Publications

Hawaiʻi’s avifauna has undergone profound changes over the past 1,000 years, with many endemic bird species driven to extinction and non-native introductions reshaping forest ecosystems. On the island of Molokaʻi, habitat degradation and the introduction of mosquito-borne disease, mainly avian malaria (Plasmodium relictum), have caused extinctions and severe declines in native forest...

A critical component of monitoring wildlife populations is understanding changes in population size or abundance. However, for most populations a complete census is not possible; thus, trends or abundance need to be estimated through alternative means, such as indexes. An important aspect of using indexes, such as capture per unit effort (CPUE), is validating them as accurate or precise...

Passive acoustic monitoring has grown in utility for tracking wildlife populations, although challenges remain when using acoustic detections to monitor population size and density. Distance sampling is considered the ‘gold standard’ for estimating animal densities but has several important limitations, especially for rare, cryptic, and high-density species. Here, we test the performance...

The Ceratocystis fungal disease complex, rapid ʻōhiʻa death (ROD), has killed over one million ʻōhiʻa (Metrosideros polymorpha), the keystone tree species of Hawaiʻi. The causal fungi can be spread by invasive ambrosia beetles (Coleoptera: Curculionidae) through fungal inoculum found on their bodies and in the frass they produce. Thus, there is a critical need to manage beetle attack on...

The introduced mosquito-borne avian malaria, Plasmodium relictum, along with its mosquito vector, Culex quinquefasciatus, are key limiting factors for endemic Hawaiian forest birds and are, in part, responsible for past extinctions and continued population declines of extant species. In the last 10 years steep declines in forest bird populations have been documented on Kaua`i and Maui...

Tropical oceanic islands are critical biodiversity hotspots where population monitoring can help to determine the status and trends of rare and endangered species. Saipan is the second largest island in the Mariana Islands and contains many endemic and range-restricted bird species. Surveys of forest birds were conducted on Saipan using point-transect distance sampling, starting in 1982...

Wake Atoll, located in the central Pacific Ocean, is a tropical coral atoll comprised of three islands totaling 696 ha of emergent land. Wake Atoll supports at least 17 species of non-native ants, but one species, the yellow crazy ant (Anoplolepis gracilipes), is especially harmful to ecosystems, including seabirds, which are federally protected species and nest throughout Wake Atoll...

The National Park Service (NPS) Inventory and Monitoring Division (IMD) aims to provide data on park ecosystems' health to guide management decisions. Since 2007, NPS IMD has monitored water quality in marine areas, streams, anchialine pools, wetlands, and lakes in the Pacific Island Network (PACN) national parks. To maintain long-term monitoring program efficiency, protocols are...

Overexploitation, habitat conversion, and introduced species have caused unprecedented extinctions and heavily degraded native bird populations in island ecosystems. In the Hawaiian Islands, stemming these losses has proven difficult as the highly specialized avifauna are often impacted – among other things – by poorly understood trophic disruptions as well as persistent climatic shifts...

We investigated the reproductive ecology and effects of egg parasitism on the Samoan swallowtail butterfly (Papilio godeffroyi), which survives only on Tutuila Island, American Samoa, after having disappeared from the much larger islands of Upolu and Savai‘i in independent Samoa. During monthly surveys of its only known host plant, Micromelum minutum, across eight sites in 2013 and 2014...

The animal gut microbiome can have a strong influence on the health, fitness, and behavior of its hosts. The composition of the gut microbial community can be influenced by factors such as diet, environment, and evolutionary history (phylosymbiosis). However, the relative influence of these factors is unknown in most bird species. Furthermore, phylosymbiosis studies have largely focused...

This study updates the status assessment of four endemic endangered Hawaiian waterbird species—ae‘o (Hawaiian stilt, Himantopus mexicanus knudseni), ‘alae ke‘oke‘o (Hawaiian coot, Fulica alai), ‘alae ‘ula (Hawaiian gallinule, Gallinula galeata sandvicensis), and koloa maoli (Hawaiian duck, Anas wyvilliana)—from 1986 to 2016 by incorporating new data from 2017–2023. State-space models...