G. Brown (George Brown) Goode.

The fisheries and fishery industries of the United States (Volume 1:1) online

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temperature too severe, they are impelled to desert it in a body for some other more favorable
locality.

ASSOCIATION OF MALES AND FEMALES. The male and female Lobsters generally associate
together in the same places, in about equal proportions ; but some curious exceptions to this rule
have been recorded. Capt. N. E. Atwood, of Provincetowu, Massachusetts, writing in 1866, states
that at that time about ninety per cent of all the Lobsters taken at Cape Cod were females, while
to the northward of Plymouth, on the west side of Massachusetts Bay, seventy-five per cent, of
all those captured were males. In and about Narragansett Bay, the fishermen claim that, during
July and August, about seven-eighths of the Lobsters taken are females, while during the balance
of the season the two sexes are about equally abundant. At Eastport, Maine, it is said that, as
a rule, more male Lobsters are taken than females. The above statements must be taken with
some grains of allowance, from the fact that the fishermen may not always be able to readily
distinguish between the two sexes, especially in the case of females not bearing eggs externally.
The rude and hasty manner in which they handle Lobstvrs would also preclude their discriminating
between the sexes with certainty, even though they were well acquainted with their anatomical
differences. Prof. 8. I. Smith examined quantities of Lobsters in the Provincetown market,
on two occasions, in August and September, 1872, without finding any decided differences in
the number of males and females. At Eastport, Maine, his examinations were made with even
more thoroughness, and with the same result. Professor Verrill also states that he has found
the males and females about equally abundant in market supplies received from New Lon-
don, Stouiugtoii, and Waterford, Connecticut. It is possible that, at some seasons, or under



790 NATURAL HISTORY OF AQUATIC ANIMALS.

certain conditions the males and females may live more or less apart from one another, but
the observations of scientific men indicate that this separation is not long continued, if it
occurs at all.

Mr. S. M. Johnson, of Boston, has recently assured us that the great preponderance of
females still holds true in the case of the Cape Cod region. Of the supplies received from there
at Boston, during the summer months, he feels certain, from long-continued observations, that
nearly if not quite ninety per cent, are females, and about seven-eighths of these bear spawn
externally. The section of coast from which these Lobsters are obtained extends along the outer
side of Cape Cod, from off Highland Light to Wood End Light. The Lobsters examined at
Provincetown, by Prof. S. I. Smith, in 1872, may have come from the bay side of Cape Cod, whence
Provincetown is supposed to receive its supplies for home consumption. The females may resort
to the shallow waters of the outer side of the cape to spawn during the season when the fishery
is carried on there, and this fact, if true, would readily account for their great abundance in that
region, as has been noticed for so long a time. The males and females approach and recede from
the shore together in the fall and spring.

WINTER HABITS. Fishermen generally agree that Lobsters do not trap as readily in the
winter as in the summer, even though the pots are set on what are supposed to be their winter
grounds. The reason assigned for this is that they are not as eager for food nor as active in
their movements in cold weather as in warm weather. This may be true to a great extent, but
we think it is equally probable that they are scattered over broader areas in the winter,
and their haunts are not as easily found. Evidence in proof of this idea has been recently
furnished us by a prominent Eastern dealer, who has kept large quantities of Lobsters in confine-
ment for the winter trade. The bottom of the area given up to their keeping is very muddy, and
the surface of the water sometimes freezes over to a depth of twenty -two inches. On the
approach of cold weather the Lobsters bury themselves in the mud, leaving only the long
antenna, the eyes, the tips of the claws, and perhaps a small portion of the front of the carapax,
projecting above it. Over some parts of the inclosure the water is so shallow that the exposed
ap|>endages can be readily seen from the surface. In these positions the Lobsters lie, presumably
all winter, unless disturbed, but whether or not they feed regularly has not been observed. If,
however, a hoop-net, properly baited, is lowered in front of them, they are not slow to enter it,
plainly indicating that they are still attracted by the bait, and it is just the same even after the
surface of the water has become a sheet of ice. As the ice breaks up toward spring, and after-
ward, while the drift ice still remains in this area, the Lobster.s become more timid and cannot be
caught. They also seem to re easily frightened at loud noises, and perhaps retire deeper into the
mud, for bait appears to have no attraction for them at such times. It is not possible, however,
that they could be influenced in this manner in deeper water.

It is a question which may never be definitely decided, whether Lobsters bury themselves in
the same manner in deep water as near shore. The temperature there would undoubtedly remain
more favorable to them than in shallow water, but many of those caught in the pots in winter are
core or less covered with mud.

MOVEMENTS. Lobsters hold quite closely to the bottom and seldom leave it, unless it may
be to escape an enemy, when they have been seen to execute a sort of swimming movement
backward, by means of their tail, darting up from the bottom, but quickly settling down again.
In moving about, they seem to skim over the bottom, using their four posterior pairs of feet,
the anterior pair, or big claws, being held rigidly out in front of them, with the tips pointing
inward and not far apart. The tail is also spread out and well expanded at the same time. The



<;HO\VTII OF THK i.oiisiKi:. 791

movements of Lobsters can be easily studied in the shallow cars in which the)' are kept for
market. pn>\ idi iiu there are not too many of them, as the bottom of the car should not be covered.
Their actions appear easy ami graceful, and their swimming powers may be tested by dipping
them out with a scoop-net and allowing them to fall back again. If allowed to fall in tail foremost,
a gentle tlap or two of the tail is sufficient to give the body the proper slope in the water so that
in .sinking it falls obliquely and reaches bottom by a more gradual motion than would be the case
it' it t't-11 directlv downward. During the downward movement the tail may or may not be kept in
mot ion. lint in case the specimen is thrown in head first or sidewise, if it be in good, lively
condition, it may give several vigorous flaps of the tail to right itself, and even swim off in one
direction or another for a distance of several feet before settling down as in the former case. As a
rule, however, the Lobster must be regarded as a bottom animal, exercising its power of swimming
only in cases of emergency.

We have made the above remarks to correct the current impression among many people that
the Lobster is a free swimmer and moves about in schools like many species of fish. For this
belief there is no foundation in fact.

GEOWTH, SHEDDING, ETC. Soft-shelled Lobsters occur at all seasons of the year, but appear
to he miicli le>s common in the winter than in the summer. The period of their greatest abundance
is from June to September or October. There is, therefore, no strictly defined shedding period,
and no possibility of determining, from present data, how often Lobsters shed. The shedding is
connected with the growth of the individual, and when the body has attained such an increased
volume that the bard covering or shell can no longer contain it, the latter breaks open, and the
Lobster comes forth in a soft state, and considerably enlarged. The possibility, therefore, exists
that in good feeding regions Lobsters may shed more frequently than in poor ones, for in the
former it is natural to suppose that the growth would be more rapid than in the latter. Absolutely
nothing is known, however, regarding this fact, and we must await future observations before
generalizing. During the younger stages, shedding goes on quite rapidly, but as the Lobster
increases in age it is probable that the shedding periods become ranch less frequent, and in very
old individuals may cease altogether. There is, however, no conclusive evidence to prove that
Lobsters ever attain a limit in size beyond which there is no further growth. Large individuals
are occasionally taken with a very thick and heavy shell so scarred and worn as to indicate a
prolonged and severe service. At times, the edges and angles of the shell and the exposed
prominences of the claws are completely worn away. Large Barnacles are often found upon the
shells of large Lobsters, and this fact is frequently cited as evidence that the Lobster had ceased
shedding, or at least had not shed for several seasons. But after having examined the slates
used by the United States Fish Commission as collectors for oyster spat, in Chesapeake Bay, in
1880, the writer can no longer regard this proof as very convincing. In the course of a month or
two the common Barnacle of that region, a species of Balanus, which had attached itself to the
slates in much greater abundance than the oysters, had attained a diameter of nearly an inch and
gave promise of growing much larger in a short space of time.

The process of shedding is very interesting, and has been frequently witnessed, although it
has never been minutely described by a competent observer. The following account has been
furnished us by Mr. S. M. Johnson, of Boston. As a preliminary, the carapax generally, but by
no means always, splits lengthwise along the middle of the back, often with a clean cut, quite to
the rostrum. Otherwise, the carapax merely separates widely from the abdomen, on the upper
side. The abdominal segments are the first to be withdrawn from their hard investment, ' and



1 This is contrary to what happens in the freh-wter Cray-fish.



792 NATURAL HISTORY OF AQUATIC ANIMALS.

as soon as they are free they are used in extricating the anterior portion of the body. The entire
process requires a great amount of violent struggling and pulling, the claws occasioning the
greatest difficulty, from being so much larger near the tips than at the base. Their fleshy
portion, however, becomes somewhat soft and flabby so as to be easily extensible, and capable of
being compressed down to a smaller diameter. The basal joint, called the thimble by fishermen,
breaks lengthwise across the narrowest side, where a groove naturally exists, and the base of
the next succeeding joint splits in the same way. The remainder of this second joint, and the
following larger one, are compressed and flattened upon the upper or inner side, where the
shell is thinner than elsewhere, the thin area being oval in outline, distinctly marked off from
the surrounding surface, and more or less marked with irregular, elongate, depressed lines.
Preparatory to shedding, this area, by the absorption of certain of its elements, becomes a thin,
soft, and extensible membrane, or may be entirely absorbed away. No other hinderances lie in
the way of the passage of the claws proper, which can be sufficiently compressed to work through
the next joint above them, although the latter remains hard and firm.

The layer of skin which is to form the new shell begins to take on its distinctive character
before the old one is cast, but does not harden to any extent. In this state it assumes a dark-
green color and gives rise to the common fishermen's term of " Black Lobster," which is used to
designate the Shedders. As the hard shell is cast, the soft skin exposed presents a velvet-like
surface. The process of shedding goes on rapidly, as often happens in lobster-cars where the
animals have been placed awaiting shipment to market. Lobsters which have had no marked
indications of shedding, when placed in the cars, have cast their coat within a day or two
afterwards. The hardening of the new shell also progresses rapidly. On many Lobsters the
newly forming shell can be seen inside of the old one, and more or less closely adhering to it.
It appears like a thin, semi-transparent, gelatinous lining of the old shell, and in some instances
can be readily peeled ofl' from it. Soft-shell Lobsters are sometimes called "Cullings," and those
in which the new shell has become slightly hardened are named " Paper-shells."

Just before and after shedding, Lobsters remain quiet, almost dormant, and more or less
concealed under stones or among seaweeds. Statements differ as to whether Lobsters seek
food while in the soft shell state. They are said to be captured in the traps at times, often
in great numbers; but as the food ordinarily preferred by them, and especially the baitings
of the traps, require hard surfaces for their mastication, we do not know how to account for
their presence in such situations. It is well known that hard Lobsters which entered the traps
in thai condition have shed therein, but in all such cases the cast skin should be present
when the traps are brought to the surface of the water. It is possible that soft Lobsters are
attracted into the traps by the smell of the bait, without the possibility of eating it. Most
of the soft-shell Lobsters handled, however, are captured before shedding. Very many are often
obtained in this way, but they are not considered good eating, as their flesh is described as
thin and watery. They are mostly used as bait, although it is stated that they are also sold to
the canneries.

Soft-shell Lobsters are more subject to dangers than the hard-shell, being helpless to protect
themselves. They are greedily devoured by many species of fish, especially the cod, and are
even said to be attacked by hard-shell individuals of their own species. When caught at this
time, even if returned at once to the water, the slight handling they receive is said to generally
kill them. Remaining, as they are supposed to, as much as possible out of harm's way, and
probably not feeding while in the soft state, the mortality is undoubtedly much less than as though
their habits continued the same.



i'i;o( i:ss OK siii:i)i)iN(i. 793

The length of time required for the hardening of the new shell has never been recorded from
observation. The fishermen's statements regarding it disagree, but the hardening goes on
probably more rapidly in warm weather than in eold, as in the, case of the edible Crab. A careful
observer at Wood's lloll, Massachusetts, says that the shell becomes quite firm iu the course of
twenty-four hours. After three or four das s it is supposed to be hard enough to enable the
Lobster to go in search of food, but the hardening probably continues aud tho shell increases in
thickness, even though it be very gradually, until the next shedding period.

A short time before shedding, tho Lobster is said to be very full of meat and in the best
possible eonditiou for eating. This would seem to result naturally from the increased quantity of
tlesli svliieli must urriimulate within the shell preparatory to the Lobster's assuming a larger size.
While shedding, but more especially while iu the soft state, after the Lobster has expanded to
its new size, the flesh is considered by most people as unpalatable, although it is probably as
harmless then as at any time. The fishermen abhor soft Lobsters as a rule, aud would not eat
them under any circumstances, but customers are occasionally fouud. One fisherman corresj>oud-
eut very aptly expressed his dislike for them iu the following terms: "They are sometimes eaten
by aristocrats, but never by .-." It seems very strange that soft Lobsters should be so unfavor-
ably regarded, when we consider that the edible Grab is iu its best condition just after shedding.

The female Lobster probably casts its shell soon after its spawn is hatched. The eggs are
attached so firmly to the swimmerets that they remain hanging to them even after the young have
gone forth, aud there is no other way of getting rid of this great encumbrance to the abdomen
than by shedding. This occurrence has been frequently observed in other species of Crustacea,
and probably happens iu the case of the Lobster. In fact, we have numerous recorded instances
of female Lobsters bearing spawn nearly ready to hatch, aud with the now shell in process of
formation. It is the common belief of lobstermen that Lobsters which have lost a claw, or been
seriously maimed in any way, do not shed until after the injury has been repaired.

Prof. G. O. Sars describes the process of shedding with the European Lobster, Homarus ml-
garin, as follows :

" The process of changing its skin is very tedious and dangerous for the Lobster, which may
be imagined when it is known that not only the outer shell is changed, but even some of tho
inner parts, e.g., the stomach-bag. The process occupies considerable time, and while it is going
on the Lobster is sick and utterly unable to escape from its enemies or to defend it self against
them. It is therefore but natural that under such circumstances it very easily dies iu the traps.
Even after the change of shell is over the Lobster remains weak for some time. It therefore
hides among the stones at the bottom of the sea, and remains there until the new shell has become
sufficiently hard and its strength has returned.

"The earliest changing of shell which I observed during my journey was in the first part of
July, near Tananger. I here had an opportunity of observing a Lobster engaged in this process.
It had just been taken out of a lobster-box, and could be haudled without offering the least resist-
ance. The shell on the back was burst in the middle, and the tail and the feet were nearly all out
of the old shell, while the largest claw ouly stuck out half its length. This latter portion of the
change of shell is evidently very dangerous, aud, although I observed it for quite a while, I could
see little or no progress. It is certainly a painful and dangerous process, and probably many a
Lobster loses its life at such times. Immediately after casting its shell the Lobster is lean and
miserable, aud only obtains its proper condition after the lapse of considerable time. According
to my observations, the change of shell takes place chiefly during the mouth of July. It certainly
happens that some change later, but by far the larger number appear to shed duriug that mouth."



794 NATUKAL HISTORY OF AQUATIC ANIMALS.

The following note regarding the shedding of the European Lobster, abstracted from a report
by a Danish naturalist,' goes to confirm our previous statement, that the females shed soon after
spawning :

" After the Lobster has emitted its roe, and the young have left the mother, she begins to
shed. She therefore goes to safe places, and does not seem to care much for food while the old
skin is being loosened ; the shell finally opens in the back, and the animal goes into the water
naked. It then looks as if it were covered with velvet, on account of the considerable formation
of cells which is going on all over its surface. These cells afterward grow hard through small
particles of lime and form the new shell. This shedding of the shell goes on from the middle of
July to September, but not at the same time all along the coast, being earlier in the southern and
later in the northern part. The Lobster thus gets sick, as it is called, toward the end of June
near Sogndal, and the export must then cease, as the mortality among them becomes too great,
while near Karmo it is still in a healthy condition till July 15. Farther north the shedding of
the shell begins still later, and Lobster may be caught all through July."

KATE OF GROWTH. Nothing is known regarding the rate of growth of the Lobster for any
extended period of time. Just how many years must elapse before it reaches a length of, say, ten
inches has never been determined, nor can we expect to solve this problem without a long series
of careful observations, which it seems almost impossible to make. It is well known that the
Lobster increases in size only when shedding. As the old shell is cast away the soft body rapidly
expands to a certain extent, and then soon becomes invested again with a new hard covering.
Knowing the frequency of the shedding periods, and the amount of expansion at each, we could
easily determine the age of Lobsters of all sizes; but these are the very data which are lacking.
It is probable that the rate of growth is not the same at all shedding periods, but is greater in the
younger stages than in the older. The early transformation from the embryo to the first perfect
lobster form are all accomplished during a single season by several meltings, but beyond this
period we know nothing accurately concerning the intervals between moltings, but in a medium-
sized Lobster they probably occur only once or twice a year.

We have collected from several sources a few data as to the amount of expansion at certain
stages of growth, and although we cannot vouch for their accuracy, they are probably not far
from correct. The measurements given are for the length of the entire body without the claws.
One Lobster eight inches long before shedding measured ten inches after shedding; another
measured ten inches before and twelve inches after shedding; a third ten and one-half inches
before and eleven and three-fourths inches after shedding ; and a fourth ten and one-half inches
before and twelve inches after shedding. If these measurements had all been taken with care
they would indicate that the rate of growth was not always the same in different individuals of
about the same size.

The lobster fishermen have very different notions regarding the ages of Lobsters, and while
some contend that they attain a marketable size in two or three years, others extend the period to
eight or ten years. The matter is one of considerable importance, bearing as it does upon the
framing of proper protective laws, and the feasibility of lobster culture and breeding.

Mr. Frank Buckland, in his report for 1877, gives the two following notes on the frequency
of shedding and the rate of growth of the European Lobster. They are not, however, very
satisfactory; aud we cannot believe that the American lobster sheds as frequently after the
first year or two.

" According to some careful observations made at the marine laboratory, Concarneau, it
1 AXIL BOBCK: Om det noreke Hummerfiskc og (lets Historic. Copenhagen, 18C8V69.



i;i:ri;oi>r(TioN OK TIIK mr.sn.i;.



appears that the th-t \i-arthe I.uhMer sheds his shell six times, the second year six times. I he
third year four times, ami tin- fourth \cai three times.

"The following table shows the rate of growth iu a Lobster after each shedding of its shell:



Shedding*


1 DCtfc


Wright.


Eighth


Incha.
3


OHM


DracAnu.
11

H

m

H

M

10J
4*


Ninth


H


3




Tenth




Eleventh _




Twelfth


Si

4
41




Thirteenth






i






BEPBODUCTION GENERAL REMARKS. Comparatively little has yet been made known
regarding the reproduction of the American Lobster and the habits of the female during the
spawning season. This is very unfortunate, considering the important bearing of all such
information upon the question of the artificial breeding of Lobsters, which, if it is feasible, may
ere long have to be undertaken iu order to replenish our already diminished supplies. Many
obstacles have been mentioned as standing in the way of such an enterprise, but from the
favorable beginnings already made in Europe, as well as in this country, we are inclined to
believe it will terminate successfully.

Most of our larger crustaceans, including the Lobster and common Crabs, although living
mainly upon the bottom when adult, have free-swimming young, which, as soon as they leave the
egg, and for a more or less prolonged period, lead a very erratic life. Not only, however, do the
habits of the young generally differ very widely from those of the adults, but the appearance and
structure of the two are as widely unlike. As described under "shedding," the Lobster grows
by a series of molt s. A molting or shedding of the skin indicates that the animal has grown
too large for its inelastic outer coat. Now, the very young, or the larva;, as they are sometimes
called, grow in the same manner as the adults. When the higher crustaceans first leave the eggs



Online LibraryG. Brown (George Brown) GoodeThe fisheries and fishery industries of the United States (Volume 1:1) → online text (page 131 of 146)