On the establishment and range expansion of oriental weatherfish (Misgurnus anguillicaudatus) in NE Iberian Peninsula

Oriental weatherfish has become an invasive fish species in many temperate areas. In this work we report the presence of an established weatherfish population in northeastern Iberian Peninsula and describe, for the first time in Europe, a clear range expansion. The species was first located in the Ebro River Delta in 2001 and has since been detected in 31 UTM 1 x 1 km quadrates. The capture of over 1,000 weatherfish shows that its population is composed by both juvenile and adult individuals. Weatherfish occupies mostly the web of irrigation channels associated with rice culture, although it has also been detected in rice fields and in the Ebro River. The expansion of the species in the area seems to be limited by water conductivity. An additional location for the species in the Ter basin (some 300 km to the north) suggests that inter-basin expansion could be occurring. This new fish invasion reinforces the need to implement strict controls to the trade and culture of ornamental fish.