The Zander is not a native to the British Isles, it originally came from Eastern Europe but is now widespread throughout Germany, Holland and France. In 1878 the Ninth Duke of Bedford introduced 23 Zander into the lakes of Woburn Abbey. They remained localised until 1963 - when 97 were released into the Great Ouse Relief Channel in Norfolk. Since then they have spread slowly across England.
It goes without saying the the Zander, a shoaling fish, is highly adaptable. It thrives in large, slow-flowing fen drains and rivers. But it does not seem to do well in fast-flowing, clear rivers or in shallow waters where the oxygen content is low. Coloured waters and even tidal river stretches (where the salinity is high) produce good Zander. In still waters you can find them during the day in deep water or near drop-offs hiding from the intense light.
What makes the Zander exceptionally efficient hunter is that they sometimes gather in a pack to feed on small fish (usually at dawn, dusk and during the night). The Zander chase after the fish, grabbing them from behind and swallowing them.
Because other species cannot see as well as the Zander in murky water or at night, they have a distinct advantage. They also feed on worms and leeches as well as small fish such as Roach.
Zander usually spawn between April and June. A group gathers over stones or a gravel bed and the mature females dig a hollow in the gravel, lay about one to two million eggs and then guard them until they hatch.
After hatching, the larvae live off their yolk sacs, reaching about 1/4in (6mm) long after one week. When the yolk sac is used up, the young eat plankton and insect larvae. Zander begin feeding on other fish at the age of three months - or when they are about 4in(10cm).
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