Basin-wide patterns of abundance of a widespread invasive herbivore in the Mediterranean Sea

Basin-wide patterns of abundance of a widespread invasive herbivore in the Mediterranean Sea | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Basin-wide patterns of abundance of a widespread invasive herbivore in the Mediterranean Sea Andrea Anton, Xavier Bachot, Maria Pizarro-Borrull, Sara Muñiz-Quintana, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8523331/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 5 You are reading this latest preprint version Abstract Biological invasions continue to accumulate globally, yet basic ecological information is lacking for many widespread marine non-native species. The tropical–subtropical herbivorous crab Percnon gibbesi has expanded rapidly throughout the Mediterranean basin but quantitative assessments of its abundance remain geographically limited. This knowledge gap is particularly relevant given the demonstrated capacity of the species to heavily graze macrophytes under laboratory conditions and the rapid proliferation of artificial coastal structures that may further enhance its abundance. To address these gaps, we quantified P. gibbesi densities at 79 sites across the Mediterranean Basin, encompassing both natural rocky habitats and artificial hard substrates. On average, P. gibbesi was nearly twice as abundant on artificial structures as on natural substrates, and its abundance increased towards the eastern Mediterranean. Although mean densities were high (36.2 individuals per 100 m²), abundance varied markedly among sites and regions, suggesting that - assuming a positive relationship between abundance and impact - the ecological impacts of this invader are likely to be highly heterogeneous across Mediterranean landscapes. Together, these findings provide a basin-wide ecological baseline and improve understanding of how coastal urbanization and geographic gradients can shape marine invasion dynamics. Abundance Balearic Islands coastal urbanization Crete crustacean exotic species Gulf of Naples herbivore Iberian Peninsula non-native Percnon gibbesi rocky habitat Sicily spider crab Full Text Supplementary Files AntonetalData.pdf Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revise and Resubmit 09 Apr, 2026 Reviewers agreed at journal 19 Jan, 2026 Reviewers invited by journal 13 Jan, 2026 Editor assigned by journal 09 Jan, 2026 First submitted to journal 08 Jan, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8523331","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":573717172,"identity":"bf2d3a44-8d30-4aef-afbe-de771e19b15f","order_by":0,"name":"Andrea Anton","email":"data:image/png;base64,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","orcid":"https://orcid.org/0000-0002-4104-2966","institution":"IMEDEA: Institut Mediterrani d'Estudis Avancats","correspondingAuthor":true,"prefix":"","firstName":"Andrea","middleName":"","lastName":"Anton","suffix":""},{"id":573717173,"identity":"ebdfea19-c2f3-440f-9a1e-240f96a0c691","order_by":1,"name":"Xavier Bachot","email":"","orcid":"","institution":"IMEDEA: Institut Mediterrani d'Estudis Avancats","correspondingAuthor":false,"prefix":"","firstName":"Xavier","middleName":"","lastName":"Bachot","suffix":""},{"id":573717174,"identity":"5bc21deb-09e5-4044-9dca-75ec86080347","order_by":2,"name":"Maria Pizarro-Borrull","email":"","orcid":"","institution":"IMEDEA: Institut Mediterrani d'Estudis Avancats","correspondingAuthor":false,"prefix":"","firstName":"Maria","middleName":"","lastName":"Pizarro-Borrull","suffix":""},{"id":573717175,"identity":"764dde58-13f7-4fea-81be-d45cdc21c35d","order_by":3,"name":"Sara Muñiz-Quintana","email":"","orcid":"","institution":"IMEDEA: Institut Mediterrani d'Estudis Avancats","correspondingAuthor":false,"prefix":"","firstName":"Sara","middleName":"","lastName":"Muñiz-Quintana","suffix":""},{"id":573717176,"identity":"ccd8f768-271a-4799-aedd-ad2e4c0e802b","order_by":4,"name":"Daniel B. Puentes","email":"","orcid":"","institution":"IMEDEA: Institut Mediterrani d'Estudis Avancats","correspondingAuthor":false,"prefix":"","firstName":"Daniel","middleName":"B.","lastName":"Puentes","suffix":""}],"badges":[],"createdAt":"2026-01-05 16:18:14","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8523331/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8523331/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":100251797,"identity":"87d9d9ab-03de-46b4-8d55-9b5a87e6214c","added_by":"auto","created_at":"2026-01-14 15:09:30","extension":"xml","order_by":1,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":11791,"visible":true,"origin":"","legend":"","description":"","filename":"mabiMABID2600009.xml","url":"https://assets-eu.researchsquare.com/files/rs-8523331/v1/5897080545a32a513ce4c05f.xml"},{"id":100251765,"identity":"cd40cee8-8cd1-4af8-a0c6-375e20da183f","added_by":"auto","created_at":"2026-01-14 15:09:26","extension":"xml","order_by":2,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":969,"visible":true,"origin":"","legend":"","description":"","filename":"MABID260000915048.go.xml","url":"https://assets-eu.researchsquare.com/files/rs-8523331/v1/eeaeffaca73a408c978785a1.xml"},{"id":100251766,"identity":"410c0820-077d-4fc3-9411-f17bae4e3247","added_by":"auto","created_at":"2026-01-14 15:09:26","extension":"xml","order_by":3,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":858,"visible":true,"origin":"","legend":"","description":"","filename":"MABID2600009Import.xml","url":"https://assets-eu.researchsquare.com/files/rs-8523331/v1/b3a1bf86adf32837ad6c6cd9.xml"},{"id":100251805,"identity":"ea311758-4c80-4a64-bab4-53ebad2df373","added_by":"auto","created_at":"2026-01-14 15:09:44","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2601572,"visible":true,"origin":"","legend":"","description":"","filename":"Antonetalms.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8523331/v1_covered_dbabcb6b-9dbc-4d6b-9a07-88fcf8fe8b81.pdf"},{"id":100251770,"identity":"173dffa3-2e0e-4c34-b4db-216f9db9aba5","added_by":"auto","created_at":"2026-01-14 15:09:26","extension":"pdf","order_by":4,"title":"","display":"","copyAsset":false,"role":"supplement","size":144197,"visible":true,"origin":"","legend":"","description":"","filename":"AntonetalData.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8523331/v1/afd006647be08fb75eb3d48e.pdf"}],"financialInterests":"","formattedTitle":"Basin-wide patterns of abundance of a widespread invasive herbivore in the Mediterranean Sea","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"marine-biology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"mabi","sideBox":"Learn more about [Marine Biology](https://www.springer.com/journal/227)","snPcode":"227","submissionUrl":"https://submission.nature.com/new-submission/227/3","title":"Marine Biology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Abundance, Balearic Islands, coastal urbanization, Crete, crustacean, exotic species, Gulf of Naples, herbivore, Iberian Peninsula, non-native, Percnon gibbesi, rocky habitat, Sicily, spider crab","lastPublishedDoi":"10.21203/rs.3.rs-8523331/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8523331/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"Biological invasions continue to accumulate globally, yet basic ecological information is lacking for many widespread marine non-native species. The tropical–subtropical herbivorous crab Percnon gibbesi has expanded rapidly throughout the Mediterranean basin but quantitative assessments of its abundance remain geographically limited. This knowledge gap is particularly relevant given the demonstrated capacity of the species to heavily graze macrophytes under laboratory conditions and the rapid proliferation of artificial coastal structures that may further enhance its abundance. To address these gaps, we quantified P. gibbesi densities at 79 sites across the Mediterranean Basin, encompassing both natural rocky habitats and artificial hard substrates. On average, P. gibbesi was nearly twice as abundant on artificial structures as on natural substrates, and its abundance increased towards the eastern Mediterranean. Although mean densities were high (36.2 individuals per 100 m²), abundance varied markedly among sites and regions, suggesting that - assuming a positive relationship between abundance and impact - the ecological impacts of this invader are likely to be highly heterogeneous across Mediterranean landscapes. Together, these findings provide a basin-wide ecological baseline and improve understanding of how coastal urbanization and geographic gradients can shape marine invasion dynamics.","manuscriptTitle":"Basin-wide patterns of abundance of a widespread invasive herbivore in the Mediterranean Sea","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-01-14 15:08:55","doi":"10.21203/rs.3.rs-8523331/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revise and Resubmit","date":"2026-04-10T03:19:45+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"","date":"2026-01-19T15:09:22+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-01-13T07:16:08+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-01-09T14:53:04+00:00","index":"","fulltext":""},{"type":"submitted","content":"Marine Biology","date":"2026-01-09T03:17:54+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"marine-biology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"mabi","sideBox":"Learn more about [Marine Biology](https://www.springer.com/journal/227)","snPcode":"227","submissionUrl":"https://submission.nature.com/new-submission/227/3","title":"Marine Biology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"426532eb-70d0-4e46-ac0c-579658c62c55","owner":[],"postedDate":"January 14th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"in-revision","subjectAreas":[],"tags":[],"updatedAt":"2026-04-10T07:42:50+00:00","versionOfRecord":[],"versionCreatedAt":"2026-01-14 15:08:55","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8523331","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8523331","identity":"rs-8523331","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}