At various points in the Columbia and other rivers of the state, large sweep nets manipulated by hand are capable of being operated. The nets are let down and drawn up in the same spot, taking whatever fish may have swam within the diameter of it. This is of course fishing on a small scale.
The last compartment is usually also provided with a floor of netting which prevents the escape of all fishes finding their way into it. The salmon are then lifted out of the trap by means of nets or by a brail, which is a large net sometimes worked by hand or sometimes by a small engine.
This slide represents a catch of salmon on the floor of the cannery. In the larger and more modern plants very specialized machinery is used. The first machine through which the salmon are run is the "iron chink". This removes the head and the fins and opens and cleans the fish. The work is done very rapidly and quite completely. The cleaning, however, must usually be completed by hand, which process removes clotted blood and other waste material.
This is a typical scene showing a group of fishermen near the mouth of the Columbia. The salmon fishing season is comparatively short and the efforts of the fisherman are exceedingly strenuous during this period. In the Columbia river the spring season for salmon opens May 1st. The principal run of the Chinook and Sockeye salmon is in the spring and summer. Other species run best in the fall, so that the season for the Silver Salmon in the smaller rivers of the state is in the autumn. The salmon when taken by net, trap or wheel, are usually transported to the cannery by boat.
Comparing the work of the machine and the work done by hand. On the left side of the slide is shown hand work, and on the right side is the work of the machine. The machines does better work. After being completely cleaned, the fish are transferred to the cutting machine, which cuts the fish into pieces of proper size for canning. The knives may be regulated so that blocks may be cut of different sizes for one-pound of two pound cans. The next process is illustrated by the slide.
This slide represents a boat filled with salmon on its way toward the cannery. Many canneries are operated along the Columbia River and at points on the larger bays of the state. On reaching the cannery the fish are transferred to the floor of the cannery, as illustrated by the slide.
The output of our state hatcheries averages about 25,000,000 fry annually. Not only salmon, but trout and other food fishes are hatched and released into the streams. Salmon eggs and sperm are obtained from the adult fishes after they have ascended the smaller streams and the reproductive products are matured. Racks are constructed across the small streams and aginst these the fish crowd in the attempt to get by them. Here the fishes may easily be caught and the "stripping" process is carried out. By "stripping" is meant the extraction of the eggs and milt, or sperm, from the adults. The adult fishes are caught and by pressure of the hands the ripe eggs are forced from the female and the milt, or sperm, from the male. These products are then mixed in a container and fertilization soon occurs. Once fertilized, the eggs are placed in long, narrow troughs in the hatcheries. There are often wire bottomed trays to hold the eggs in the troughs. Water at low temperature is admitted at one end of the trough, circulates continuously over the eggs and escapes at the other end. The period of hatching requires from 35 to 70 days, different species requiring a different period of incubation. Conditions of environment will also alter this period. The care of the young after hatching under these artificial conditions is very important. Experimental work has been and is still being conducted to determine the best conditions under which the young will grow and thrive. The salmon when hatched have a yolk sack which they draw upon for food until it is completely absorbed, after which time they must be fed. It has been found that liver is one of the best foods for young salmon and cooked liver will cause them to increase in size and weight much faster than raw liver. It must be thoroughly powdered so that the small fishes can take it readily. Dried salmon or a mush are also used as food for the young fry. Milk curd has been found to be very good food. Lamprey Eels ground up and powdered are also used to some extent as food for young salmon. In previous years it was the custom to release the young from the hatcheries soon after the absorption of the yolk sack. At this period a very large percentage of them must have been destroyed by enemies long before they reached the sea. It has been found that the young fry have a much better chance of surviving if held in the hatcheries or in the ponds connected with them until the reach the length of four or five inches. This means holding and feeding them for a year or two after hatching. It makes it much more expensive, but insures a larger degree of success.
This shows the packing process going on in the warehouse. A standard case of salmon consists of forty-eight one-pound cans. Everyone recognizes that the best fishing grounds may be depleted of fish after a period of time if they are not restocked. With the enormous consumption of salmon increasing each year it is easy to see that the salmon supply would in a few years become exhausted if it were not replenished either by natural or artificial propagation. It is well known that some other species of food fishes are becoming greatly reduced in numbers by constant fishing. In these cases natural propagation does not supply enough young, or not enough reach maturity to restore the species. Our government, both federal and state, has for a long time recognized the necessity of artificial propagation in assisting nature to replenish exhausted streams and lakes with fish. The federal government through the United States Bureau of Fisheries has established more than thirty hatcheries in different parts of the country and annually several billions of fishes are handled. Hatching and transplanting are carried on almost coninuously, stocking new waters or maintaining the supply by planting in streams already provided. Our own state has twelve fish stations and hatcheries. The hatchery at Bonneville is known as the Central Station, and is the largest and best equipped.