A newly published study by California Department of Fish and Wildlife scientists offers the clearest picture yet of how nutria — a destructive, invasive rodent — reappeared in California after being declared eradicated decades ago. Using advanced genomic analysis, researchers determined that nutria discovered in Merced County in 2017 are most closely linked to a population in central Oregon, rather than descendants of animals believed wiped out in California in the 1970s. … Nutria can eat up to 25% of their body weight in plants each day, and their feeding often destroys far more vegetation than they consume, leading to erosion that can permanently convert marshland into open water.

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• The Independent (U.K.): Giant rodent that could devastate California wetlands was ‘deliberately’ reintroduced to population, experts fear​