Avian Malaria Now Detected Across Nearly All Mosquito Habitats in Hawaiʻi

Recent scientific research has documented widespread avian malaria throughout Hawaiʻi, affecting native bird populations and prompting targeted conservation responses. The findings highlight the ongoing threat posed by mosquito-borne diseases to the region’s unique forest birds.

A study published in February 2026 in Nature Communications reported that avian malaria was present at nearly every location where mosquitoes were sampled across the Hawaiian Islands. Researchers examined blood samples from over 4,000 birds on Maui, Kauaʻi, Oʻahu, and Hawaiʻi Island, confirming that both native and introduced species are capable of infecting southern house mosquitoes with the malaria parasite.

Transmission of the disease was observed even in birds carrying very low levels of the parasite, increasing the risk of spread among bird communities. The study’s results indicate that avian malaria is now established wherever mosquitoes exist in the islands, reducing the number of safe habitats for susceptible species.

What the numbers show

• Avian malaria detected at 63 out of 64 sampled sites
• Over 4,000 birds were tested across four major islands
• The ʻiʻiwi honeycreeper has a 90% mortality rate from infection
• Some bird species, such as the kiwikiu and ʻakikiki, have populations below 200

Native forest birds in Hawaiʻi, including honeycreepers, are highly vulnerable to avian malaria transmitted by invasive southern house mosquitoes. The ʻakikiki, a native honeycreeper, is now considered extinct in the wild, while other species like the kiwikiu have critically low population numbers.

Warming temperatures are contributing to the decline of mosquito-free high-elevation areas, according to research findings. As a result, mosquitoes and avian malaria are reaching habitats that were previously isolated from these threats, further endangering remaining bird populations.

Climate change has been identified by the U.S. National Park Service as a factor enabling mosquitoes to expand into higher elevation forests. This expansion threatens the last refuges for many native birds, which have limited resistance to the disease.

Conservation initiatives under the 'Birds, Not Mosquitoes' partnership are focusing on mosquito control to help protect the remaining native forest birds. One approach being used is the Incompatible Insect Technique, which involves releasing Wolbachia-infected male mosquitoes to suppress wild mosquito populations in targeted areas.

These combined research efforts and conservation strategies are being implemented to address the ongoing spread of avian malaria and to support the survival of Hawaiʻi’s endemic bird species.

* This article is based on publicly available information at the time of writing.