Asian swamp eels in North America linked to the live-food trade and prayer-release rituals

We provide a history of swamp eel (family Synbranchidae) introductions around the globe and report the first confirmed nonindigenous records of Amphipnous cuchia in the wild. The species, native to Asia, is documented from five sites in the USA: the Passaic River, New Jersey (2007), Lake Needwood, Maryland (2014), a stream in Pennsylvania (2015), the Tittabawassee River, Michigan (2017), and Meadow Lake, New York (2017). The international live-food trade constitutes the major introduction pathway, a conclusion based on: (1) United States Fish and Wildlife Service’s Law Enforcement Management Information System (LEMIS) database records revealing regular swamp eel imports from Asia since at least the mid-1990s; (2) surveys (2001–2018) documenting widespread distribution of live A. cuchia among ethnic food markets in the USA and Canada; (3) indications that food markets are the only source of live A. cuchia in North America; and (4) presence of live A. cuchia in markets close to introduction sites. Prayer release appears to be an important pathway component, whereby religious practitioners purchase live A. cuchia from markets and set them free. Prevalence of A. cuchia in US markets since 2001 indicates the species is the principal swamp eel imported, largely replacing members of the Asian complex Monopterus albus/javanensis. LEMIS records (July 1996–January 2017) document 972 shipments containing an estimated 832,897 live swamp eels entering the USA, although these data underestimate actual numbers due to undeclared and false reporting. LEMIS data reveal most imports originate in Bangladesh, Vietnam, and China. However, LEMIS wrongly identifies many imported swamp eels as “Monopterus albus”; none are identified as A. cuchia although specimens from Bangladesh and India are almost certainly this species. Some imported A. cuchia are erroneously declared on import forms as Anguilla bengalensis. To date, there is no evidence of A. cuchia reproduction in open waters of North America, presumably because it is a tropical-subtropical species and all introductions thus far have been in latitudes where winter water temperatures regularly fall near or below freezing.