Part 2

It might be very proper to protect the mussels during the active breeding season, if such a season could be defined; but, as a matter of fact, the various species of mussels in any particular stream have different seasons of breeding. The mussel industry is based upon a considerable number of species of economic mussels. There is a group which has a short breeding term during the summer months. Such are the species known commercially as "niggerhead," "pimple-back," "monkey-face," "maple-leaf," "blue-point," "three-ridge," etc. The "washboard" seems to have an intermediate breeding term during the early fall, though it may be that in some cases it carries its spawn into the winter. Many of the more important species of mussels have a long term of breeding; in the latter part of the summer and in the early fall the eggs are deposited into brood pouches within the shell of the female, and there, after they hatch and develop, they are carried over the winter, to be liberated in the spring and early summer.[A] Of this kind are the "mucket," "sand-shell," "pocketbook," "butterfly," and others.

[A] Possibly these mussels liberate glochidia to a limited extent during the fall and winter; but the general statement is well founded.

In view of the variety of commercial mussel species and the diversity of breeding seasons, it does not appear practicable to determine upon a closed season that will accomplish its particular purpose. The Illinois law prohibits the taking of mussels in any navigable water in that State between the 1st day of October and the 1st day of April; but, as illustrating how such a measure may apply in a particular case, practically all of the mussels in the principal river of that State--the Illinois River--are short term or summer breeders, spawning some in June, July, and August, others in October and about that time. Only a few carry the spawn, after its development, through the winter.

The principal objection to an enforced interruption of the fishery during a period of months is that it deprives the mussel fishermen of the right to earn a living by their profession during a portion of each year. This objection has real weight, and should be overborne only by decided advantages to be gained from a closed season.

_Restricting the methods of fishery._--The principal implements for taking mussels are the crowfoot bar, the rake, the fork, the tongs or scissors fork, the dip net, and the dredge. These several pieces of apparatus are variously adapted to conditions of depth, rate of current, and character of bottom, as well as to the aptitudes and customs of the fishermen. Before a method should be prohibited it should be known that it can be replaced by one of the more suitable methods, or else that it is so positively injurious as to require its elimination. The only implement of capture against which complaints are generally made is the crowfoot hook, but this is the only method in general use which is adapted for taking mussels in the deeper water, and it is probably in more common use than any other method. Perhaps in time improvements upon this hook will be adopted to lessen its injuriousness, or other methods capable of replacing it will be better known. In the light of present conditions it would work an unnecessary hardship upon a very large number of fishermen to prevent its use, especially when it appears that the protection of the mussels can be accomplished by methods more equitable to all concerned.

Still other measures have sometimes been advanced looking to the limitation of the number of shellers to be permitted to work within a given territory or to the leasing of shelling rights. Since such proposals have not yet been offered in connection with any properly worked-out plan by which serious injustice would be avoided and the interest of the public safeguarded they may be dismissed with the remark that it is not simply the protection of mussels that is desired but the protection of the mussels for human use without interference with common human rights. The absence of inherent wrong in an idea does not commend it if it carries within itself the seeds of its own defeat by a method of application, or a want of method, that allows opportunity for manifestly unjust and intolerable conditions to arise.

There remains to deal with the necessity for the two measures that are advocated and to discuss the methods of application. This can be more adequately done in distinct sections.

SIZE LIMIT--NECESSITY AND APPLICATION.

EXHAUSTIVE NATURE OF THE FISHERY.

The necessity for imposing restrictions upon the size of mussels to be removed from the beds is brought out more clearly by the photographs than could be done by any lengthy discussion. All of the shells shown in plates I and II were actually taken for market, sold, and shipped to the factory. The smallest ones (in the three upper rows on plate I) were not wanted at any factory; they were bought only because the fishermen had thrown them into the piles along with the larger shells, "to add weight." Most of the very smallest shells, those under 1 inch in length, are subsequently lost in handling, by falling through the forks or otherwise wasting as they are thrown into the car or from the car to the bin. None of the shells in the three upper rows of plate I would ordinarily be used by any manufacturer. It is true that some of the shells shown have had one blank cut out, and these were actually cut at a commercial plant, but the instance was a very rare one and was certainly unprofitable. Even if the manufacturer desired it, the cutters will not handle shells from which only one blank can be cut, since the waste of time outweighs the saving of material.

Consequently all shells less than about 1½ inches in length, no matter what the quality, are thrown into the discard. _There can be no difference of opinion as to the pure wastefulness of taking shells of this size._

The shells shown in the illustration are not the smallest that could be found. Some shells observed in the fishermen's boats were only one-half inch in the greatest diameter. Out of the water these are entirely without use. The fisherman who saves them, thinking that they add weight to his heap, would doubtless be surprised to learn that he would have to handle several times and clean 200 of such shells to add 1 cent to his earnings, for it would take nearly half a million of them to make 1 ton.

The shells in the fourth and fifth rows, counting from the top in plate II, are used at the factories when received, and are sometimes particularly favored where the quality is as good as in those from many Arkansas rivers, and the shells will yield two or three blanks of 16 to 20 lines. Such blanks are of a suitable thickness and work up economically besides having a good quality. Some of the shells in these two rows show how blanks of 18, 16, and 14 lines are worked out, a "line" in button measure representing the fortieth part of an inch.

The use of shells taken between 1½ and 2 inches in greatest diameter does not, therefore, like the marketing of those under 1½ inches, represent absolute waste, but it does denote relative waste or real short-sightedness from the economic point of view. Shells of this size will average about 30,000 pairs to the ton, while mussels of such a practical size as 2½ inches will average only 15,000. The number of blanks obtained from a ton of shells of the latter size would be just the same as from a ton of the smaller shells, notwithstanding that only half as many shells are handled. _We are thus, when using the smaller shells, depleting the mussel beds at twice the necessary rate without any corresponding advantage._

WASTE ILLUSTRATED.

There is given below a table that will repay careful examination as illustrating the wastefulness of using the small shells. While the figures must be understood to be only approximate, they are based upon careful weights and counts of a number of shells from several localities. The shells were all "niggerheads" and were all obtained after shipment to factories.

The first two columns show the limits of size for each lot used, the greatest diameter being the basis of measurement.

The third column shows the approximate number of pairs of shells composing a ton, the unit of purchase; multiplying this number by 2 would give the number of single shells per ton.

In the fourth column there is given, in the case of the critical sizes, the number of 18-line blanks readily taken from a single shell (which is one-half the number yielded by a pair of shells, or an individual mussel).

The fifth column indicates the number of gross of blanks, by computation, yielded by a ton of shells. This computation is based upon the cutting of 18-line blanks (not the larger 20-line blanks that have been taken from some of the larger shells in the illustration). Some of these shells are cut excessively close to the tips, on account of taking too many larger line blanks. It must be understood that different sized shells are adapted for different lines of buttons. The data herein is for comparative purposes only.

TABLE OF SIZES, WEIGHTS, AND BUTTON PRODUCTION FOR NIGGERHEAD SHELLS (APPROXIMATE FIGURES).

+-------------------+----------+-----------+-------------+---------------+ | Longest dimension.| Number of| 18-line | Quantity | | +-------------------+ mussels | blanks | of blanks | Refer to | |Greater Less | per ton. | per single| per ton. | illustration. | | than-- than-- | | shell. | | | +-------------------+----------+-----------+-------------+---------------+ | Inches. Inches. | | | Gross. | Plate I-- | | | | | | | | ¾ 1 | 174,000 | | | 1st row. | | 1 1¼ | 110,000 | | | 2nd row. | | 1¼ 1½ | 55,000 | | | 3rd row. | | 1½ 1¾ | 33,000 | 2 | 917 | 4th row. | | 1¾ 2 | 26,000 | 3 | 1,008 | 5th row. | | 2 2¼ | 20,000 | 4 | 1,111 | 6th row. | | 2¼ 2½ | 15,000 | 5 | 1,042 | 7th row. | | 2½ 2¾ | 10,500 | 6 | 875 | 8th row. | | | | | } | { | | 2¾ 3 | 8,500 | [B]7-8 | }Gradually | {Plate II-- | | 3 3½ | 6,200 | [B]10 | }diminishing| {1st row. | | 3½ 4 | 4,000 | [B]12 | }to less | {2nd row. | | 4 | 3,200 | [B]14 | }than | {3rd row. | | | | | }650 per | {4th row. | | | | | }ton. | { | +-------------------+----------+-----------+-------------+---------------+

[B] At the time of making this table only a few of the larger-sized shells were available, so the estimates of blanks are less accurate.

It may be seen from the table that a marketable ton of niggerheads could be composed of the shells of 3,200 or of 33,000 mussels, according as the shells were 4 inches in length or only 1½ inches. As a matter of fact, no marketed ton is ever composed of mussels of an exactly uniform size; furthermore, the extremely large niggerhead shells are very rare and generally not very desirable on account of inferior quality and disproportionate waste. A ton of shells from a region of depletion will also include a number of the smallest and not strictly marketable shells.

Now, let us take a concrete illustration: Several counts of mussels gathered by shellers in the white River near Clarendon, Ark., were made in October, 1913; from these an average was taken that fairly represents the catches being made at that time in that region. It was found that 60 per cent by number of the shells taken were of a size less than 2 inches in greatest dimension; also that a ton of shells comprised 20,500 pairs, of which 12,300 were less than 2 inches. Now, it is evident that if these smaller shells were returned to the bed we would be depleting the bed less than one-half as fast as at present. This would be the substantial advantage that such a size limit would have to the mussel beds; and any advantage to the mussel beds is an ultimate advantage to the fishermen, manufacturers, and all others in any way dependent upon the perpetuation of the mussels. Under the working of a 2-inch size limit, 60 shells out of every 100 then being taken on the niggerhead beds of that vicinity would have been thrown back. This seems to be asking a good deal, but not so much as at first appears, for the undersized shells constitute only 38 per cent of the weight or selling value of the shells taken.

On the other hand, both sheller and manufacturer would be saved the trouble of handling over and over again an unnecessarily large number of shells. A ton of shells (from the same locality) comprising only those above 2 inches in greatest dimension would contain about 13,000 pairs, or 37 per cent less than the number now found in a ton (20,500), while these shells, the smallest ones being eliminated, would produce at least 10 per cent more buttons of corresponding sizes.

SIZE LIMIT IN RELATION TO ECONOMY.

The figures given above are, of course, based upon counts and computations of shells from a particular locality and must not be assumed to have any general application, but the facts and principles derived do have a universal bearing. If such a size limit as 2 inches is adopted, the saving to the mussel beds and to the future of all interested parties is out of all proportion to the immediate loss to any party; and even the immediate loss is to some extent compensated by the saving resulting from having to do with a lesser number of shells that yield a greater number of buttons per ton.

Undeniably some temporary sacrifice is entailed, but unless it be admitted that temporary sacrifice will be accepted, it is useless to consider any manner of restriction for ultimate benefit.

There is one point that is brought out in the table on page 14 that merits attention from the broad standpoint of economy. In all shells there is a proportion of unavoidable waste, since the entire weight of the shell can not be transformed into buttons. In very small shells we may expect an undue waste, on account of the fact that only one or two blanks can be cut out, leaving a larger bulk of shell in proportion to the number of blanks gained. On the other hand, in very large shells a high degree of waste is involved because of excessive thickness, which must be ground from the blanks, and because of the extra weight of the discarded portion. Somewhere between these extremes is the size of shell that yields the largest number of blanks as compared with the waste or the weight of shell that does not go into buttons. As shown by the data in the fifth column of the table, the shells a little above 2 inches in size are those (for this species) that make the best yield per ton for the small lines for which there is the greatest general demand.

REASONS FOR THE PROPOSED 2-INCH LIMIT.

Argument might be made in favor of a higher size limit as being still more favorable to the preservation of the mussels, but it is sufficient to say that the economic conditions would not justify a higher limit. At 2 inches a sufficiently severe restriction is placed upon the fishery, and to go further would be practically to prohibit the pursuit of shelling in so many localities that excessive hardship would be caused.

As consideration thus far has been given almost exclusively to the niggerhead shell, the question may well be raised, Will the same limit apply to other species of shells? The minimum size of 2 inches suggested can be taken as an absolute minimum, since there is no species of any importance for which it would be too high. This minimum would not, however, give the same degree of protection to the larger forms, such as the washboard, the bluepoint, and the mucket. Should a minimum size be fixed with particular reference to any one of these varieties, it would necessarily be a good deal higher.

In the present paper recommendation is made for this one-size limit alone, for the following reasons:

1. All conditions considered, it is the most appropriate limit that could be designated for the niggerhead mussel, which is at present the most important species of wide distribution, and which is, furthermore, the species most liable to rapid extermination. This and species closely like it, as the pigtoe, the pimple-back, and the maple-leaf, are chiefly those that are now being taken in the very small sizes.

2. The same size applies equally well to the related species just mentioned, as well as to the "hickory-nut," or "Missouri niggerhead," and the "butterfly."

3. The larger species, as the "washboard," "bluepoint," and "mucket," are generally so evidently valueless in the small sizes that shellers do not take them. At least it is not yet of observation that particular injury is being done to these species in this way.

4. To insure the least trouble of enforcement of the law, it is necessary that a minimum size be set, below which no shells of any species may be retained. There are many different species of commercial mussels, and some of them so intergrade as to make exact determination a nice matter in some cases. Distinct size limits for the different species would introduce peculiar difficulties into the practical workings of enforcement; it would be more troublesome to the sheller to observe the law voluntarily, and loopholes for evasion would more easily be found by the offender of wrong intent.

Should conditions in certain States or streams subsequently require a higher limit for particular kinds of shells, a supplemental limit may be fixed for designated species; but this could be done without affecting the application of a 2-inch limit as an absolute or universal limit below which no shells of any species could be lawfully taken. It is desirable that few different limits should ever be used, and it seems expedient to have but one size limit until the first legislation shall have been tried out.

DETAILS ESSENTIAL TO EFFECTIVE LEGISLATION.

In concluding this section emphasis may be laid on the value of certain details of legislation.

_Allowable margin of undersized shells._--While it may seem desirable that no undersized shell at any time should be taken away, nevertheless it is necessary to make allowance for a margin of unintentional error. Only if the shellers and buyers were to apply an instrument of measure to each individual shell would all possibility of error be eliminated. The sheller will naturally, after a few measurements, come to judge by the eye, and it is desirable that the law should be somewhat liberal, rather than too stringent in the allowance for mistakes. There should, accordingly, be a supplemental provision that if not more than 5 per cent of the shells by number (not by weight) of any bushel are found to be below the size limit, the law shall not be presumed to be violated.

_Illegal possession._--To be practicable of enforcement, the law should be so worded as to make it illegal not only to bring ashore or to offer for sale, but also to have in possession, fresh-water mussels or clams of a size less than 2 inches in greatest dimension. This one provision will obviate much unnecessary expense, as well as undesirable complications in the detection of violations and the prosecution of offenders. Furthermore, since buyers of the shells would be equally liable to prosecution, the effect would be to destroy the market for undersized shells, and thus in the most effective way to restrain the shellers from taking them.

_Method of measuring mussels._--It will be noted that the method of measure is stated as "in greatest dimension," with a view to eliminating every possibility of uncertainty or difference of opinion. Mussels are sometimes measured in length or width or height, but on account of the irregular form of mussel shells these dimensions are not always interpreted in the same way. In testing the blank-making capacity of a shell, commercial men sometimes measure the "width on the face"; that is, between the lateral hinge tooth and the lower margin of the shell. This measure can of course only be taken from an open shell, and therefore could not serve for our purpose. It is worth while to call attention to the fact that a 2-inch shell as measured in greatest dimension would be a good deal smaller than a 2-inch shell in commercial measurement.

An inspector would need to be equipped with an ordinary rectangular caliper. If a shell should be found to measure more than 2 inches in any linear direction it would be considered as above the size limit.

CLOSED REGIONS--NECESSITY AND APPLICATION.

In addition to the provision of size limits it is strongly recommended that certain portions of the rivers be closed for rest periods covering several years. It might be thought that in regions of extreme depletion the operation of a size limit would, by making the fishery less profitable, have the effect of causing a practical rest period, but this can not be expected, for, stimulated by the high price of shells and the ever-present hope of making a pearl find, the local shellers will hardly ever desist entirely from the fishery.

No better way of giving protection to mussels can be found than that of entirely stopping the shelling upon a series of beds, although the plan must be applied in such a way as not to reduce the supply of mussels unduly and suddenly and with as careful regard as possible to the established interest of communities.

INJURY TO SPAWNING MUSSELS AND TO YOUNG.

Some of the conditions that make a system of closed regions particularly advisable for the conservation of fresh-water mussels may be briefly mentioned:

1. It has been previously stated that some of the mussels are spawning, or with spawn, during any period of the year. Many of the most important species are spawning during the late spring, early and mid summer; other equally important species form their eggs in the late summer, when they become fertilized and develop into the glochidium stage, but the mother clam retains them in marsupial pouches within her shell during the entire winter and even into the summer. All species of mussels carry the eggs in the marsupial pouches during the process of development to the glochidium stage or longer, whether the period be for a few weeks or for a few months. In this condition the mussels are said to be gravid. It is readily observed that when gravid mussels are disturbed they frequently discharge the young, regardless of whether these are mature enough to be liberated from the parent or not; certain species, such as the niggerhead, are particularly likely to do this.

In the commercial fishery, therefore, not only is much spawn destroyed when large gravid mussels are captured, but it is quite probable that other mussels, disturbed on the bottom, though not captured, are caused to abort the young in an immature stage when they are entirely unable to complete the development without the parent.