Although they are not as prolific or widespread as common bream, there are plenty of silver bream in the slow-flowing waters of eastern England.
Only when young do the two species have the same silver colouring. The common turns golden olive with age, but the silver (or white) bream does not change colour at all so confusion between an immature common bream and a mature silver is quite likely.
The silver grows to only half the size (average 15-18cm/6-7in) of the common (average 30-45cm/12-16in, though some grow much bigger). In addition the silver has bigger and fewer scales and a larger eye than the common and its pectoral and pelvic fins are reddish – not dark like those of the common bream.
A sure way to tell them apart is to count the number ofscales along the lateral line -the true silver bream has 44-48, the common bream 51-60.
The two species, along with roach and rudd, interbreed freely. The hybrid fish’s colour, number of scales and so on are intermediate between those of its parents. It may take an expert to distinguish between a hybrid and a true silver bream.
Like the common, the silver bream has a deep, plate-shaped (laterally flattened) body, enabling it to swim easily between the closely spaced stems of weeds. This increases the number offeeding grounds for the fish as well as providing shelter from predators – bream are the staple diet of pike in many waters.
The silver bream occurs in much the same habitats as the common – lowland lakes, canals, slow-flowing rivers and drains. You’ll find it in waters which are heavily coloured with algae or suspended solids.
Most active in summer and autumn, bream in still waters tend to become lethar- gic during the winter. They live in huge shoals and, as the members of the shoal grow older and bigger, so the numbers decrease. You can sometimes find them in mixed shoals with dace, rudd and roach.
Feeding on both the bottom and in mid-water, the silver bream eats small animals • snails, worms, crustaceans, insect larvae and so on – and plants. Shoals, which can contain dozens of fish, cruise along the bot tom in search of food — because there are so many of them they have to move continu ally to find enough for them all.
Large shoals of fish stir up a great deal of mud when rooting around for food. Gases are released which quickly carry the mud to the surface, even in deep areas – so anglers should look out for bubbles and discoloured water when trying to locate a shoal. These mud swirls are especially apparent in still waters.
Silver bream spawn between May and July • weed beds in sunny shallows are their favoured spots. Before spawning the males develop hard, bony tubercles on head and body, and they mark out and guard terri tory for up to a week before the females arrive on the scene.
Spawning occurs at dawn or dusk – the males drive the females into the weeds and then chase them around. The friction caused by the males rubbing their bodies against the females draws the eggs out and the males then fertilize them with milt. Being sticky, most of the light yellow eggs adhere to the weed, but those that fall to the bottom die from lack of oxygen.
Once the eggs have hatched, growth is moderate and after one year most fish have reached 6-8cm (2-3in) long. At this stage they are fairly slender and do not develop the plate shape until they are a couple of years old.