{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T05:05:46Z","timestamp":1787029546135,"version":"3.56.0"},"reference-count":58,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2021,8,24]],"date-time":"2021-08-24T00:00:00Z","timestamp":1629763200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000199","name":"U.S. Department of Agriculture","doi-asserted-by":"publisher","award":["AP20WSNWRC00C010 and AP20WSNWRC00C026"],"award-info":[{"award-number":["AP20WSNWRC00C010 and AP20WSNWRC00C026"]}],"id":[{"id":"10.13039\/100000199","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In recent years, small unmanned aircraft systems (sUAS) have been used widely to monitor animals because of their customizability, ease of operating, ability to access difficult to navigate places, and potential to minimize disturbance to animals. Automatic identification and classification of animals through images acquired using a sUAS may solve critical problems such as monitoring large areas with high vehicle traffic for animals to prevent collisions, such as animal-aircraft collisions on airports. In this research we demonstrate automated identification of four animal species using deep learning animal classification models trained on sUAS collected images. We used a sUAS mounted with visible spectrum cameras to capture 1288 images of four different animal species: cattle (Bos taurus), horses (Equus caballus), Canada Geese (Branta canadensis), and white-tailed deer (Odocoileus virginianus). We chose these animals because they were readily accessible and white-tailed deer and Canada Geese are considered aviation hazards, as well as being easily identifiable within aerial imagery. A four-class classification problem involving these species was developed from the acquired data using deep learning neural networks. We studied the performance of two deep neural network models, convolutional neural networks (CNN) and deep residual networks (ResNet). Results indicate that the ResNet model with 18 layers, ResNet 18, may be an effective algorithm at classifying between animals while using a relatively small number of training samples. The best ResNet architecture produced a 99.18% overall accuracy (OA) in animal identification and a Kappa statistic of 0.98. The highest OA and Kappa produced by CNN were 84.55% and 0.79 respectively. These findings suggest that ResNet is effective at distinguishing among the four species tested and shows promise for classifying larger datasets of more diverse animals.<\/jats:p>","DOI":"10.3390\/s21175697","type":"journal-article","created":{"date-parts":[[2021,8,24]],"date-time":"2021-08-24T22:09:39Z","timestamp":1629842979000},"page":"5697","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":39,"title":["Improving Animal Monitoring Using Small Unmanned Aircraft Systems (sUAS) and Deep Learning Networks"],"prefix":"10.3390","volume":"21","author":[{"given":"Meilun","family":"Zhou","sequence":"first","affiliation":[{"name":"Geosystems Research Institute, Mississippi State University, Oxford, MS 39762, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5980-1561","authenticated-orcid":false,"given":"Jared A.","family":"Elmore","sequence":"additional","affiliation":[{"name":"Department of Wildlife, Fisheries and Aquaculture, Mississippi State University, Box 9690, Oxford, MS 39762, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8443-883X","authenticated-orcid":false,"given":"Sathishkumar","family":"Samiappan","sequence":"additional","affiliation":[{"name":"Geosystems Research Institute, Mississippi State University, Oxford, MS 39762, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kristine O.","family":"Evans","sequence":"additional","affiliation":[{"name":"Department of Wildlife, Fisheries and Aquaculture, Mississippi State University, Box 9690, Oxford, MS 39762, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Morgan B.","family":"Pfeiffer","sequence":"additional","affiliation":[{"name":"U.S. Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, National Wildlife Research Center, Ohio Field Station, Sandusky, OH 44870, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bradley F.","family":"Blackwell","sequence":"additional","affiliation":[{"name":"U.S. Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, National Wildlife Research Center, Ohio Field Station, Sandusky, OH 44870, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raymond B.","family":"Iglay","sequence":"additional","affiliation":[{"name":"Department of Wildlife, Fisheries and Aquaculture, Mississippi State University, Box 9690, Oxford, MS 39762, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,24]]},"reference":[{"key":"ref_1","unstructured":"Dolbeer, R.A., Begier, M.J., Miller, P.R., Weller, J.R., and Anderson, A.L. 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