{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T12:13:34Z","timestamp":1784031214519,"version":"3.55.0"},"reference-count":44,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2025,11,4]],"date-time":"2025-11-04T00:00:00Z","timestamp":1762214400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Free-roaming domestic cats (Felis catus) present a major management challenge for animal welfare and biodiversity conservation. Trap-neuter-return (TNR) programs, which include sterilization and return of cats, are increasingly adopted to manage cat populations, often alongside routine food provisioning. However, their effectiveness in reducing cats\u2019 reliance on wild prey remains contested. In this study, we use stable isotope analysis (\u03b413C, \u03b415N, \u03b434S) of cat fur to investigate dietary patterns before and after TNR implementation in the context of concurrent changes in food availability linked to the closure of nearby mink-farming operations. We analyzed samples from 122 cats in a large-scale TNR initiative on a rural property in British Columbia, Canada. These included indoor cats (control), free-roaming cats prior to TNR (Group 1), a subset of Group 1 re-sampled months after food provisioning began (Run 2), and newly sampled cats that had been fed regularly before trapping (Group 2). Local prey and food sources were also analyzed to provide a comparative isotopic baseline. Our results show clear dietary shifts following TNR. Group 1 cats exhibited high isotopic variability and elevated \u03b415N and \u03b434S values, consistent with wild prey consumption. In contrast, post-TNR cats showed significantly lower and more homogeneous values, aligning closely with those of indoor, kibble-fed cats. These changes are consistent with a reduced dietary reliance on wildlife and raw mink feed following the combination of TNR with regular provisioning and the cessation of mink operations. These findings demonstrate that regular food provisioning in TNR-managed colonies, particularly when combined with broader environmental changes, can significantly alter cat diets and potentially reduce their dependence on wild prey.<\/jats:p>","DOI":"10.3390\/ani15213204","type":"journal-article","created":{"date-parts":[[2025,11,4]],"date-time":"2025-11-04T11:11:16Z","timestamp":1762254676000},"page":"3204","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Evaluating the Effects of Managed Free-Roaming Cat Populations on Prey Through Stable Isotope Analysis: A Pilot Study from British Columbia, Canada"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6197-2450","authenticated-orcid":false,"given":"Valentina","family":"Martinoia","sequence":"first","affiliation":[{"name":"Faculty of Medicine, University of Udine, P.le Kolbe 3, 33100 Udine, Italy"},{"name":"Faculty of Environment, Simon Fraser University, 8888 University Dr., Burnaby, BC V5A 1S6, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Renee","family":"Ferguson","sequence":"additional","affiliation":[{"name":"TinyKittens Society, Fort Langley, BC V1M 2S2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3642-5911","authenticated-orcid":false,"given":"Peter J.","family":"Wolf","sequence":"additional","affiliation":[{"name":"Best Friends Animal Society, 5001 Angel Canyon Road, Kanab, UT 84741, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mario","family":"Cari\u0107","sequence":"additional","affiliation":[{"name":"Center for Applied Bioanthropology, Institute for Anthropological Research, Ljudevita Gaja 32, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4567-8742","authenticated-orcid":false,"given":"Mario","family":"Novak","sequence":"additional","affiliation":[{"name":"Center for Applied Bioanthropology, Institute for Anthropological Research, Ljudevita Gaja 32, 10000 Zagreb, Croatia"},{"name":"Faculty of Humanities, University of Primorska, Titov trg 5, 6000 Koper, Slovenia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shelly","family":"Roche","sequence":"additional","affiliation":[{"name":"TinyKittens Society, Fort Langley, BC V1M 2S2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Aeluro, S., Buchanan, J.M., Boone, J.D., and Rabinowitz, P.M. 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