India, Oct. 23 -- In 2017, a pregnant female nutria was captured in a private wetland near Gustine in Merced County, California. The California Department of Fish and Wildlife says nutria had been declared eradicated from the state by 1978, with no reported detections between then and their rediscovery. During the summer of 2017, officials captured 19 additional nutria in the Grasslands Ecological Area.

A 2025 study published in Evolutionary Applications found that California's current nutria population was genetically most similar to invasive nutria in central Oregon. The findings suggest a recent introduction followed by rapid spread, although the genetic evidence cannot establish the precise route by which the animals reached Californ...