{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T12:26:19Z","timestamp":1777379179059,"version":"3.51.4"},"reference-count":45,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2021,11,22]],"date-time":"2021-11-22T00:00:00Z","timestamp":1637539200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["No. 2018YFC1406906"],"award-info":[{"award-number":["No. 2018YFC1406906"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Long-term observation of penguin abundance and distribution may warn of changes in the Antarctic marine ecosystem and provide support for penguin conservation. We conducted an unmanned aerial vehicle (UAV) survey of the Ad\u00e9lie penguin (Pygoscelis adeliae) colony on Inexpressible Island and obtained aerial images with a resolution of 0.07 m in 2018. We estimated penguin abundance and identified the spatial extent of the penguin colony. A total of 24,497 breeding pairs were found on Inexpressible Island within a colony area of 57,507 m2. Based on historical images, the colony area expanded by 30,613 m2 and abundance increased by 4063 pairs between 1983 and 2012. Between 2012 and 2018 penguin abundance further increased by 3314 pairs, although the colony area decreased by 1903 m2. In general, Ad\u00e9lie penguins bred on Inexpressible Island at an elevation &lt;20 m, and &gt;55% of penguins had territories within 150 m of the shoreline. This suggests that penguins prefer to breed in areas with a low elevation and close to the shoreline. We observed a retreat of the shoreline on Inexpressible Island between 1983 and 2018, especially along the northern coast, which may have played a key role in the expansion of the penguin colony on the northern coast. In sum, it appears that retreating shorelines reshaped penguin distribution on the island and may be an emerging risk factor for penguins. These results highlight the importance of remote sensing techniques for monitoring changes in the Antarctic marine ecosystem and providing reliable data for Antarctic penguin conservation.<\/jats:p>","DOI":"10.3390\/rs13224718","type":"journal-article","created":{"date-parts":[[2021,12,1]],"date-time":"2021-12-01T01:45:02Z","timestamp":1638323102000},"page":"4718","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Retreating Shorelines as an Emerging Threat to Ad\u00e9lie Penguins on Inexpressible Island"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4774-6841","authenticated-orcid":false,"given":"Xintong","family":"Chen","sequence":"first","affiliation":[{"name":"State Key Laboratory of Remote Sensing Science and College of Global Change and Earth System Science, Beijing Normal University, Beijing 100875, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0761-9458","authenticated-orcid":false,"given":"Jiquan","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Geography, Environment, and Spatial Science, Michigan State University, East Lansing, MI 48823, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6910-6565","authenticated-orcid":false,"given":"Xiao","family":"Cheng","sequence":"additional","affiliation":[{"name":"School of Geospatial Engineering and Science, Sun Yat-Sen University and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519000, China"},{"name":"University Corporation for Polar Research, Beijing 100875, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lizhong","family":"Zhu","sequence":"additional","affiliation":[{"name":"Heilongjiang Bureau of Surveying and Mapping Geographic Information, Harbin 150081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bing","family":"Li","sequence":"additional","affiliation":[{"name":"Heilongjiang Geomatics Center of NASG, Harbin 150081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xianglan","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Remote Sensing Science and College of Global Change and Earth System Science, Beijing Normal University, Beijing 100875, China"},{"name":"University Corporation for Polar Research, Beijing 100875, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"457","DOI":"10.1642\/AUK-14-31.1","article-title":"First global census of the Ad\u00e9lie Penguin","volume":"131","author":"Lynch","year":"2014","journal-title":"Auk"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Ainley, D. 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