From pp. 228-230.
No objective studies have been made to date concerning the actual effects of the introduction of artificially-propagated fry upon the natural populations of shad. It is signifcant that the rash of hatcheries that broke out decades past was roughly contemporaneous with the highest production figures available on the annual shad harvests. Paradoxically, as shad have declined in numbers over the years, a reduction in the number of shad hatcheries occurred, so that today only one major shad hatchery remains. The principal justification for the expenditure of large sums of money and personnel on shad hatcheries was the supposedly rehabilitating effect upon the total fisheries.
Stevenson (1896) stated that "The history of the shad fisheries shows that there was a decrease in the yield in nearly every river on the coast until 1880, when the results of artificial propagation became apparent, not only maintaining an equilibrium, but increasing the abundance. Since 1880 the aggregate yield has greatly increased. It should be noted, however, that this largely-increased yield has been accompanied and even surpassed by an increase in quantity and effectiveness of the appratus of capture, but it was possible by the results of artificial propagation. Comparing 1880 with 1896, it is observed that the increase in the yield numbered 7,905,154. At 25 cents each, the average price paid by consumers, this represents an increase of $1,976,228 in value, over 60 times the expenditure for shad propagation, a result probably unsurpassed in any other line of fish-culture."
Stevenson's statement during the time of his survey seemed almost convincing proof that hatcheries were the answer to the perplexing problem of shad decline. On the other hand, the advocates of hatcheries did not continue their activity as the production of shad leveled off. Biologists noted that shad fry when planted in various bodies of water possessing fluctuation temperatures, chemical and other physical variations, foreign wastes, and many predators, probably did not have a good chance for survival. The difficulty of measuring survival and the ultimate disposition of the young shad only made the problem more complex. The lack of cleancut answers to the problem of the fate of young shad is one of the reasons that shad hatcheries continued to be supported by fishery authorities. A more important reason is political in nature. Fishermen have in the past manifested great faith in hatcheries, and to them it is the ultimate answer for replenishing of shad population. Some fishery authorities now regard shad hatcheries as a "token" measure toward appeasing criticism form fishermen who may otherwise object to the use of public funds in fishery work.
In recent years no competent fishery biologist has advocated the stocking of shad fry as a successful rehabilatory measure. Many states acting on recommendations of biologists have discontinued hatchery work; others have contined because of lack of information or because fishermen, many of whom have blind faith in artificial propagation, have demanded stocking. Nesbit (1939), in a discussion entitled, "Can more hatcheries solve the problem?" outlined in great detail the value and waste associated with hatcheries. Summarized, his arguments are as follows: (1) the stocking of hatchery reared shad fry will not replace the loss of shad from excessive fishing, as some fishermen have suggested, because of the progressive lowering of the brood stock level; (2) it is impracticable to provide hatcheries on a scale large enough to replace natural reproduction, i.e., almost four billion fry would be the annual minimum requirement needed in Chesapeake Bay alone; (3) although hatchery operation on the present scale is inadequate, efforst can be made to salvage shad eggs which would otherwise be wasted since it would involve little extra expense.
In cases where stocking records for shad fry and fingerlings are available, they have been compared to the commercial production of adults. In almost every case on significant correlation between them is evident. This has been particularly ture with records from Florida, North Carolina, Virginia, Maryland, Pennsylvania, New Jersey, and Connecticut. Information has been presented concerning these points in the discussion of the shad fisheries of each state. Moss (1950A) has presented one of the best recent discussions on hatcheries (See discussion in section on fisheries of Connecticut). His important ideas were as follows: (1) There are no real technical or financial obstacles to constructing or rebuilding shad hatcheries, hence fishery authorities have no practical reasons for blocking artificial propagations. (2) The reasons for doubting the value of shad hatcheries are found (a) in the mathematics of shad reproduction in which a shad in a hatchery contributes one-third of its roe but the remaining two-thirds and the fish are destroyed, while, if the fish were left in the river to spawn naturally, it would have about a 50 percent chance of escaping the nets and returning to spawn the following year, and (b) there appears to be no good correlation between the numbers of shad fry propagated in the period 1890-1938 and the catch of shad in Connecticut. (3) The hatchery effort, even in peak years, is of small magnitude when compared to natural reproduction in rivers. (4) It is believed that it takes about 100,000 eggs deposited in the river to produce one adult shad for market during average years of natural reproduction. (5) There is reason to believe that more fry are hatched, and survival is higher, under natural conditions than under artificial conditions. (6) It was concluded that the most promising rehabilitory measures are proper conservation and improvement of spawning habitat.
1. Hatcheries for the artificial propagation of shad were once considered the principal means for augmenting shad production during the years of decline. For over 100 years, form 1848 until 1952, shad hatcheries were operated in most of the states producing shad, but the greatest activity in this field occurred between 1867 and 1938.
2. There is no objective information on the survival and ultimate fate of stocked shad fry in rivers and streams and their relationship to shad runs that follow three or four years later.
3. There does not appear to be a correlation between the stocking of shad fry and the commercial production of adult shad, i.e., the stocking of shad has not perceptibly increased shad runs in rivers in which the fish were stocked as is believed by some fishermen and hatchery proponents.
4. The hatchery effort, even in peak years, is of small magnitude when compared to the natural reproduction in rivers.
5. The only justifications for shad hatcheries at this time appear to be (1) to salvage eggs that would otherwise be wasted and questionably, (2) to continue hatchery work as a "token" measure to appease fishermen who strongly believe in stocking methods in spite of evidience to the contrary. There are no real technical or financial obstacles to constructing or rebuilding shad hatcheries so that they may be continued as experimental projects or otherwise.
Moss, D.D. 1950A. The Connecticut River shad. Mimeo report, 1-6. Conn. State Brd. Fish and Game, Hartford.
Nesbit, R.A. 1939. How shad can be brought back in Chesapeake Bay and North Carolina. Mimeo. rept., U.S. Bur. Fish., (84052) : 1-7. [also presented before Tri-State meeting of conservation officers of Maryland, Virginia, and North Carolina, at Richmond, Dec. 7.] [reprinted in Md. Conserv., 17(1):12-24].