Tracking the Spread of Rapid ʻŌhiʻa Death on Kauaʻi (w/ video)

Rapid ʻŌhiʻa Death was first detected on Kauaʻi in May 2018. New surveys recently detected the fungal disease in two new areas on Kauaʻi, the upper Hanalei valley and along the north side of Powerline Trail. Photo courtesy of DLNR

Researchers at the University of Hawaiʻi Pacific Cooperative Studies Unit have collaborated with multiple agencies to develop a management tracking system to keep crucial data organized as the Rapid ʻŌhiʻa Death fungus continues to spread to parts of Kauaʻi, facilitate planning of management and research activities, and provide progress updates, according to a UH news report. The system allows field staff to compile data from multiple sources into one place.

“Supporting the work on Kauaʻi is one of my highest priorities,” said Brian Tucker, PCSU ROD data manager, who supports all aspects of statewide management planning, field implementation and reporting. “Electronic data collection in the field and geospatial data management enable field staff on Kauaʻi to track outbreaks and new discoveries of ROD.”

Clean gear and tools, including shoes and clothes, before and after entering the forest and areas where ʻōhiʻa may be present. Video grab courtesy of DLNR

The compiled data begins with suspect ROD trees, or trees that have recently died and exhibit ROD symptoms. Data is mostly compiled through aerial surveys via helicopter or drone, but also includes ground reporting by landowners.

Suspect ROD trees are then entered into the database, where they are prioritized based upon multiple criteria of location and accessibility. These suspects then may be visited for sampling and other research activities. Observations are made and entered into the database during visits and re-visits. The tracking system allows multiple agencies to know what has been completed, and when. Over time, the data will show how the disease has grown and spread.

To date, there have been a total of 181 confirmed ROD cases on Kauaʻi, which includes 101 Ceratocystis lukuohia, the more aggressive and devastating species. There have been 78 Ceratocystis huliohia fungus infected species. Two of the confirmed cases were co-infected with both species.

Mitigation Efforts

Monitoring of forests began prior to ROD being discovered on Kauaʻi when the first samples of dead ʻōhiʻa were collected in February 2016. While ROD was not detected, the Hawaiʻi Department of Land and Natural Resources Division of Forestry and Wildlife began doing aerial surveys to locate ROD suspects in June 2016. Mitigation efforts began immediately after ROD was first discovered on Kauaʻi in May 2018.