# Popular Science Monthly/Volume 73/October 1908/The Passing of the Sturgeon: A Case of the Unparalleled Extermination of a Species

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* THE PASSING OF THE STURGEON: A CASE OF THE UNPARALLELED EXTERMINATION OF A SPECIES
By WALTER SHELDON TOWER, Ph.D.
ASSISTANT PROFESSOR OF GEOGRAPHY, UNIVERSITY OF PENNSYLVANIA
THERE is little chance for doubt that the sturgeon was originally present in great abundance both in the coastal and the inland waters of the United States, since frequent mention of the species is found in the annals of the colonial period. Probably the earliest mention of this fish is found in Burk's "History of Virginia" where it is stated that a sturgeon fishery existed in that colony in 1626. For some reason, however, this early experiment did not prove successful and was abandoned. A century later Beverley's history of the same colony states that the rivers contained "multitudes of shad, rock and sturgeon," the last-named species being caught with nooses by the Indians. In fact, so abundant were the sturgeon that they often leaped into the canoes of the Indians, "as many of them do still (1722) every year into the boats of the English." A letter from William Penn to the Free Society of Traders in 1683 names sturgeon first in the list of abundant fish in the waters of his province. Throughout the region bordering on Delaware River and Bay the early settlers were struck at the immense number of sturgeon seen in those waters and here, as in Virginia, many and often fanciful stories are told about the fish being so numerous that they jumped into open boats. Even as late as 1850 it was not an uncommon occurrence for passengers on the ferry to see several sturgeon during a single trip between Camden and Philadelphia. In the Great Lakes, on the Pacific coast, in Maine and southward from the Chesapeake, the records tell the same story of sturgeon in wonderful abundance. Yet, strange as it may seem, in those days of none too abundant food supply, the sturgeon apparently was not often eaten until many years after the colonies were established. It is not known just when this species was first made the object of a regular fishery. The unsuccessful Virginia experiment in 1626 was undoubtedly the first attempt. But after the abandonment of that venture there is no record of a regular sturgeon fishery until more than a century later. There is a tradition that before the revolution ​market-men at Trenton, then an important fishing center, packed sturgeon in barrels, shipping them to New York and to Philadelphia by ox team. But until long after the colonial period, even in these places the roe was regarded as worthless except as feed for hogs or as bait for other fish. Furthermore, few people of the better class would eat the flesh, it being the food of servants and negro slaves. The reason for this prejudice is not recorded, but it is not unlikely that it was similar to the early prejudice against the Connecticut River shad on the ground that it was food for Indians. It is true enough that this objection, though equally applicable, did not prevent the colonists from consuming large quantities of oysters. But the difference in the edible qualities of oyster and sturgeon combined with the no less great abundance of the more highly esteemed shad, might readily explain the inconsistency. At all events, that the strong prejudice did exist is beyond question, hence there seems to be room for some doubt about the importance of this Trenton fishery of the colonial period.
In the "History of the Fisheries and Fishing Industries of the United States," edited by G. Browne Goode, it is said that a large sturgeon fishery, employing a score of vessels in some years, was carried on in Maine during the early part of the eighteenth century, but was not followed continuously. The account does not state to what use the products were put nor where they found a market. Again in the first quarter of the last century a company of men located on a small island in Casco Bay and began fishing for sturgeon, sending the flesh in kegs to the West Indies. The business was soon suspended for unknown reasons, however, and although there was an abundance of sturgeon in the Kennebec there was no further attempt to utilize them, except for occasional home use, until many years later.
Despite these various experiments at sturgeon fishing in different localities, the strong prejudice against the sturgeon flesh appears to have precluded the possibility of developing any regular market, and so prevented the growth of any important industry, until after 1850. It seems probable that the first approach to a regular and permanent fishery was developed in the Delaware River region. About 1830 and later, three Pennsylvania fishermen made a practise of taking sturgeon with nets and harpoons near the present town of Bristol, Pa. They also did some fishing about Dutch Island, near Bordentown, while on the other side of the Delaware a gill-net fishery was begun in 1853 at Penn's Grove, New Jersey. That the occupation here was not very remunerative, however, can be seen from the fact that the fish rarely sold for more than 30 cents each and often as low as 12$^1$⁄$_2$ cents.
About the same time, a third attempt was made in the Kennebec ​by representatives of a Boston firm, their object being to put up the roe for caviar and manufacture oil from the bodies. No difficulty was experienced in securing a supply of fish, 160 tons being caught the first season. The oil obtained was of excellent quality, but the experiment with the roe, one of the earliest in the country, was a failure, and after two seasons this venture went the way of its predecessors.
The Delaware River industry, evidently as a result of its proximity to New York and Philadelphia, where more convenient markets could be found among the foreign population and poorer classes, appears to have struggled along with a more or less precarious existence until about 1860. A few years prior to that date, the smoking of sturgeon flesh had been begun on a small scale in New York, and was followed by a similar custom in Philadelphia. Smoked sturgeon made a fairly good substitute for smoked halibut, and in this way a more or less regular demand for the flesh was for the first time created in the cities, being supplemented by the growing "wagon trade" carried on by peddlers who carted fish through the country districts. The preparation of sturgeon roe for caviar had also been done successfully on a commercial scale and was perhaps even a more important factor in promoting the growth of the fishery. But as an important industry, the sturgeon fishery of Delaware River and Bay can not be said to have originated much before 1860 to 1870, at which time, so far as the records show, the Hudson River was the only other place where it gave promise of attaining extensive proportions. Maine was once more the scene of a sturgeon fishery in 1872, when local fishermen engaged in it, giving place two years later to a regular crew, headed by New York fishermen, catching and buying for the New York smoking and caviar establishments. Important fisheries in the Hudson River existed prior to 1880, supplying local demands or the markets in Albany and New York. The former city is said to have taken such quantities of the flesh that it came to be known locally as "Albany beef," like the sobriquet "Charles city bacon" applied to sturgeon meat on the James River, in Virginia. The Maine fishery, however, ceased to be important after five or six years, and never was revived, and the Hudson industry had declined greatly before 1880, because of the scarcity of fish. During this same period, Delaware River fishermen had developed a regular fishery for sturgeon about the mouths of the larger rivers along the South Atlantic coast, the most important localities being Albemarle Sound, Savannah River and Winyah Bay. But regular fishing was also prosecuted near the mouths of the Altamaha, Satillas, Ogeechee, Edisto, Santee and the various streams ​entering Winyah Bay.In most cases the fishermen were from northern localities, going south to engage in the industry before the season opened in Delaware Bay, and sending their catch to the Savannah market, or to New York and Philadelphia, via Charleston or Savannah.
In other localities, however, the sturgeon was somewhat slower in being rid of the strong prejudice against it, to which was added in many cases the bitter enmity of the fishermen because of the damage done to their nets by this powerful fish. The salmon fishermen of the Columbia River despised it as a worthless, destructive fish, and for many years whenever taken in the nets a sturgeon was usually killed or thrown out on the bank. Along the shores of the Great Lakes sturgeon were not used very much for food until after smoking of the flesh began at Sandusky about 1860, experiments in making caviar having been tried at that place five years earlier.Before that time they had been so little valued that when it was possible to sell them they would not bring over 10 cents apiece, while in most cases they were regarded as a nuisance, usually being taken out and thrown away. As late as 1872, in fact, sturgeon were taken in great abundance every autumn in the nets of the Green Bay region and were almost universally pulled into the boats and consigned to the offal heap. From Virginia, also, comes the statement that less than three decades ago the roe was thrown away or used for fish bait, and such great quantities of meat were taken in the Potomac that there was absolutely no sale, the fish being piled like cordwood on the shore and farmers called on to cart them away for fertilizer. In the face of these conditions, however, the sturgeon fishery by 1880 had become an important branch of the fishing industry in the Middle and South Atlantic States and in the Great Lakes. Successful smoking of the flesh and its use as a good substitute for smoked halibut had overcome much of the early prejudice and established a small, but growing, market for sturgeon meat, while the manufacture of isinglass from the bladder and, most potent of all, the increasing European demand for caviar, aided materially in establishing the industry on a profitable basis. Instead of being thrown out in heaps to rot as before, the multitudes of sturgeon in the Great Lakes were now turned to profit by the fishermen. Where in 1860 the sturgeon had supported only a tottering industry, confined largely to the Delaware River region, the year 1880 marked an industry widespread in its range and yielding nearly 12,000,000 pounds of products annually.
​For nearly two decades after 1880 the animal yield of sturgeon products did not fall below eleven or twelve million pounds, but as season followed season the same areas were not contributing the same proportion of the total. The accompanying table shows the catch for the various districts in different years. In 1880 the Great Lakes,
Statistics of the Sturgeon Fishery
Ref. 19
Ref. 20
Ref. 21
Ref. 22
owing to the vast abundance of sturgeon in the shallow and warmer waters of Lakes Michigan and Erie, yielded more than three fifths of the total for the United States. Although complete statistics for the entire country are not available for any single year during the decade following 1880, there is ample reason for believing that the industry expanded and the products increased rapidly for several seasons. For example, the catch in the Lakes was only 410,000 pounds smaller in 1885 than it was in 1880, and in 1888 the chief coastal areas, the ​Middle Atlantic, South Atlantic and Pacific coast states, yielded an aggregate of nearly eight and a half million pounds as compared with less than four and a half million pounds in the earlier year. Every pound of this increased coastal yield in 1888, however, was due to the expansion of the Delaware River and Bay fishery, which in that year produced over 6,400,000 pounds. But even this phenomenal catch is said to have been smaller than it had been a few years before. It seems safe to conclude, therefore, that in 1885 the combined sturgeon catch in the Lakes and in the Delaware region alone was not less than 25 per cent, greater than the total product of the whole country in 1880. If this be true the total catch in the United States must have ranged at least somewhere above 16,000,000 pounds in 1885. It was the demand for caviar in European markets and especially in Germany which had more than anything else made the fishery profitable and caused it to rise almost in a single decade, 1875-1885, to an industry of important proportions among the valuable fisheries of the country.
By 1890, almost every district was beginning to show the effects of the vigorous fishing which had swelled the total catch during the early years of the decade. The declining supply was most marked in the lakes, where the catch had fallen off by nearly three million pounds in five years. The Middle Atlantic States then stood first, the quantity taken from the comparatively small expanse of Delaware Bay exceeding the entire lake catch by nearly a million pounds, the total being over three times as great as it had been in 1880, but distinctly less than the amounts reported in the intervening years. In the South Atlantic States also there had been extensive declines in the sturgeon products, but since the catch in these areas increased to a marked degree in subsequent years it seems necessary to suppose that the low catch of 1890 was due in part, at least, to other causes than scarcity of fish. Along the Pacific coast, on the other hand, marked expansion was taking place in the years preceding and subsequent to 1890, as the result of a successful sturgeon industry established on the Columbia River in 1888. Vast quantities of sturgeon had been observed by the fishermen ever since the salmon fishery had begun two decades before, but all that time the sturgeon had been looked on as a nuisance and "in most cases was knocked on the head and set adrift in the river." The abundance of the supply available can be seen from the fact that two years after the business was started the catch rose to nearly 1,700,000 pounds, and to more than 3,000,000 pounds in 1892. This important increase in the Pacific coast district, combined with the greater extent of the Delaware ​fishery as compared with ten years before, accounts for the greater yield for the country in 1890.
Statistics of the sturgeon fisheries in the scattered inland waters of the country were collected for the first time in 1895 and added a little over 2,250,000 pounds to the total. The major portion, over two thirds, of this quantity came from a single area—the Minnesota waters of the Lake of the Woods. The same year showed continued large catches in the waters of Washington and Oregon, though a comparison of the totals with the figures for a few years before indicates a growing scarcity of fish and an impending decline. The Carolinas and Georgia, however, were again yielding as much as formerly, having recovered at least temporarily from the low condition of 1890. The activity in these three areas helped to offset the appalling decline which had continued uninterrupted in the lake region and the Delaware district, as indicated by the statistical surveys of 1897. The lakes in 1897 produced scarcely more than one fourth as much as they had in 1890, and New Jersey, which alone had yielded over 3,600,000 pounds in 1890, barely exceeded 1,000,000 pounds seven years later. On account of these tremendous losses in the supply from the waters of early importance, the total yield of the country had fallen only a little more than half a million pounds below the figures for 1880, but over a million and a half pounds below the total for 1890, and at least six million pounds below the catch of 1885.
Two factors had played a leading part in maintaining the industry against such odds as are represented in the depletion of the Great Lakes and Delaware River sturgeon. First of all the rising price of caviar was a powerful incentive to pursue sturgeon fishing with increasing vigor wherever a profitable catch could be made. Caviar which had brought from $9 to $12 per keg of 135 pounds in 1885, was worth $20 five years later, $40 in 1894, and before the end of that decade had risen above $100 per keg. Sturgeon roe was no longer fish bait and feed for hogs, and few sturgeon found their way to the offal heap, at least, until after the precious ova were removed. Flesh too was mounting upwards in price, reaching as high as 12$^1$⁄$_2$ cents per pound in 1896, where a decade and a half before sale had often been impossible at even one cent per pound. From 1882 to 1884 female sturgeon would bring as high as $2 each at the wharf, whereas fifteen years later the usual price was $30 to $35 each. In the spring of 1899, for example, 96 sturgeon at Bayside, New Jersey, brought $3,923, an average of a little over $40 apiece. Nowhere else in the whole ​annals of commercial fisheries is there a parallel to this case of the sturgeon, rising as it did in less than a quarter of a century from a fish despised and ruthlessly destroyed on all sides to the highest rank of commercial value.
The high prices for caviar resulted in continued operations in the old localities even in the face of greatly reduced hauls. This condition is nowhere better illustrated than in the Delaware district, where the average catch per net dropped from 60 fish in 1890 to less than half that number six years later. Yet in 1897 nearly 1,000 fishermen were operating over 150 miles of gill nets in the sturgeon fishery of Delaware Bay and the number of boats employed had actually increased. At the same time operations were extended and expanded in every available new area to supply the growing demand and to profit from the rapidly rising prices. The sturgeon fishery in the Gulf States was begun at this time because of the increasing scarcity of the species in northern waters. The south side of Long Island was the scene of an important fishery begun in 1892, producing more than half a million pounds of products five years later, while the yield from interior waters, though steadily decreasing, was annually forming a larger proportion of the total output of the country. Only by most vigorous means was the total extent of the industry maintained anywhere near its former level, while the fishermen to eke out profits were endeavoring to utilize more of the sturgeon by the manufacture of oil and fertilizer from the carcass.
By 1897 the sturgeon fishery attained the highest point of its commercial value, over half a million dollars, while at the same time it appears to have reached its limit of endurance under the strain of incessant demand placed upon it. In the decade elapsed since then there has been only decline—decline almost universal and astounding in its extent. In many places, the sturgeon is practically extinct and in others, where once important fisheries were prosecuted, the industry is nearly abandoned. New York and Pennsylvania waters have almost ceased to yield sturgeon products despite the half million pounds from Long Island in 1897. The same condition appears in the Carolinas, while the species has entirely disappeared from the waters of Eastern Florida and Oregon. On the Pacific coast, as a whole, where more than 3,000,000 pounds were taken in 1895, less than four per cent, of that quantity was obtained in 1904. The Middle Atlantic area as a whole and the Great Lakes are now yielding less than one tenth the amount caught two decades ago. Lake St. Clair, which alone gave nearly a million pounds in 1880 has not produced more than 10,000 ​pounds in recent years, while the catch in Lakes Michigan and Erie has fallen to about one sixtieth of its former proportions. In the Delaware River district, the most prolific of all the sturgeon grounds ever developed in this country, the depletion of the supply has gone almost to the point of extinction. The total amount yielded from the nets of the three states bordering the river and bay has dropped from more than 5,000,000 pounds in 1890 to less than 350,000 pounds in recent years. A quarter of a century ago these waters still literally teemed with sturgeon, and it was impossible to dispose of all that could be caught. Then it was not an uncommon thing to see 1,000 or more sturgeon on the wharf at Bayside, New Jersey, with shipments of five or six carloads in a day to New York or Philadelphia. In recent years to see a score of sturgeon on the wharf at one time has been a rarity enough to bring the fishermen from miles around to see them, and if five or six boxes are shipped at the same time the shippers think they are lucky. Less than twenty years ago 4,000 to 5,000 kegs of caviar were shipped annually from the Delaware district and dominated the market under the name of Russian caviar. But the total caviar output had fallen to 726 kegs in 1899, and at Delaware City, an important center, where 422 kegs of caviar were prepared in 1895, only six kegs were obtained in 1901, with even less since then, while the price has been soaring above $1 per pound. It is a condition without parallel in the annals of fishing.
With the single exception of the smaller rivers entering the Gulf of Mexico, where the fishing for sturgeon dates only since 1897, all the grounds show evidence of the same rapid depletion. On every hand, declines of 90 to 95 per cent, in the last decade or two mean only the one thing—that the end of the sturgeon is near unless the most active and rigorous protective measures are speedily adopted.
This amazing depletion of a fish once "marvelously abundant" must be regarded largely as a natural or at least inevitable outcome of the character of the fishery itself. More or less weight must, of course, be given to the amount of wanton destruction of the sturgeon by the river and lake fishermen of successive decades before the sturgeon fishery was established on a commercial scale. Certain injurious and wasteful methods of fishing have also been employed at times, the worst of which was the use of small mesh nets both by sturgeon fishermen and by others, destroying many young sturgeon, the use of the three-pronged grappling hook dragged over the spawning grounds, particularly at the eastern end of Lake Erie, and most of all the unrelenting pursuit of the fish during the spawning season. The object of the ​fishery, however, has always been chiefly to obtain the roe for caviar. Hence the spawning time was the most favorable period for profitable operation, and the fishermen, with their characteristic disregard for the future, by incessant fishing practically eliminated natural reproduction. When the lake whitefish supply began to fail the fishermen were required by law to return the spawn to the spawning grounds, and when the Atlantic coast shad showed signs of depletion vigorous work at artificial propagation was largely capable of counteracting the effect of too much fishing. But the case of the sturgeon was quite different, in that the profitable prosecution of the fishery depended mainly on the amount of roe secured. In many cases, in fact, no other portion was utilized until comparatively recently, when the price of the flesh advanced. Obviously then a most serious difficulty stood in the way of the adoption of those measures which had benefited fisheries for other species. The high value of the hard ova to the fishermen and their inability to use the soft or ripe ova in caviar have meant the most vigorous efforts to secure the roe before it became soft. The United States Fish Commission, and the states of Pennsylvania, New Jersey and Delaware, have repeatedly tried sturgeon hatching individually and in cooperation, but the difficulty experienced in securing ripe spawn and milt at the same time has brought failure. The fact is, in the Delaware district, at least, the species is so nearly extinct, and males so scarce, that even when ripe ova are secured a male may not be taken for several days or too late to be of any use. It is hard to see how this condition can be easily remedied. With artificial propagation more or less impracticable and natural reproduction reduced to an absolute minimum, the fate of the sturgeon is obvious.
It is true, however, that some efforts have been made to prevent the complete extermination of the sturgeon and to protect the existing remnants of the formerly important fishery. The principal efforts have been made through legislative action placing certain restrictions on the operations of the fishermen. These restrictions fall into two groups, first, making it unlawful to take sturgeon under a given size, and second, prohibiting all sturgeon fishing at certain seasons. The states bordering on the Great Lakes furnish the best illustration of the first group of laws. Ohio in 1896 prohibited the capture of sturgeon less than 3$^1$⁄$_2$ feet long; Pennsylvania passed a similar law in 1901, and New York adopted a minimum length of 3 feet in 1902. Michigan and Wisconsin, on the contrary, based their restrictions on weight, the former, in 1897, setting 15 pounds as the lawful size, and the latter, in 1903, prohibiting the capture of sturgeon under 8 pounds.
These laws do not seem to have produced the desired result or in ​fact any important result at all, for the fishery has continued to decline steadily since the laws were enacted. The trouble, however, lies not so much in the provisions of the law itself, as it does in the difficulty of adequate enforcement. The Lake areas are in this respect no different from other localities, since laws protecting the young sturgeon of the Delaware have been in operation from 1891, yet the fishery in those waters has declined at an extremely rapid rate, and to a greater extent than in almost any other region.
The other alternative of statutory protection, the close season, has received less common trial because the only time at which a close season has any value is during the spawning period, and at that time the fishery is most profitable. The scarcity of such laws is probably due to the fact that restrictive legislation affecting the fisherman's profits has always been notoriously difficult to pass. Georgia, however, in 1901 prohibited catching of sturgeon in all waters of the state for a period of five years. Minnesota in 1905 adopted a close season from March 1 to May 1 of each year, but at the next session of the legislature the Georgia example was followed in the provision for a close season at all times until June 1, 1910. This sort of law seems to afford the only real remedy for existing conditions. Complete prohibition is, of course, much easier to enforce than partial prohibition, because where sturgeon roe can be legally taken at all the carcass can be disposed of readily and it then becomes a difficult matter to prove that the fish from which the roe was taken was undersized or underweight.
With the difficulties confronting artificial hatching and the adequate enforcement of restrictive measures, the future of the sturgeon fishery depends on the absolute cessation of fishing for a period of years during which the supply can be replenished through natural reproduction. Otherwise the total extinction of the species is as inevitable as was the depletion of the supply. This chain of conditions is not peculiar to the United States, but has prevailed in all the older localities wherever the fishery has been prosecuted. Yet it seems scarcely comprehensible that a fish so widely distributed through the country, so abundant, and so little used less than three decades ago, has so rapidly disappeared that the end is already in sight. The higher the price of caviar, the more vigorous the pursuit of the sturgeon and the more quickly the end will come. Under the present conditions it is only a question of a few years until the day of the sturgeon fishery will have passed.
* ↑ Burk, J. D., "History of Virginia," Vol. II., p. 17.
* ↑ Beverley, Robert, "History of Virginia," pp. 117-119.
* ↑ Watson, J. F., "Annals of Philadelphia," p. 46.
* ↑ Fishing Gazette, July 21, 1906, p. 679.
* ↑ U. S. Fish Commission Report, 1899, p. 370.
* ↑ Goode, Vol. V., Sec. 1, p. 699.
* ↑ U. S. Fish Commission Report, 1899, p. 370.
* ↑ U. S. Fish Commission Report, 1899, p. 370.
* ↑ Goode, Vol. V., Sec. 1, p. 699.
* ↑ Goode, Vol. V, Sec. 1, p. 659.
* ↑ U. S. Fish Commission Bulletin, 1891, p. 355.
* ↑ Goode, Vol. V., Sec. 1, pp. 617-625.
* ↑ Goode, Vol. II., p. 506.
* ↑ U. S. Fish Commission Report, 1887, p. 249.
* ↑ Loc. cit., p. 263.
* ↑ U. S. Fish Commission Report, 1872-73, p. 10.
* ↑ Fishing Gazette, January 20, 1906, p. 56.
* ↑ 18 Statistics from following sources: Goode, Vols. II., V., Sec. 1. Report of the U. S. Fish Commission, 1888; 1893, p. 146; 1895, p. 495; 1896, p. 576; 1899, pp. 109, 175, 372-80; 1900, pp. 200, 319; 1901, pp. 511, 580; 1902, pp. 440, 484; 1903, pp. 348, 416; 1904, pp. 648-51. Bulletin of U. S. Fish Commission, 1890, p. 78; 1891, p. 281; 1894, p. 350. Fisheries Documents 609, 620; Statistical Bulletin 188.
* ↑ 19 Statistics are for years as follows: New England, 1889; all others, 1890.
* ↑ 20 Statistics are for years as follows: New England, 1898; Pacific coast, 1895; Great Lakes, 1899; Interior Waters, 1895; others, 1897.
* ↑ 21 Statistics are for years as follows: New England, 1905; Middle Atlantic, 1904; South Atlantic and Gulf, 1902; Pacific Coast, 1904; Great Lakes, 1903; Interior Waters, 1903.
* ↑ 22 No values given.
* ↑ 23 U. S. Bureau of Fisheries Report, 1904, pp. 649-51.
* ↑ U. S. Commission Report, 1888, "Statistical Survey of the Coast Fisheries of the United States."
* ↑ U. S. Fish Commission Bulletin, 1888, p. 278.
* ↑ U. S. Fish Commission Report, 1899, p. 372.
* ↑ U. S. Fish Commission Bulletin, 1891, p. 281.
* ↑ 28 U. S. Fish Commission Report, 1893, p. 250.
* ↑ U. S. Fish Commission Report, 1895, p. 495.
* ↑ U. S. Fish Commission Report, 1896, p. 576.
* ↑ Bureau of Fisheries Report, 1902, p. 460.
* ↑ U. S. Fish Commission Report, 1899, p. 379.
* ↑ Pennsylvania Fish Commission Report, 1900, p. 171.
* ↑ U. S. Fish Commission Report, 1899, p. 371.
* ↑ Ibid., pp. 379-80.
* ↑ Bureau of Fisheries Report, 1903, pp. 443, 445.
* ↑ Bureau of Fisheries Document 609, p. 29.
* ↑ U. S. Fish Commission Report, 1888; 1896, p. 576; 1899, pp. 109, 372; 1901, pp. 511, 580; 1903, p. 345; 1904, p. 648.
* ↑ Pennsylvania Fish Commission Report, 1900, pp. 170-71.
* ↑ Bureau of Fisheries Report, 1903, pp. 443, 455.
* ↑ Bureau of Fisheries Report, 1902, p. 460. Pennsylvania Fish Commission Report, 1905, p. 64; 1906, p. 23.