Sub-Saharan frogs in the temperate Pacific Northwestern United States? A recent synthesis by Emmenegger and 22 colleagues (2025) show that, for the past 10 years, scientists and practitioners in the Puget Sound area of Washington state have been tracking multiple populations of African Clawed Frogs (Xenopus laevis). In Washington, African Clawed Frogs have been discovered in three different watersheds that have no hydrologic connection and so likely were introduced multiple independent times. Although currently banned in the pet trade in Washington, they are still used in research and were historically common pets in the state. Clawed Frogs in Washington are found in a diversity of waterbodies ranging from constructed stormwater ponds to salmon-baring streams and a lake. The impacts of these frogs are unclear although they could mobilize pathogens and prey upon a diversity of native species ranging from invertebrates to fishes and other amphibians. Management in Washington has been woefully unsuccessful; a range of intensive and innovative trapping as well salting ponds has failed to eradicate the frogs locally from any waterbody. In fact, intensive removal of adults had allowed for cannibalism relief on Clawed Frog tadpoles and a rebound of the population the following year and the frogs consistently survive beneath ice despite their tropical origins. The exact threats and management strategies for African Clawed Frogs in the Pacific Northwestern U.S. continue to remain a challenge posed by introduced species.

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