Surfing on vortices: Bird flight responses to an unsteady vortex wake

Surfing on vortices: Bird flight responses to an unsteady vortex wake | 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 Surfing on vortices: Bird flight responses to an unsteady vortex wake Siyang Hao, Noah Medina, Mareesa Islam, Ronan Gissler, Tyson Hedrick, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8689655/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 11 You are reading this latest preprint version Abstract We report on results from wind tunnel experiments examining the flight of European starlings (\emph{Sturnus vulgaris}) in both steady flows and in the presence of a structured vortex wake generated by a pitching airfoil. The investigation employs synchronized high-speed kinematic tracking alongside time-resolved Particle Image Velocimetry (PIV) to assess the birds' flight mechanics and interactions with unsteady flow. When flying in the presence of a vortex wake, the starlings exhibited distinct kinematic adjustments relative to their trajectories in clean steady flow. The wake footprints observed through PIV corroborated the kinematic measurements, revealing a phase alignment between the birds’ wingbeats and the periodic wake background.The combined circulation, resulting from the merging of the bird's flapping wake and the mechanically generated wake, closely resembles an in-phase superposition of the two components in the non-interactive cases. Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 27 Apr, 2026 Reviews received at journal 17 Apr, 2026 Reviews received at journal 09 Mar, 2026 Reviews received at journal 18 Feb, 2026 Reviewers agreed at journal 09 Feb, 2026 Reviewers agreed at journal 08 Feb, 2026 Reviewers agreed at journal 08 Feb, 2026 Reviewers invited by journal 02 Feb, 2026 Editor assigned by journal 02 Feb, 2026 Submission checks completed at journal 26 Jan, 2026 First submitted to journal 24 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. 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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-8689655","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":584220724,"identity":"4aad4625-c248-4ad6-be51-91c765053bfd","order_by":0,"name":"Siyang 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