The islands’ pueo are running into serious trouble on the road. A new statewide analysis led by University of Hawaiʻi at Mānoa researchers finds that most pueo, the Hawaiian short-eared owl, recovered dead across the state were killed by human-related trauma, especially vehicle strikes. Drawing on 242 confirmed mortalities from 1993 through 2024, the team points to roads and other infrastructure as major hazards for this culturally important raptor. It is the first island-wide synthesis of pueo mortality and is meant to guide future conservation moves.
Study details and key findings
According to the Journal of Field Ornithology, researchers compiled 242 unique mortality records from 10 state, federal and private organizations covering 1993–2024, and found that trauma accounted for 62% of documented pueo deaths. Of the 150 trauma cases, about two-thirds involved direct vehicle collisions or occurred very close to roadways, while roughly 13% of trauma-related deaths were tied to wind turbines. The paper also reports that recorded mortalities increased over time, although the authors caution that more reports could reflect both improved monitoring and real changes in pueo populations.
Researchers call for a statewide assessment
Researchers say the numbers point to straightforward ways to curb preventable deaths. In a statement to University of Hawaiʻi News, senior author and NREM professor Melissa Price said, “Our findings highlight that many Pueo deaths may be preventable,” and urged efforts to cut down on vehicle collisions and boost awareness about rodenticide use. U.S. Fish and Wildlife Service biologist Olivia Wang told University of Hawaiʻi News that the study “adds to a growing body of research” showing native birds in Hawaiʻi are killed by collisions with vehicles and infrastructure.
Underlying health problems and reporting gaps
The review also found that many birds were dealing with parasites, emaciation or suspected rodenticide exposure, which may increase their vulnerability to trauma, according to the Journal of Field Ornithology. The islands of Hawaiʻi and Kauaʻi accounted for the largest share of recorded mortalities. At the same time, the authors warn that uneven reporting across islands and the lack of systematic necropsies make it difficult to pinpoint exactly what is driving the deaths. They recommend improving reporting to federal wildlife databases and pursuing targeted fieldwork and toxicology studies to clarify causes and trends.
What this means on the ground
“Without systematic necropsies and toxicology testing it can be difficult to untangle contributing factors in wildlife mortality,” U.S. Geological Survey collaborator Thierry Work told University of Hawaiʻi News. Study authors and partners say actions ranging from public outreach about rodenticide risks to roadway interventions, including signage, speed management and carefully evaluated barriers or diversion measures, should be piloted and monitored to see what actually works. They emphasize that a statewide population assessment is a critical next step so managers can judge whether current mortality levels are a measurable threat to pueo populations.
