New pike species doing too well in Italy
17 January 2012
Researchers working in Italy including Dr Diego Fontaneto (Life Sciences) have called for wildlife managers to stop relocating freshwater pike from European countries north of the Alps to Italian freshwaters, where they are caught by anglers. This follows the discovery that fish from these geographically separate regions belong to two distinct species – they were previously thought to have been members of the same species.
Pike are easily recognisable by their elongated torpedo-like body shape and are a popular choice for anglers across Europe, North America and Asia. Heavy fishing has caused populations to dwindle in some areas, a problem that is being solved by replacing them with juvenile fish from more healthy populations.
The researchers have called to ban this practice in Italy, since the northern pike species native to central and northern Europe is potentially in danger of driving the native southern pike species to extinction.
Until now only one species of pike was known to live in Europe, the species Esox lucius or northern pike, which is also found in North America and Asia. Its taxonomy has remained unchanged since it was described by the zoologist Linnaeus in 1758. Dr Fontaneto, co-author of the research, said: “The discovery of a new species of a large and common fish in Europe is a rare surprise. Most new discoveries of fish species are of small, obscure and understudied fish that live only in geographically remote and inaccessible small lakes.”
Dr Fontaneto and his Italian colleagues from the University of Perugia have been studying the characteristic grey-green stripes and spots on the pikes’ scales. These broken patterns camouflage the fish against aquatic vegetation, hiding them from their underwater prey and from predators on the land.
They noted that all pike from northern lakes have a body pattern made up of round spots, whereas pike from the south have one of a variety of patterns, including star-shaped spots and vertical, horizontal or diagonal stripes. The researchers also counted how many scales run horizontally along the pikes’ lateral line, finding that southern pike have between 101 and 115 scales, compared with fish of the northern species, which have between 125 and 148 scales. They also sampled the animals’ DNA, and were able to identify several genetic differences between the two newly acknowledged species.
The researchers say that in order to maintain the integrity and population numbers of both newly defined species, Europe’s wildlife and fisheries managers should acknowledge these findings and review their practices and policies. The study was published in the journal PLoS One in December.
— Simon Levey, Communications and Development
Tags: Life Sciences
Posted in Research | Comments Off on New pike species doing too well in Italy
Comments are closed.
