Perch
Perca fluviatilis
The usual size when they are adults is 25 to 40 cm The mouth has small teeth, and unlike sandra she has no canine teeth. The body is greenish with 5-7 transverse black bands. It has two separate dorsal fins, the first with bony radii. The anal fins, caudal and pelvic are reddish in adults.
The perch is native to central and northern Europe. It was introduced to Catalonia in 1980 to the Muga basin, and since then has expanded its distribution. It is currently also present in Lake Banyoles, and in the rivers Ebro and Segre.
Prefers stagnant or slow flowing waters, with aquatic vegetation. It reproduces in spring. Females lay eggs in aquatic vegetation or submerged branches. It is a predatory species, which feeds on invertebrates and fish fry. For this reason it poses a threat to native species.
Distribution
Pike perch
Sander lucioperca
Large fish, up to 1 m in length. It has a large mouth with numerous teeth, among which some very developed canines stand out. It has two dorsal fins, the former with spiny radii. The body is gray-green, silver to the flanks, with dark vertical bands
Pike perch is native to most of central and northern Europe, It was introduced to Catalonia during the decade of 1980, and has expanded remarkably through illegal introductions to virtually every basin.
It lives mainly in reservoirs, but it can also be found on some stretches of larger rivers. It adapts very well to murky waters thanks to its good vision. It has a mainly nocturnal and twilight behavior, as they tend to avoid bright light. They feed on invertebrates when they are young, and of fish in adulthood.
In some reservoirs it is found in fairly high densities and can cause strong pressure on native ichthyofauna due to its predatory behavior..
Distribution
