Trout Flies of Devon and Cornwall, and When and How to Use Them

by G. W. Soltau

Mr. Shaw’s ingenious experiments, which have been continued with the greatest care and attention for a long period, disprove the correctness of this opinion. This gentleman constructed three ponds, the banks so raised, and otherwise formed in such a manner, that it was impossible for any fish to escape, or for any other fish to have access to them. On the 4th of January, 1837, some fresh spawn was deposited in one of these ponds, on the 28th of April, one hundred and fourteen days after impregnation, the young salmon were excluded from the egg. On the 24th of May, twenty-seven days after being hatched, the young fish had consumed the yolk which remains attached to the lower part of the body, and which serves them for nourishment; the characteristic bars of the parr had then become distinctly visible. From an unforeseen accident, his experiments upon this brood were abruptly terminated. With a second, however, he was more fortunate. On the 27th January, 1837, he deposited some spawn in one of his ponds; on the 21st March, the embryo fish were visible to the naked eye. From a minute inspection, he found that they had some appearance of animation, from a very minute streak of blood which appeared to traverse for a short distance the interior of the egg, originating near two small dark spots, not larger than the point of a pin. These two spots ultimately turned out to be the eyes of the embryo fish. On the 7th May, (one hundred and one days after impregnation) they had burst the envelope, and were found among the shingle in the stream; at this period the head is larger in proportion to the body, which is exceedingly small, and measures about five-eighths of an inch in length; of a pale blue or peach blossom colour. But the most singular part of the fish is the conical, bag like appearance, which adheres by its base to the abdomen. This bag is about two-eighths of an inch in length, of a beautiful transparent red, very much resembling a light red currant. The body also presents another singular appearance, namely, a fin or fringe, resembling that of the tail of the tadpole, which runs from the dorsal and anal fins to the termination of the tail, and is slightly indented. This little fish does not leave the gravel immediately after its exclusion from the egg, but remains for some time beneath it, with the bag attached, which contains its supply of nourishment.

On the 24th June, Mr. Shaw found the bag had disappeared, but the symmetry of the form was as yet but imperfect. At the end of two months, (7th July) the shape was much improved. At the age of four months (7th September) the characteristic marks of the parr or samlet were partly developed. Two months later (six months old 7th November) the average length was three inches. On the 10th May, 1838, the fish being then twelve months old, were improved in condition, and measured four inches: they had changed their winter coating for that which may be called their summer dress. On the approach of autumn, the whole of the salmonidæ, while resident in fresh water, acquire a dusky exterior, accompanied by a considerable increase of mucus or slime. As the summer advanced, they continued to increase in size; and on the 14th November, being then eighteen months old, they measured six inches in length, and had attained that stage, when all the external markings of the parr are strikingly developed. On the 20th May, 1839, the fish being then two years old, they measured six inches and a half long, and had assumed the migratory state.

This change commenced about the middle of the previous April; the caudal, pectoral, and dorsal fins assuming a dusky margin, while the whole of the fish exhibited symptoms of a silvery exterior, as well as an increased elegance of form.

The specimens in question, so recently a parr, exhibited a perfect example of the salmon fry, or smolt. Mr. Shaw having thus traced the spawn of the salmon up to this point, it will now be necessary to pursue our inquiries until we find the matured fish. The descent of these little fish takes place much about the same time in all rivers, commencing in March, and continuing through April, and part of May. They first keep in the slack water, by the side of the river; after a time, as they become stronger, they go more towards the mid-stream; and when the water is increased by rain, they move gradually down the river. On meeting the tide, they remain for two or three days, in that part where the water becomes a little brackish from the mixture of salt water, till they are inured to the change, when they go off to the sea all at once. There their growth is very rapid, and many return to the brackish water, increased in size, in proportion to the time they have been absent. Fry, which were marked in April and May, have been caught on their return at the end of June, weighing from two to three pounds in weight. These are sold in our markets as salmon peal, when of a larger size they are called gilse. A second visit to the sea gives these another increase, when they return to the rivers as salmon.

By the term “gilse,” is meant young salmon that have only been to the sea once. It seems worthy of remark, that salmon are sometimes smaller than gilse; but although such gilse have only been once at sea, yet the period they have remained there, must have exceeded the two short visits made by the small salmon, and hence their superiority of size.

It has been a constantly received opinion, that all the young fish, after their first visit to the sea, return to the rivers in which they had been bred; numbers of marked fish have certainly been retaken in their native rivers, but from the observations of Dr. Heysham, and Sir William Jardine, it is evident, that if the fish happen to have roved far from the estuary of their native rivers, they run at the proper season, up any stream, even the first they encounter, the temperature and condition of which are congenial to them.

The growth of salmon, from the state of salmon fry or smolt, to that of salmon peal and gilse, has been shown to be very rapid, and the increase of weight, during each subsequent year, is believed to be equal, if not to exceed the weight gained within the first. That this fish is a voracious feeder may be inferred from the degree of perfection in the arrangement of the teeth; yet few, of the many observers, who have examined the stomach, have been able to ascertain the exact nature of that food which must constitute its principal support.

Faber, in his “Natural History of the Fishes of Iceland,” remarks, “The common salmon feeds on small fishes and various small marine animals.” Dr. Fleming confirms this, when he states that their favorite food in the sea is the sand eel.

In a Prize Essay, published in the transactions of the Highland Society, Mr. Morrison says, “I have taken salmon within flood mark, some of which had two, and others three, full-sized herrings in their stomachs.”

Mr. George Dormer, of Stone Mills, in the parish of Bridport, put a female salmon which measured twenty inches in length, into a small well, which measured only five feet by two feet four inches, and there was only fifteen inches depth of water. In this confined place she remained twelve years, she would come to the top of the water and take meat off a plate, and would devour a quarter of a pound of lean meat in less time than a man could eat it. She would allow Mr. Dormer to take her out of the water, and when put into it again, would immediately take meat from his hands. Some time since, a little girl teased her by presenting the finger and then withdrawing it, till at last she leaped a considerable height above the water, and caught her by the said finger, which made it bleed profusely. At one time a duck approached the well, and put in its head to take a draught of the water, when Mrs. Fish, seeing a trespasser on her premises, seized the intruder by the bill, and a desperate struggle ensued, which at last ended in the release of Mr. Drake from the grasp of Mrs. Fish, and no sooner freed, than Mr. Drake flew off in the greatest consternation and affright; since which time to this day, he has not been seen to approach the well, and it is with great difficulty he can be brought within sight of it.