Summary

Description

Mosquitoborne avian disease, avian malaria and avian pox, is a major limiting factor for Hawaiian forest birds. While native bird communities at Hakalau Forest NWR remain intact and species populations are stable or increasing, these birds are still vulnerable to the impact of avian disease. Continued increases in mean air temperature at higher elevations and large scale environmental change caused by feral pigs within the unmanaged units of the refuge may have resulted in increased disease transmission at Hakalau NWR. To determine if disease transmission rates have changed in 15 years we performed a oneyear survey that builds upon earlier research, updates the prevalence and distribution of avian disease and vector mosquitoes and helps assess future avian disease risk at Hakalau Forest NWR. The main objective of the study is to compare current avian malaria prevalence and vector mosquito occurrence with data collected in 19981999 across a broad landscape of Hakalau Forest NWR. Specifically, we collected blood samples from birds at the Pua Akala, Nauhi and Maulua Tracts at 1,800 m asl and Pua Akala and Maulua Tracts at 1,300 m asl and performed standard diagnostics to determine infection prevalence with avian malaria, avian pox and knemidokoptic mange. Also, we surveyed pig sign and larval mosquito habitat along belt transects and larval mosquito habitat along the Awehi and Waikaumalo stream drainages.