{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,24]],"date-time":"2026-07-24T22:10:54Z","timestamp":1784931054221,"version":"3.55.0"},"reference-count":68,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2025,6,25]],"date-time":"2025-06-25T00:00:00Z","timestamp":1750809600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"German Association of Zoological Gardens (Verband der Zoologischen G\u00e4rten e.V, VdZ)"},{"name":"Veterinary Association for Animal Welfare (Tier\u00e4rztliche Vereinigung f\u00fcr Tierschutz eV)"},{"name":"Freie Universit\u00e4t Berlin"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Flight is part of the natural behaviours of most bird species, and as a consequence, flight restraint in zoos, even for those species that are primarily ground-dwelling, encounters increasing animal welfare concerns. While previous studies on greater flamingos (Phoenicopterus roseus) and white pelicans (Pelecanus onocrotalus) have found no significant effects of flight restraint on welfare, scientific data on other species remains limited. This study investigated the welfare implications of flight restraint in white storks (Ciconia ciconia) by assessing feather corticosterone concentrations (CORTf) alongside behavioural observations. We compared CORTf values of deflighted zoo birds (n = 53) and hand-reared abandoned nestlings (n = 11) from eleven different zoos in Germany and storks in rehabilitation. These birds were wild individuals, found injured, and therefore provided an opportunity to collect feather samples (n = 70). In line with the 3R principle proposed by Russell and Burch, we employed a recently validated, less invasive feather sampling method that involves cutting feathers close to the skin. We hypothesised that CORTf would differ significantly between the wild, airworthy storks and the deflighted individuals under human care. However, we found no significant difference in CORTf regarding the ability to fly, nor did the method of flight restraint show a significant influence on CORTf. Housing facilities with significant site-specific variations emerged as the predominant factor influencing feather corticosterone concentrations. These results suggest that flight restraint does not have a noticeable direct impact on the corticosterone levels of white storks, and the behavioural observations support the reliability of these findings. This study enhances our understanding of the effects of deflighting procedures on the welfare of white storks in zoos.<\/jats:p>","DOI":"10.3390\/ani15131878","type":"journal-article","created":{"date-parts":[[2025,6,26]],"date-time":"2025-06-26T03:39:59Z","timestamp":1750909199000},"page":"1878","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Effects of Flight Restraint and Housing Conditions on Feather Corticosterone in White Storks Under Human Care"],"prefix":"10.3390","volume":"15","author":[{"given":"Frederike","family":"Liermann","sequence":"first","affiliation":[{"name":"Animal Behaviour and Laboratory Animal Science, Institute of Animal Welfare, Freie Universit\u00e4t Berlin, K\u00f6nigsweg 67, D-14163 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katrin","family":"Baumgartner","sequence":"additional","affiliation":[{"name":"Zoo Nuremberg, Am Tiergarten 30, D-90480 Nuremberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6083-0394","authenticated-orcid":false,"given":"Ralph","family":"Simon","sequence":"additional","affiliation":[{"name":"Zoo Nuremberg, Am Tiergarten 30, D-90480 Nuremberg, Germany"},{"name":"Machine Learning and Data Analytics Lab, Department Artificial Intelligence in Biomedical Engineering (AIBE), Friedrich-Alexander-Universit\u00e4t Erlangen-N\u00fcrnberg (FAU), Carl-Thiersch-Stra\u00dfe 2b, D-91052 Erlangen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hermann","family":"Will","sequence":"additional","affiliation":[{"name":"Zoo Nuremberg, Am Tiergarten 30, D-90480 Nuremberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3451-0530","authenticated-orcid":false,"given":"Lorenzo","family":"von Fersen","sequence":"additional","affiliation":[{"name":"Zoo Nuremberg, Am Tiergarten 30, D-90480 Nuremberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8688-2926","authenticated-orcid":false,"given":"Roswitha","family":"Merle","sequence":"additional","affiliation":[{"name":"Institute of Veterinary Epidemiology and Biostatistics, Freie Universit\u00e4t Berlin, K\u00f6nigsweg 67, D-14163 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0782-2755","authenticated-orcid":false,"given":"Christa","family":"Th\u00f6ne-Reineke","sequence":"additional","affiliation":[{"name":"Animal Behaviour and Laboratory Animal Science, Institute of Animal Welfare, Freie Universit\u00e4t Berlin, K\u00f6nigsweg 67, D-14163 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"293","DOI":"10.1016\/j.zoolgart.2014.01.004","article-title":"Flugunf\u00e4higmachen von V\u00f6geln\u2013F\u00fcr und Wider","volume":"82","author":"Dollinger","year":"2013","journal-title":"Der Zoologische Garten Zeitschrift f\u00fcr die Gesamte Tierg\u00e4rtnerei"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Haase, G., Baumgartner, K., von Fersen, L., Merle, R., Wiegard, M., Will, H., Reese, L., Tallo-Parra, O., Carbajal, A., and Lopez-Bejar, M. 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