Greedy chub Leucisus cephalus

In many ways chub look like dace at first glance. Both have black tails and Grey or green backs. Chub, however, usually have brassy coloured flanks, orange anal fins and big mouths, and they grow much larger than dace. But when in doubt, look at the fish's fins. Chub dorsal and especially anal fins are convex (curved outward) while those of dace are slightly concave (curved inward).

Small chub of 7.5cm (Sin) or so eat large invertebrates, worms and the fry offish. Chub are omnivorous; that is, they eat fish, insects and vegetable matter (such as silkweed, berries and bread). In fact, if an elderberry tree is overhanging a river bank, for example, chub often gorge themselves with ripe berries.

Fish of over 1.4kg (3lb) may eat small bullheads, minnows, roach and dace. They don't have teeth in their mouth; their mighty pharyngeal teeth, located at the base of the throat, can crush just about any food item. This includes crayfish which, despite their hard shell, are quickly demolished.

Running water is the best place to look for chub - especially in any steady-flowing lowland or middle reach of river. They don't thrive in upland waters, which are more suited to trout, salmon and grayling. Chub are a retiring fish, and they rely much on the shelter of overhanging trees, rafts of debris, underwater weeds and undercut banks -cover is an essential part of their habitat.

During the afternoon, however, chub often sun themselves. You can see them on clear, windless summer days, but be careful when approaching them, for they spook easily. They may also spook if you try to cast directly above them. Casting a yard or so upstream and in front of the fish often does the trick.

Because chub are adaptable, they can also survive in still waters; it's here where they grow fat as barrels. Crystal-clear gravel pits contain many large specimens. On shallow gravel bars between 30-90cm (1-3ft) deep you can often see them basking in the sun.

Chub usually spawn between April and June, depending on the temperature of the water. The adult's swim upstream to shallow gravelly runs and breed only in flowing water.

Each female can shed up to 100,000 eggs over gravel, weeds or debris on the riverbed. After eight to ten days the fertilized eggs hatch. The fry feed in shoals on microscopic organisms (plankton).

As they grow, they remain in shoals. Even the mature fish group together. Only the very large fish become solitary.

Hardwick Gravel Pit, Oxfordshire Some huge chub, perhaps over 3.6kg (8lb).

River Stour, Dorset A famous chub river with many 1.8-3.2kg (4-7lb) fish.

River Avon, Hampshire Superb chub fishing with fish up to at least 2.7kg (6lb).

Chesterfield Canal, Retford, Nottinghamshire Matchwater with 1.4kg (3lb) fish.

River Trent The tidal reaches of the river Trent are home to many big chub of up to 3.2kg (7lb).

Manor Farm Fishery, South Muskham, Nottinghamshire Many 1.8-2.3kg(4-5lb) chub.

River Derwent, Borrowash, Derbyshire An excellent water with big stocks of chub, the matchman's dream.

Along with big barbel and roach, the Wensum upstream of Norwich offers good chub fishing.

River Derwent, Yorkshire Many 1.8-2.3kg (4-5lb) chub.

Weight: in Britain up to 3.6-4.1kg (8-9lb); average 0.9-1.4kg (2-3lb)

Length: up to 56-59cm (22-23in)

Life-span: 10-12 years

Favorite waters: steady-flowing lowland rivers and the middle reaches of rivers

• Chub can be distinguished from the dace by their convex dorsal and anal fins.

• They have large mouths for their size and their fins are rounded. The flanks are brassy and the anal and pelvic fins are orange.

• Chub will rise from the shelter of weeds to eat insects on the surface of the water.

The record British fish weighed 3.743kg (8lb 4oz) and was caught by G. F. Smith on the Royalty Fishery, River Avon, Hampshire in 1913. The fish was deleted from the record list, but now it has been reinstated after members of the National Association of Specialist Anglers located the cased fish and the facts behind its capture.

Chub patrol along the edge of an island or bask in the sunshine on shallow gravel bars. A heavily overgrown feeder stream is also a good place to locate resting chub.

An undercut bank may hold many good-sized fish. Chub face upstream just outside the main current to save energy.

Debris caught under overhanging trees or bushes makes a raft, providing shelter for chub. A raft of debris caught in a fence would also be another shelter spot.

Drinking cattle often stir up insects and debris. Once the cattle leave, chub sometimes

come to feed and sun themselves in the shallow water.

Slack water at the edge of a weirpool may hold large specimens on the lockout for large gatherings of fry.