biodiversity of audible birds, insects, and amphibian species associated with the mortality of ʻōhiʻa across the landscape.”

Paxton and Patrick Hart, professor of biology, both members of the Listening Observatory for Hawaiian Ecosystems Bioacoustics Lab, will evaluate whether the diversity and composition of understory plant species moderates how reliant animal communities respond to the loss of a dominant forest tree species.

“The use of soundscape indices to model biodiversity following the loss of a foundation species represents a novel and relatively rapid method for assessing ecological change, and would be applicable in a range of ecosystems outside of Hawaiʻi,” Paxton said.

Serious threat to Hawaiʻi’s forest plants and animals

ROD is a fungal pathogen causing rapid and widespread mortality of ʻōhiʻa (Metrosideros polymorpha), a foundation tree species in Hawaiian forests. ROD poses a serious threat to Hawaiʻi’s remaining native forests and the plants and animals that depend on ʻōhiʻa. ROD research has been concentrated on understanding the pathology of the disease, how ROD is spread and the impacts of ROD on ʻōhiʻa trees.

“Despite these studies, however, there has not been an examination of how ROD is affecting animal communities reliant on ʻōhiʻa forests, which is an important nesting substrate and food resource for both insectivorous and nectarivorous Hawaiian forest birds, 57 percent of which are threatened or endangered,” Paxton explained. “Given the foundational role of ʻōhiʻa in Hawaiian forests as the dominant tree in the canopy, widespread or total loss of ʻōhiʻa would likely be catastrophic for endemic Hawaiian forest birds.”

The grant award ends June 30, 2019.

For more, see the UH Hilo news release and UH Hilo Stories.