{"id":207812,"date":"2024-12-16T08:58:11","date_gmt":"2024-12-16T18:58:11","guid":{"rendered":"https:\/\/www.hawaii.edu\/news\/?p=207812"},"modified":"2024-12-16T09:11:28","modified_gmt":"2024-12-16T19:11:28","slug":"nuisance-alga-detected-majuro","status":"publish","type":"post","link":"https:\/\/www.hawaii.edu\/news\/2024\/12\/16\/nuisance-alga-detected-majuro\/","title":{"rendered":"Nuisance alga detected beyond Papah\u0101naumoku\u0101kea for the 1st time"},"content":{"rendered":"Reading time: <\/span> 3<\/span> minutes<\/span><\/span>
\"alga
The cryptic nature of the Majuro Chondria tumulosa<\/em>, pictured here, is how the alga was typically observed. (Photo credit: Patrick Nichols)<\/figcaption><\/figure>\n

A red alga first found by University of Â鶹´«Ã½<\/span> at M\u0101noa researchers smothering coral reefs in Papah\u0101naumoku\u0101kea Marine National Monument (PMNM<\/abbr>) has been detected for the first time by the team outside of the marine monument and more than 2,000 miles away.<\/p>\n

\"person
Researcher Jimmy Fumo takes a closer look at Majuro\u2019s reef to locate Chondria tumulosa<\/em>. (Photo credit: Patrick Nichols)<\/figcaption><\/figure>\n

The research team detected DNA<\/abbr> matching Chondria tumulosa<\/em> in Majuro Atoll in the Republic of the Marshall Islands in the east-central Pacific Ocean. Papah\u0101naumoku\u0101kea is a chain of islands and atolls that extends approximately 1,200 miles northwest of the main Hawaiian Islands in the northern Pacific.<\/p>\n

“Our discovery in Majuro suggests that C. tumulosa<\/em> may be more widespread than we previously thought. This could have significant implications for coral reef ecosystems across the Pacific, potentially requiring broader monitoring efforts and a more comprehensive understanding of the alga’s distribution and ecological impact,” said UH<\/abbr> M\u0101noa School of Life Sciences<\/a> graduate student Patrick Nichols.<\/p>\n

A threat to coral reefs<\/h2>\n

First detected in 2016 and named in 2020 by UH<\/abbr> researchers<\/a>, C. tumulosa<\/em> has earned a reputation for smothering coral reefs in PMNM<\/abbr>, where it forms dense mats that blanket corals and other native organisms. Its mat-forming behavior, ability to spread rapidly, and unknown origin have posed significant challenges for reef conservation.<\/p>\n

Until now, the alga had only been observed spreading throughout the three northwestern-most atolls of PMNM<\/abbr>: first at Manawai (Pearl and Hermes), then Kuaihelani (Midway Atoll) and H\u014dlanik\u016b (Kure Atoll). However, a new detection outside of Â鶹´«Ã½<\/span> caught the researchers by surprise.<\/p>\n

From eDNA<\/abbr> to field confirmation<\/h2>\n
\"coral
The near-pristine Majuro back reef where C. tumulosa<\/em> was observed in relatively low abundance. (Photo credit: Patrick Nichols)<\/figcaption><\/figure>\n

The discovery was made possible by the detection of the species\u2019 DNA<\/abbr> from water samples obtained earlier this year, emphasizing the pivotal role of environmental DNA<\/abbr> (eDNA<\/abbr>) as a front-line tool in the early detection of harmful nuisance species.<\/p>\n

The discovery in Majuro was a two-step process that combined molecular surveillance with targeted fieldwork to detect a species that is otherwise extremely difficult to visually identify. The process began with the eDNA<\/abbr> analysis, a bio-monitoring technique that screens water samples for the nuisance alga\u2019s genetic “fingerprint.”<\/p>\n

The genetic test for C. tumulosa<\/em> eDNA<\/abbr> was developed by UH<\/abbr> researchers<\/a> in partnership with the U.S. Fish and Wildlife Service and the National Oceanic and Atmospheric Administration, and can detect the presence of target species across vast areas without the need for extensive in-water surveys.<\/p>\n

Armed with this evidence, UH<\/abbr> graduate students Patrick Nichols (School of Life Sciences), Keolohilani Lopes Jr<\/abbr>. (Department of Natural Resources and Environmental Management<\/a>) and Jimmy Fumo (School of Life Sciences) traveled to Majuro in November 2024 to conduct an extensive survey, including the site of the initial positive eDNA<\/abbr> detection. Using microscopy and additional genetic sampling, they were able to visually confirm the presence of C. tumulosa<\/em>.<\/p>\n

Comparing alga behavior<\/h2>\n
\"large
Chondria tumulosa<\/em> forming thick mats on the reef at Manawai (Pearl & Hermes Atoll) in Papah\u0101naumoku\u0101kea Marine National Monument from July 2023. (Photo credit: NOAA PMNM<\/abbr>)<\/figcaption><\/figure>\n

At Manawai in PMNM<\/abbr>, C. tumulosa<\/em> has been observed forming thick mats that suffocate coral reef communities, displacing native flora and fauna. In Majuro, however, the species was observed in much lower abundance, forming small patches at some sites. This growth pattern resembles what was discovered in 2023 at H\u014dlanik\u016b (Kure Atoll) in PMNM<\/abbr><\/a> where C. tumulosa<\/em> grew cryptically and was difficult to identify.<\/p>\n

“Even though we have now observed C. tumulosa<\/em> outside of PMNM<\/abbr> we can\u2019t be sure of its native status,” Fumo said. “Its relatively low abundance in Majuro could mean it is either an emerging invader in the region or a long-established species being naturally controlled by herbivorous reef fishes or other ecological factors.”<\/p>\n

Broader surveys underway<\/h2>\n
\"high
One of the observation sites, Eneko, located on the northern end of Majuro atoll. (Photo credit: Patrick Nichols)<\/figcaption><\/figure>\n

With other potential sightings throughout the region, researchers plan to extend their surveys beyond the Marshall Islands to better understand the alga\u2019s distribution and ecological role. They hope to explore the historical connections between populations in Â鶹´«Ã½<\/span> and elsewhere to determine if the species has recently spread across the north Pacific or has been established in the region for a longer period of time.<\/p>\n

The team\u2019s work in Majuro builds on years of collaboration between UH<\/abbr> M\u0101noa researchers and local stakeholders throughout the Hawaiian archipelago.<\/p>\n

“While this discovery raises concerns about the spread of C. tumulosa<\/em>, it also showcases the incredible potential of new technologies and collaboration,” Nichols said. “By working together on new tools, we can better understand and mitigate the risks posed by nuisance species.”<\/p>\n","protected":false},"excerpt":{"rendered":"

Researchers plan to extend their surveys beyond the Marshall Islands to better understand the alga\u2019s distribution and ecological role. <\/p>\n","protected":false},"author":16,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[30],"tags":[308,665,109,1085,1363,1314,544,568,1473,73,9],"class_list":["post-207812","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-research","tag-college-of-natural-sciences","tag-conservation","tag-coral-reefs","tag-life-science","tag-manoa-research","tag-manoa-sustainability","tag-natural-resources-and-environmental-management","tag-natural-science","tag-school-of-life-sciences","tag-sustainability","tag-uh-manoa","entry","has-media"],"aioseo_notices":[],"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/posts\/207812","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/users\/16"}],"replies":[{"embeddable":true,"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/comments?post=207812"}],"version-history":[{"count":6,"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/posts\/207812\/revisions"}],"predecessor-version":[{"id":207827,"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/posts\/207812\/revisions\/207827"}],"wp:attachment":[{"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/media?parent=207812"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/categories?post=207812"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/tags?post=207812"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}