Predicting Invasive Species Impacts

Introduced rats are notorious predators of birds and their nests worldwide, but especially on remote islands. Rats ( Rattus exulans) first arrived in Hawai‘i with Polynesian colonists about 1,000 years ago, resulting in deleterious consequences for native birds and ecosystems. Since Western contact in 1778, two additional rat species have become established in Hawai‘i, including the highly...

Rapid ‘Ōhi‘a Death (ROD) is an emerging and rapidly spreading disease of ‘ōhi‘a ( Metrosideros polymorpha), a keystone native forest tree in the Hawaiian Islands. The disease is highly pathogenic in native ‘ōhi‘a and can lead to significant mortality once symptoms become evident. This emerging pathogen is a significant threat to native forests throughout the state because of its potential impacts...

Small mammals (including three species of rats and one species of mongoose) and social Hymenoptera (order of insects including ants and yellowjacket wasps) form two groups of alien predators in Hawaiian ecosystems. The combined impact of these predators has resulted in substantial loss or reduction of native biota in the Pacific. Furthermore, given the past successes of managing or excluding feral...

Feral pigs ( Sus scrofa) have been identified as a significant problem in 120 U.S. National Wildlife Refuges. Pigs cause substantial degradation to natural ecosystems through rooting, digging, and browsing, but they are particularly destructive in Hawai‘I, which has no native terrestrial large mammals.

Avian botulism causes waterbird mortality in Hawai‘i's wetlands and elsewhere. We evaluated bird mortality using trained scent-detection canines (sniffer dogs) as a new tool to survey for the presence of avian botulism. Biologists compare variables influencing detection probability and detection rates with traditional search methods. The pilot study tested the feasibility of this approach as a new...

Islands and atolls throughout the Pacific have been impacted by invasive ant species. Threatening native ants and other arthropods with their aggressive behavior and ability to colonize large geographic areas, invasive ants pose one of the most serious threats to island ecosystems. This project focuses on three areas of the Pacific: American Samoa, Rose Atoll, and Johnston Atoll.

Six species of biting mosquitoes have been introduced to the Hawaiian Islands since Western contact, two of which are vectors of dengue, chikungunya, and Zika viruses. Environmental conditions favorable for the transmission of dengue and Zika occur year-long across Hawai‘i’s coastline. To better understand the ecology of vector mosquitoes and support public health efforts, mosquito monitoring at...