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Invasive species are a leading driver of global change, with consequences for biodiversity and society. Because of extraordinary rates of endemism, introduction, and extinction, Hawaii offers a rich platform for exploring the cross-disciplinary challenges of managing invasive species in a dynamic world. We highlight key successes and shortcomings to share lessons learned and inspire innovation and action in and beyond the archipelago. We then discuss thematic challenges and opportunities of broad relevance to invaded ecosystems and human communities. Important research needs and possible actions include eradicating mammals from mainland island sanctuaries, assessing hidden threats from poorly known introduced species, harnessing genomic tools to eradicate disease vectors, structured decision-making to achieve common objectives among diverse stakeholders, and enhancing capacity through nontraditional funding streams and progressive legislation. By shining a spotlight on invasive species at the front lines in Hawaii, we hope to catalyze strategic research and practice to help inform scientists and policymakers. [ABSTRACT FROM AUTHOR]

Anthropogenic disturbance is restructuring ecosystems and changing interactions within ecological communities. On the Hawaiian Islands, habitat degradation is linked to the establishment of invasive species; and together these stressors may lead to declining native populations and changes in food webs. In this study we employed stable isotopes to examine the structure of multiple Hawaiian stream food webs with varying levels of these stressors to illustrate interactions between native and non-native organisms that may represent drivers of community change. Limahuli stream contains all five species of native Hawaiian gobies, has a small number of introduced species, and minimal human disturbance. 'Opaeka'a, Hule'ia and Kapa'a streams are more heavily invaded than Limahuli and have greater human influence. We found increased species richness, increased trophic diversity, and increased total niche area in the more heavily invaded stream food webs relative to Limahuli. We also found non-native predatory species inhabiting top trophic positions in the three more heavily invaded streams and isotope mixing model estimates suggest that several species of non-natives have overlapping prey sources with native gobies in these sites. Lastly, we found that native stream organisms were nearly absent in 'Opaeka'a stream which also had the highest percent urban development of the streams sampled. Our results suggest significant trophic changes have occurred as the result of introduced species and possibly related to increased human disturbance. [ABSTRACT FROM AUTHOR]