Climatic niche dynamics in the invasive nutria, Myocastor coypus: global assessment under climate change

Nutria, Myocastor coypus, native to South America, is one of the world's worst invasive mammals, having major ecological and economic consequences. We evaluated the realized climatic niches of nutria in their native and invasive regions (Africa, Asia, Europe, and North America) to investigate whether niche changes occurred during their invasion, as well as to assess the extent of niche conservatism and environmental equilibrium. We also explored current and future potential distributions of nutria under climate change. Based on niche equivalence and similarity tests, niches with moderate to high overlap were conserved in Western Asia, Europe, and North America, whereas niches with zero to low overlap in East Asia and Africa were shifted. Nutria showed high niche stability and low niche expansion across Africa, Europe, and North America. The high level of unfilled niches suggests great potential for further expansion into East Asia, Europe, and Africa. Asia, on the other hand, has shown the greatest niche occupancy in non-native ranges. In 2070, nutria habitat conditions were predicted to expand in Western Asia, Europe, and North America towards higher latitudes, while their southern ranges contracted. Also, ensemble models indicate that areas in Southern Australia and Oceania where nutria are not known to occur are well suited for their colonization. The results of this study provide valuable insight into the nutria's niche dynamics as well as its current and future distribution status on a global scale, suggesting that it may adapt to a wide range of environments.