Roach: What the Fisherman Should Know
The roach (Rutilus rutilus) is subject to considerable variety in colour and shape. The back is blue-black, blue-green, grey-green, grey-brown, or green, and the flanks are either predominantly silvery or bronzed. The silver-flanked fish is the more common, probably because all young fish are of this colour, the brassy colours developing in certain fish in maturity. The underside is cream, white, or buff. Within the limits described colour varies according to age, type, and locality.
The dorsal fin is darker to conform with the colours of the back. It is generally a red-brown colour, and sometimes red-streaked. The fins of the lower body are pink-tinted but may be grey, crimson, or yellow with red streaks. The tail fin is similar to the dorsal fin.
Body shape varies considerably in maturity, but young fish tend to be slim and spindle-shaped. Some fish retain this characteristic throughout their lives while others become decidedly hump-backed and deep-bellied. Yet others tend to become broad-backed and reminiscent of the CHUB. Three varieties of roach, resembling DACE, RUDD, and CHUB, were described by Schmidt in his Scandinavian Fishes (1892) and these conform roughly to the descriptions given here. Schmidt considered the differences to be largely due to heredity rather than to environment and gave each type a sub-title: Rutilus rutilus var. crassa, the chub-like roach; var. elata, the rudd-like roach; and var. elongata the dace-like roach. These distinctions are not today accepted by most zoologists, but most anglers will have found roach roughly corresponding to one or another of the types.
It is tempting to suggest that the slimmer varieties are found in fast waters while their plumper cousins belong in lakes and ponds, but this theory is far from being borne out by the facts. Deep-bellied, bronze-flanked fish are typical of the Hampshire Avon for instance, and are also frequently found in gravel pits and reservoirs. The slimmer fish so often found in lakes are also commonly to be found in the Fenland drain waters as well as in the Thames, Medway, Trent, and Great Ouse. In many waters, such as the Kennet, roach of two distinct types are to be found, the golden-flanked deep-bellied fish inhabiting the same reaches as the slim, silvery ones. Bronze-flanked fish are less often found in the Thames, where there are nevertheless plenty of deep-bodied fish. This suggests that Schmidt was quite correct in ascribing these differences to heredity and genetical structure rather than to environment.
With so much variety in food supplies from one water to another it is hardly surprising that researches into growth rates show apparently conflicting results. In optimum conditions, for example, such as those found in the Hampshire Avon and one or two other waters such as reservoirs, which occasionally produce large fish up to 1.5 kg (3 lb) or so, the growth rate is high. A two-year old fish might attain a size of 11-12 cm (445 ins), putting on a further 2.5 cm (1 in) each year and reaching the Thames anglers’ size limit 20 cm (8 ins) in five years. Such fish could reach the 1.5 kg (3 lb) mark at an age of about fourteen or fifteen, having achieved what is for a roach a fairly good old age. After this, growth falls off and the fish ‘go back’. At the other extreme, in waters where food supplies are limited by over-population or poor conditions, the fish may fail to attain 20 cm (8 ins) by the time it is nine or ten years old.
The great majority of roach waters lie somewhere between these extremes and average conditions can produce fish capable of 7.5-9 cm (3-34- ins) length by the end of the second year. These may become sizeable in six or seven years, which leaves them plenty of time to put on further weight before reaching advanced age and ‘going back’.
Average waters will contain a fairly good head of fish of about 450 g (1 lb) in weight. Some up to 900 g (2 lb) will probably also be present, but this weight will generally represent the peak of growth. 900 g (2 lb) fish are, of course, few and far between in comparison with the millions of 15 cm (6 in) naïve youngsters which the angler so often grumbles about. Losses due to predators and other natural causes naturally increase as age increases.
Roach occasionally interbreed with other allied species which happen to be spawning in close proximity to the roach shoals. Hybridism is accidental, and arises from fishes on the fringes of the shoals intermingling, eggs from one species being fertilized by milt from the other. Hybridism of this kind arises rarely between roach and BLEAK, commonly between roach and RUDD and between roach and.
The roach-bleak and roach-rudd hybrids are unlikely to give rise to problems, though they are difficult to identify. In the case of the-roach hybrid, the resultant mixture often reaches specimen proportions. This can inspire false claims for record or specimen fish.
The bream-roach cross is often referred to as a pomeranian bream, and was once thought to be a separate species. It is now recognized for the hybrid it actually is. It is intermediate in appearance between roach and bream and may resemble either parent predominantly, having a strongly forked tail and a slim body, and combining depth of body as found in bream with the roach’s thickness of body. This means that it may weigh upwards of 900 g (2 lb).
Such fish can be recognized instantly and quite definitely by counting the number of branched rays in the anal fin. The true roach bears only nine to twelve such rays, the bream between twenty-three and twenty-nine. The hybrid bears between fifteen and nineteen and is, therefore, clearly neither roach nor bream, and cannot easily be mistaken for another species.
It is impossible to define typical haunts of the roach with any accuracy because they inhabit waters of widely different kinds, their haunts being as variable as their structures and, in any event, changing according to the time of the year. Certain generalizations are possible, however. Other things being equal, roach tend to seek out hard bottoms, preferring gravelly, sandy, rocky, concrete, and sometimes even hard clay bottoms, to soft surfaces such as silt and mud.
Against this must be considered the fact that roach are very fond of weed, which provides cover from predators, and offers good feeding. Where there is plenty of weed on the bottom or reedy margins, the roach will seldom be found very far away —especially during the summer.
Very little is known with any certainty about the roach’s seasonal movements because little research had been undertaken. Most available evidence is the result of direct observation by generations of anglers who usually know where they catch their fish at various times of the year. The reasons for those movements which do occur are not hard to find.
During the months of April to June, earlier or later according to the severity or mildness of the year, the fish move into the weeds and reed margins, often in very shallow waters, and well up in the minor tributaries. In lakes and ponds the choice is restricted, but even here the fish tend to move out of the deeper waters, and make the best of available weed and shallows.
Spawning is communal, and no obvious selection of mates is observable except occasionally among older and larger fish where the shoals are themselves smaller and fewer. In this event
the spawning groups are smaller and, if space permits, big fish tend to separate from the smaller ones. The eggs are deposited on the weed stems and left to fend for themselves. By June the roach are seeking out the faster reaches to recover from the rigours of spawning. Now they occupy mill-tails, weir pools, and the swift streamy stickles, but they still prefer shallow waters.
About July the shoals tend to move out into the deeper runs, taking up residence in the typical gravelly scours and runs between the weed. They seem to prefer to remain in or by the `stream’, where their search for food is assisted by the hatching of myriads of eggs provided by various insects and crustaceans, so that they have a virtual conveyor belt continually bringing food along. With the onset of colder weather, however, the fish tend to spread more, moving away from weed and into deeper waters scattered about the whole river. By the time the weeds have rotted, the roach are fairly firmly established in the deeps, returning to the shallows only during warmer spells.
As the winter floods approach, the shoals are continually on the move, patrolling many miles in the course of the day in the never-ending search for food. When the floods arrive, the lay-bys, eddies and ox-bows provide temporary refuge from the worst of the fast water, and the shoals are not slow to follow the river up and over the banks on to the meadows and grassy fringes where some welcome extra rations are provided.
During periods of drought the fish instinctively avoid being left high and dry, receding with the water into the centre channels where it remains comparatively deep. They are now continually moving, hunting or being hunted until, when spring comes, the fresh weed growth and the breeding season bring welcome cover and a whole glut of extra food in the form of many creatures which live and breed amongst the weed. Here the fish remain until they themselves have spawned.
Throughout the year the general diet of the fish is subject to some modification. During the early season silkweed and the profusion of insects provide the basic food, but later in the year it is to the adult insects as well as to molluscs and crustaceans that the fish must look for food, though they still show a marked liking for silkweed. By autumn, food is scarcer and the fish must move about in search of freshwater shrimps, snails, leeches, bloodworms, and other food forms still available. Sometimes they are forced to exist on fat reserves remaining from the summer, and as they become leaner they become also beautifully conditioned. In still waters some fish fall into a state of semi-hibernation from which they only arouse themselves when the temperature rises considerably. During winter, still-water roach fishing is less attractive than river fishing for this reason.