American bullfrogs (Lithobates catesbeianus) are large frogs originally from the eastern United States, meaning that in California, they’re considered an invasive species. Northwestern pond turtles (Actinemys marmorata) are one of only two native freshwater turtles in California, and they have seen a particularly dramatic population decline. Low and behold, when the researchers had almost completely eliminated the invasive species from both sites, baby northwestern pond turtles made a comeback. “Invasive species can outcompete and eliminate desirable native species and cause declines in many endangered species. Invasive species can even damage human livelihoods by affecting crops or domesticated animals and they can spread diseases.”