CRAYFISH AND TROUT
About the middle of August, when walking by one of the locks on a disused canal in the Ock Valley, I saw a man engaged in a very artistic mode of catching crayfish. The lock was very old, and the brickwork above water covered with pennywort and crane's-bill growing where the mortar had rotted at the joints. In these same joints below water the crayfish had made holes or homes of some sort, and were sitting at the doors with their claws and feelers just outside, waiting, like Mr. Micawber, for something to turn up. To meet their views the crayfish catcher had cut a long willow withe. From the tapering tip of this he had cut the wood, leaving the bark, which had been carefully slit and the woody tip extracted from it. This pendant of bark he had made into a running noose, and leaning over the bank he worked it over the crayfish's claws and then snared them. It was a neat adaptation of local means to an end; for if you think of it, string would not have answered, because it would not remain rigid, and wire would be too stiff for the job.
Crayfish catching, until lately one of the minor fisheries of the Thames, is now a vanished industry. Ten years ago the banks of the river from Staines to the upper waters at Cricklade were honeycombed with crayfish holes, like sandmartins' nests in a railway cutting. These holes were generally not more than eighteen inches below the normal water line of the river. In winter when the stream was full fresh holes were dug higher up the bank. In summer when the water fell these were deserted. The result was that there were many times more holes than crayfish, and that for hundreds of miles along the Thames and its tributaries these burrows made a perforated border of about three feet deep. The almost complete destruction of the crayfish was due to a disease, which first appeared near Staines, and worked its way up the Thames, with as much method as enteric fever worked its way down the Nile in the Egyptian Campaign after Omdurman. The epidemic is well known in France, where a larger kind of crayfish is reared artificially in ponds, and serves as the material for bisque d'ecrevisses, and as the most elegant scarlet garnish for cold and hot dishes of fish in Paris restaurants; but it was new to recent experience of the Thames. Perhaps that is why its effects were so disastrous. The neat little fresh-water lobsters turned almost as red as if they had been boiled, crawled out of their holes, and died. Under some of the most closely perforated banks they lay like a red fringe along the riverside under the water. Near Oxford, and up the Cherwell, Windrush, and other streams they were, before the pestilence, so numerous that making crayfish pots was as much a local industry as making eel-pots, the smaller withes, not much larger than a thick straw, being used for this purpose. Most cottages near the river had one or two of these pots, which were baited on summer nights and laid in the bottom of the stream near the crayfish holes. It must be supposed that they only use them by day, and come out by night, just as lobsters do, to roam about and seek food on a larger scale than that which they seize as it floats past their holes by day. That time of more or less enforced idleness the crayfish used to spend in looking out of their holes with their claws hanging just over the edge ready to seize and haul in anything nice that floated by. Their appetite by night was such that no form of animal food came amiss to them. The "pots" were baited with most unpleasant dainties, but nasty as these were they were not so unsavoury as the food which the crayfish found for themselves and thoroughly enjoyed, such as dead water-rats and dead fish, worms, snails, and larvae. They were always hungry, and one of the simplest ways of catching them was to push into their holes a gloved finger, which the creature always seized with its claw and tried to drag further in. The crayfish, who, like the lobster, looked on it as a point of honour never to let go, was then jerked out into a basket. They rather liked the neighbourhood of towns and villages because plenty of dirty refuse was thrown into the water. In the canalised stream which runs into Oxford city itself there were numbers, which not only burrowed in the bank, but made homes in all the chinks of stone and brick river walls, and sides of locks, and in the wood of the weiring, where they sat ensconced as snugly as crickets round a brick farmhouse kitchen fireplace. They were regularly caught by the families of the riverine population of boatmen, bargees, and waterside labourers, and sold in the Oxford market. A dish of crayfish, as scarlet as coral, was not unfrequently seen at a College luncheon. Possibly the recovery from the epidemic may be rapid, and the small boys of Medley and Mill Street may earn their sixpence a dozen as delightfully as they used to. Young crayfish, when hatched from the egg, are almost exactly like their parents. The female nurses and protects them, carrying them attached to its underside in clinging crowds. They grow very fast, and this makes it necessary for the youthful crayfish to "moult" or shed their shells eight times in their first twelvemonth of life, as the shell is rigid and does not grow with the body. The constant secretion of the lime necessary to make these shells is so exhausting to the youthful crayfish that only a small number ever grow up. In America, where a large freshwater crayfish nearly a foot long is found, its burrowing habits are a serious nuisance, especially in the dykes of the Mississippi. In those streams from which these interesting little creatures have entirely disappeared it might be worth while to introduce the large Continental crayfish. As it is bred artificially, there would be no difficulty in obtaining a supply, and it would be a useful substitute for the small native kind.