Mylène Dutour (@dutourmylene.bsky.social)

An updated estimate of the number of birds killed by outdoor cats in Canada - Avian Conservation and Ecology Domestic cats, Felis catus, can be found almost everywhere in the world and estimating their impact on wildlife, including birds, requires the most up-to-date information. There are an estimated 9.3 million pet cats in Canada, 30–60% of which are given unrestricted access to the outdoors. With the best available data in 2013, cats were estimated to kill between 105–348 million birds per year in Canada, making them the leading measurable cause of bird mortality in the country. However, a decade later, research on outdoor cats and their predation of birds has increased considerably, providing an opportunity to revisit this mortality estimate. Using recent data on predation rates and cat abundance, we estimated that cats kill between 19 and 197 million birds per year in Canada, 71% lower than the earlier estimate. This does not mean that cat populations or predation rates on birds have declined since the previous estimate. Rather, we suggest that the difference can be primarily attributed to lower outdoor cat abundance estimated from field surveys compared to previously used cat ownership surveys and media reports of shelter intake data. Although the estimated number of birds killed annually by cats is considerably lower than the previous estimate, outdoor cats remain a serious concern for native bird populations. https://ace-eco.org/vol20/iss2/art12/