When the fry are three or four months old, they are "planted." After being freed they work their way gradually down to salt-water, which pushes up into the lagoon, and finally out into the bay. They return frequently to fresh water and for at least a year work in and out with the tides.
The majority of fry cling to the fresh-water vicinity for two years after hatching, at which time they are about eight inches long. The second spring after hatching they sprout out suddenly in bright and glistening scales, which conceal the dark markings along their sides which are known as parr-marks. They are then called "smolt," and are as adult salmon in all respects save size.
In all rivers smolts pass down to the sea between March and June, weighing only a few ounces. The same fall they return as "grilse," weighing from three to five pounds.
After their first spawning, they return during the winter to the sea; and in the following year reascend the river as adult salmon. Males mature sexually earlier than females.
The time of year when salmon ascend from the sea varies greatly in different rivers, and salmon rivers are denominated as "early" or "late."
The hatchery at Karluk is a model one, and is highly commended by government experts. It was established in the spring of 1896, and stripping was done in August of the same year. The cost of the present plant has been about forty thousand dollars, and its annual expenditure for maintenance, labor, and improvements, from ten to twenty thousand. There is a superintendent and a permanent force of six or eight men, including a cook, with additional help from the canneries when it is required.
There are many buildings connected with the hatchery, and all are kept in perfect order. The first season, it is estimated that two millions of salmon-fry were liberated, with a gradual increase until the present time, when forty millions are turned out in a single season.
The superintendent was taken completely by surprise by our visit, but received us very hospitably and conducted us through all departments with courteous explanations. The shining, white cleanliness and order everywhere manifest would make a German housewife green of envy.
At this point Karluk River widens into a lagoon, in which the corrals are wired and netted off somewhat after the fashion of fish-traps, covering an area of about three acres.
Fish for the hatcheries are called "stock-fish." They are secured by seiners in the lagoon opposite the hatcheries, and are then transferred to the corrals. As soon as a salmon has the appearance of ripening, it is removed by the use of seines to the ripening-ponds.