{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,27]],"date-time":"2026-03-27T07:16:16Z","timestamp":1774595776951,"version":"3.50.1"},"reference-count":41,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2022,10,7]],"date-time":"2022-10-07T00:00:00Z","timestamp":1665100800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union, the Russian Federation and the Republic of Finland","award":["KS1549"],"award-info":[{"award-number":["KS1549"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Wildlife camera traps and crowd-sourced image material provide novel possibilities to monitor endangered animal species. The massive data volumes call for automatic methods to solve various tasks related to population monitoring, such as the re-identification of individual animals. The Saimaa ringed seal (Pusa hispida saimensis) is an endangered subspecies only found in Lake Saimaa, Finland, and is one of the few existing freshwater seal species. Ringed seals have permanent pelage patterns that are unique to each individual and that can be used for the identification of individuals. A large variation in poses, further exacerbated by the deformable nature of seals, together with varying appearance and low contrast between the ring pattern and the rest of the pelage makes the Saimaa ringed seal re-identification task very challenging, providing a good benchmark by which to evaluate state-of-the-art re-identification methods. Therefore, we make our Saimaa ringed seal image (SealID) dataset (N = 57) publicly available for research purposes. In this paper, the dataset is described, the evaluation protocol for re-identification methods is proposed, and the results for two baseline methods\u2014HotSpotter and NORPPA\u2014are provided. The SealID dataset has been made publicly available.<\/jats:p>","DOI":"10.3390\/s22197602","type":"journal-article","created":{"date-parts":[[2022,10,10]],"date-time":"2022-10-10T05:12:21Z","timestamp":1665378741000},"page":"7602","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["SealID: Saimaa Ringed Seal Re-Identification Dataset"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5045-5041","authenticated-orcid":false,"given":"Ekaterina","family":"Nepovinnykh","sequence":"first","affiliation":[{"name":"Computer Vision and Pattern Recognition Laboratory (CVPRL), Department of Computational Engineering, Lappeenranta\u2013Lahti University of Technology, 53850 Lappeenranta, Finland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1352-0999","authenticated-orcid":false,"given":"Tuomas","family":"Eerola","sequence":"additional","affiliation":[{"name":"Computer Vision and Pattern Recognition Laboratory (CVPRL), Department of Computational Engineering, Lappeenranta\u2013Lahti University of Technology, 53850 Lappeenranta, Finland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1885-0946","authenticated-orcid":false,"given":"Vincent","family":"Biard","sequence":"additional","affiliation":[{"name":"Department of Environmental and Biological Sciences, University of Eastern Finland, 80101 Joensuu, Finland"}]},{"given":"Piia","family":"Mutka","sequence":"additional","affiliation":[{"name":"Department of Environmental and Biological Sciences, University of Eastern Finland, 80101 Joensuu, Finland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1516-8346","authenticated-orcid":false,"given":"Marja","family":"Niemi","sequence":"additional","affiliation":[{"name":"Department of Environmental and Biological Sciences, University of Eastern Finland, 80101 Joensuu, Finland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3612-8842","authenticated-orcid":false,"given":"Mervi","family":"Kunnasranta","sequence":"additional","affiliation":[{"name":"Department of Environmental and Biological Sciences, University of Eastern Finland, 80101 Joensuu, Finland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0790-6847","authenticated-orcid":false,"given":"Heikki","family":"K\u00e4lvi\u00e4inen","sequence":"additional","affiliation":[{"name":"Computer Vision and Pattern Recognition Laboratory (CVPRL), Department of Computational Engineering, Lappeenranta\u2013Lahti University of Technology, 53850 Lappeenranta, Finland"}]}],"member":"1968","published-online":{"date-parts":[[2022,10,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"108908","DOI":"10.1016\/j.biocon.2020.108908","article-title":"Sealed in a lake\u2014Biology and conservation of the endangered Saimaa ringed seal: A review","volume":"253","author":"Kunnasranta","year":"2021","journal-title":"Biol. 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