Data sheet zander
Latin name:
Sander lucioperca
Trade name:
walleye
order name:
perch
Family:
Real perch
Genus:
sanders
Origin:
Asia, Russia, Europe
Size (in cm:
up to 130
pond size
Length and width:
at least 4 m depth
water values
Temperature:
about 15 °C
behavior/stocking
Area:
In deep water in darker places
Lining:
fish
Behave:
hunts fish at dusk and in murky waters
Number:
several juveniles, older animals tend to be loners
Life expectancy:
about 20 years
socialization:
in aquaculture
Difficulty level:
easy Tiia Monto, Rousse Ecomuseum – Sander lucioperca, CC BY-SA 4.0
Key data on the zander
The zander is a predatory fish that lives in fresh water but also in brackish water. This predator hunts mainly at night or at dusk. His good eyesight and hearing help him with this. During the day and on cloudy days it is mainly active in turbid water.
At night it prefers to stay in water depths between 4 and 6 m, but during the day it prefers even deeper zones. Measured by its body size, the pike-perch is the largest species of perch living in the freshwaters of Europe.
Small fish fear this predatory fish. It occurs in many European regions, America, Russia and Asia. His favorite bottom is hard, with murky water. The juvenile zander often swarm in groups, but older and larger zander prefer to be solitary in deep water.
appearance
The pikeperch has scales and a crest, showing different shades of colour. The body is green, grey-brown or beige, while the abdomen is silvery white. The two partially transparent dorsal fins complete the beauty of the fish.
Its pointed head has a large and deep mouth with irregularly arranged and very sharp fangs and canine teeth. The fish has a large symmetrical caudal fin.
gender differences
With zander, it is not so easy to distinguish between male and female fish. Males have a narrower and darker back. Females have a higher back in front of their dorsal fin.
reproduction
In the spring, the zander breeds. Of course, the water temperature plays a role. Between 12 and 15 °C is optimal. Males are sexually mature at 2 to 4 years of age. For females it is 3 to 5 years.
Zander love shallow pits for spawning close to the shore with hard ground. The average water depth here is between 1 and 3 m, which is otherwise unusual for zander. The zander first cleans its spawning pit thoroughly with its tail fin.
The spawning
The female zander lays up to 200,000 zander eggs for every kilogram of its body weight. This attaches it to stones or plants with the help of an adhesive substance. There they are fertilized.
The male guards the spawning pit and makes sure that no mud is formed or that no spawn predators come near the eggs. The zander larvae hatch after 7 days and grow to around 5 mm.
They do not require any food after hatching as they first eat the yolk sac. After that, they begin to consume plankton on their own. When the juvenile zander have reached a sufficient size, they hunt other species of fish. In autumn, the young animals are between 5 and 10 cm in size.
Artificial occupation of water bodies
In the meantime, the zander has been able to multiply considerably in the stock through artificial stocking. Environmentalists and scientists are critical of the artificial stocking of bodies of water where it does not occur naturally, because the zander is a predatory fish and could decimate important fish species.
He now lives, for example, in the Elbe, the Danube, the Weser, the Moselle or in the Rhine. There are even zanders in Turkey or on the Caspian Sea.
Within Eastern Europe, the pike-perch stocks have been greatly reduced, so that this fish species is bred as food fish in so-called aquacultures. They are considered harmless to the ecosystem, but many breeders feed them wild fish.
rearing and socialization
breeding in aquaculture
The zander is one of the best-known Central European freshwater fish and is a popular food and sport fish. He is the hope for Central European aquaculture.
Zander have only recently been cultivated in aquaculture. About 58 tons are produced annually in Germany, which is relatively low. Zander reach a high selling price and are characterized by their group living as suitable fish for aquaculture.
Breeding in pond systems
Breeding zanders in ponds has so far hardly been the norm. This fish is partly a byproduct of traditional pond farming. The fish do not feel comfortable for long in rather shallow and muddy ponds. Zander love deep, sufficiently large waters and need hard ground to spawn. Juvenile fish are often placed in angling waters.
Zander breed in ponds on the bottom. They are provided with artificial spawning aids, such as coconut mats or small plants. The fish breed in the pond during the spring, which is their nature.