Dip! dip! dip it is all day long, and as the little alewives are tumbled into barrels and carts, the eye of the practiced observer notes the plump sides and the brilliant iridescent coloring of the silvery scales, which indicate that the fish are loaded with a precious burden of eggs, to deposit which in the pond at the head of the stream is the motive which leads them to press forward so blindly into the trap men have set for them. In these enlightened days the town laws generally require that the brooks shall be unobstructed for one or two days each week, and so a few fish get by the barriers and are allowed to perpetuate their kind. In the past, however, many excellent “herring brooks” have been completely deprived of their fish. This illustrates how completely man has the destinies of river fish under his control. Suppose that instead of a fish house with movable barriers, an impassable dam had been built. Of course the fish would have been locked out, and their kind exterminated in that immediate region. This is precisely what has happened in almost every river and stream on the Atlantic coast of the United States. Shad and salmon were formerly abundant in every river of New England—and shad and alewives in every considerable stream south to Florida. Now, they are excluded, either entirely or in great part from the waters in which they once swarmed in great schools. Take, for instance, the Connecticut River. In colonial days, salmon were there in immense numbers. All summer long they were swimming up from the sea to the headwaters of the river, to Massachusetts, New Hampshire, and Vermont, where they deposited their eggs in the cool, clear rapids of the main river and its tributaries. They were so abundant that the shad fishermen used to require their customers to take one salmon with every shad, and, as the hackneyed old story goes, the apprentices were accustomed to stipulate in their papers that they should not be required to eat salmon above three times a week. In 1798 a dam was built across the river at Miller’s Falls. Next year many salmon were seen at the base of the dam, the following year a smaller number, and in less than ten years salmon had entirely disappeared from the Connecticut. Not a salmon was seen in those waters until seventy years later, when, in 1871, a single artificially bred fish was caught at Saybrook. I could show you a map prepared by an associate of mine, in which the present and former limits of the shad are shown, and you would see how they once ranged clear up into the mountains, far up the Susquehanna into New York State, up the Connecticut into New Hampshire and Vermont, and how now, in many rivers, they are confined to very restrictive stretches at the river mouths.