NATIONAL FISHERY CONGRESS. 
269 
darns and natural falls, for tlie latter form absolute barriers, whereas extensive 
fisheries merely limit the number of fish ascending to the extreme range of the river 
and not the length of that range; yet in many cases they atfect the future abundance 
of the species even more than the dams and natural falls. This is particularly 
noticeable in those narrow streams whose fluvial characteristics extend nearly or quite 
to the sea, as in most of the rivers between the St. Johns and the Neuse, and to some 
extent in the Susquehanna, the Hudson, the Connecticut, etc. In the Ogeechee, 
Savannah, Edisto, Pee Dee, and Cape Fear, the great bulk of the catch is obtained in 
the extreme lower end within 30 or 40 miles of the sea, and comparatively few shad 
ascend as far as the spawning- grounds. In the Connecticut nearly all the shad are 
caught within 20 miles of the mouth. The dams in those rivers perform a very unim- 
portant part in limiting the run of fish, for few shad ever reach those obstructions. 
In the broad estuaries tributary to the sounds of North Carolina and to the 
Chesapeake and Delaware bays the effect of netting is not so apparent, yet even in 
those waters only a small percentage of the shad ever reach the spawning-grounds. 
Formerly the great bulk of the yield was obtained from the middle and upper 
sections of the rivers, while at present nearly all the catch is obtained in the lower 
section and in the salt water of the estuaries. The extension of the fisheries into the 
estuaries is of recent origin, dating only from the middle of the present century, and 
their development has been principally during the past twenty years. It requires 
large and costly apparatus to prosecute the fisheries there, and forms suitable have 
come into use only quite recently. With the exception of drift nets in Delaware Bay, 
New York Bay, and one or two less important places, and the mackerel purse-seines, 
which take a few shad on the New England coast, pound nets and stake nets are the 
only forms of apparatus employed in catching shad in salt water. Over 90 per cent 
of the shad caught in the salt water of the Chesapeake region are taken in pound 
nets, yet the use of that apparatus there dates only from 1865, and not until 1875 
were they extensively employed. Stake nets and pound nets, which catch practically 
all the shad taken in the salt water of North Carolina, have been used in that region 
only since 1865. 
At present nearly one-half of the total shad yield on the Atlantic seaboard is 
obtained in salt water, and those fisheries are becoming more extensive each year. 
Table B, on page 271, shows that in 1896, 6,252,464 shad, over 47 per cent of the total 
yield, were caught in regions which half a century ago yielded none whatever; this in 
some measure compensating for the 4,000 miles of river-course from which they are 
now wholly excluded and the lengths from which the exclusion is partial. It thus 
appears that the principal change in the fisheries during the past fifty years has been 
one of location rather than extent of the total yield, the great increase in the estuaries 
compensating for the decrease in the headwaters. This change in the fishing-grounds 
results in a large portion of the fish being taken before they reach the spawning areas 
in fresh water, thereby preventing them from adding their quota to future supply 
almost as effectually as though they were excluded therefrom by means of dams or 
otherwise. But the same result is accomplished when the fish are caught after they 
have reached those areas and before they have spawned. Furthermore, moving the 
seines and other apparatus of capture over the spawning-grounds disturbs and drives 
away the fish from those areas, and also destroys many of the eggs and young shad 
already there. 
