ARCHIVED - Giant wels catfish caught in the River Guadalquivir near Sevilla
A wels catfish is reported to have devoured a fox terrier in the province of Cáceres
The huge wels catfish has been illegally introduced to Spanish rivers to encourage angling tourism
Images: Archive, not the example caught on this occasion
Suspicions that the monstruous wels catfish, the largest species of true freshwater fish in the world, has reached the Guadalquivir river in Andalucía, have finally been confirmed this week following the capture of a specimen close to Alcalá del Río, around 10 kilometres north of the city of Sevilla.
The wels catfish (Silurus glanis) can grow to lengths of up to 3 metres and weigh well over 100 kilos, and is known to eat ducks and doves to supplement its usual diet of worms, gastropods, insects, crustaceans, and fish. It can also be cannibalistic and specimens have been observed lunging out of the water to feed on pigeons on land (a technique known as “beaching”), but while it is nicknamed the “European maneater” by some no human deaths have been definitively attributed to the species.
Nonetheless, stories regarding attacks by the wels catfish regularly appear in tabloid newspapers, and one of these stories was investigated by naturalist Jeremy Wade in an episode of his television series “River Monsters”. During the episode, Wade travels to Spain, where a group of wels catfish were introduced years ago into the River Ebro and have since taken over the ecosystem, possibly due to the “catch and release” policy of sporting anglers.
The catch in Alcalá del Río has been confirmed by both Ecologistas en Acción and zoologists at the University of Córdoba, confirming that the habitat of the species in Andalucía is no longer limited to the reservoir of Iznájar, where it was introduced in similar a fashion to the scheme in the Ebro in 2011 in an attempt to generate fishing tourism. This initiative was not legally authorized but the fish have been protected by the regional government and no elimination campaign has been set in motion.
The specimen found in Alcalá is not believed to have escaped from Iznájar and Ecologistas en Acción believe that its presence is the consequence of another act of environmental irresponsibility. The group also reports wels catfish having been caught in the reservoir of Gergal, which is fed by the Rivera de Huelva river, and residents of Tiétar in Cáceres claim that a catfish recently devoured a fox terrier. The species has been spotted in the reservoirs of Aracena and Zufre in the north of the province of Huelva, but in the River Guadalquivir the fear is that it may extend its territory further downstream, threatening both the important bio-diversity of the area - including plants and wading birds as well as other fish species - and the commercial fishing and fish-farming activities which are permitted there.