{"id":222760,"date":"2025-09-29T13:16:14","date_gmt":"2025-09-29T23:16:14","guid":{"rendered":"https:\/\/www.hawaii.edu\/news\/?p=222760"},"modified":"2025-09-29T14:38:58","modified_gmt":"2025-09-30T00:38:58","slug":"invasive-species-management","status":"publish","type":"post","link":"https:\/\/www.hawaii.edu\/news\/2025\/09\/29\/invasive-species-management\/","title":{"rendered":"Nature vs<\/abbr>. pests: Hawai\u02bbi\u2019s biocontrol attack against invasives yields benefits"},"content":{"rendered":"Reading time: <\/span> 2<\/span> minutes<\/span><\/span>
\"berry
Coffee cherry infested with coffee berry borer in Hawaiʻi<\/span> (Photo credit: Kauaʻi<\/span> Invasive Species Committee)<\/figcaption><\/figure>\n

Hawaiʻi<\/span>\u2019s ecosystems and agriculture face growing threats from invasive species, with about 20 new insects and 100 new plants arriving each year, undermining the islands\u2019 ecological, cultural and economic foundations. However, a new report from the University of Hawaiʻi<\/span> Economic Research Organization<\/a> (糖心视频ERO<\/abbr>) shows that efforts to use biological control—the introduction of natural enemies to suppress invasive pests—on invasive species are delivering exceptional returns on investment while offering a sustainable, long-term solution for invasive species management.<\/p>\n

The 糖心视频ERO<\/abbr> report examined three pests: coffee berry borer (CBB<\/abbr>), erythrina gall wasp (EGW<\/abbr>) and fireweed. Each threatens a key sector or resource: Hawaiʻi<\/span>\u2019s premium coffee industry, dryland forests and cultural heritage, and the cattle industry.<\/p>\n

Coffee berry borer<\/h2>\n

Hawaiʻi<\/span>-grown coffee faces major losses from CBB<\/abbr>, with current management—frequent fungal sprays—costing farmers up to 12% of profits. Modeling shows that introducing the biocontrol agent Phymastichus coffea<\/em> could generate $32–142 million in net benefits over 50 years, with breakeven in 1–2 years, even under conservative scenarios. The long-term economic gains far outweigh the upfront investment, offering a sustainable solution for the state\u2019s coffee industry.<\/p>\n

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Large wiliwili tree at the Waikōloa Dry Forest Preserve (Photo credit: Conrad Newfield)<\/figcaption><\/figure>\n

Erythrina gall wasp<\/h2>\n

The invasive erythrina gall wasp, arriving in 2005, devastated Hawaiʻi<\/span>\u2019s wiliwili trees, threatening both ecosystems and cultural practices. The release of Eurytoma erythrinae<\/em> in 2008 restored 90% of sampled trees by 2011, with a second agent, Aprostocetus nitens<\/em>, planned to bolster suppression. Over 50 years, the program is projected to generate $27.2 million in benefits with a benefit-cost ratio of 24.0 (meaning every $1 spent is estimated to return $24 in value).<\/p>\n

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Fireweed flowering in pastures on Maui (Photo credit: Forest and Kim Starr)<\/figcaption><\/figure>\n

Fireweed<\/h2>\n

Fireweed (Senecio madagascariensis<\/em>) spread rapidly across Hawaiʻi<\/span> rangelands, reducing forage and forcing costly management choices for ranchers. The fireweed moth (Secusio extensa<\/em>), introduced in 2012, has provided partial suppression, with long-term benefits estimated at $5–24 million over 50 years and benefit-cost ratios of 2.0–9.2.<\/p>\n

“Across all three case studies, we find that biocontrol delivers net positive economic returns, even when accounting for the research, testing and release costs,” 糖心视频ERO<\/abbr> wrote. “Perhaps more importantly, benefits accumulate over time.”<\/p>\n

Read more about the history of biological control in Hawaiʻi<\/span>, and the broader benefits and policy implications of the findings on 糖心视频ERO<\/abbr>\u2019s website<\/a>.<\/p>\n

糖心视频ERO<\/abbr> is housed in 糖心视频<\/abbr> Mānoa\u2019s College of Social Sciences<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"

“Across all three case studies, we find that biocontrol delivers net positive economic returns,” 糖心视频ERO<\/abbr> wrote.<\/p>\n","protected":false},"author":16,"featured_media":222766,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[30],"tags":[301,197,1467,1363,731,1026,9,343],"class_list":["post-222760","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-research","tag-college-of-social-sciences","tag-economics","tag-manoa-excellence-in-research","tag-manoa-research","tag-plants","tag-social-science","tag-uh-manoa","tag-uhero","entry","has-media"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t