Herring Clupea harengus Linnaeus 1758

SEA HERRING; LABRADOR HERRING; SARDINE; SPERLING; BRIT

Description—

The sea herring is typical of its family in form, with body so flattened that it is much deeper than thick; moderately pointed nose; large mouth situated at the tip of the snout and lower jaw projecting a little beyond the upper when the mouth is closed; sharp-edged belly; and deeply forked tail. The dorsal fin stands over the much smaller ventrals, its origin about midway the length of the body. The scales are large, their rear margins rounded, and so loosely attached that they slip off at a touch. There is no adipose fin, and its absence at once distinguishes all the herrings from any of the salmon tribe. The chief anatomical character separating the sea herring from the shad and from the several alewives (genus Pomolobus) is that it has an oval patch of small teeth on the vomer bone in the center of the roof of the mouth. Conspicuous field marks separating herring from shad, hickory shad, and alewife are that the point of origin of its dorsal fin is about midway of the length of its trunk (considerably farther forward in the others); its body is not so deep, a difference shown better in the illustrations; and the sharp midline of its belly is only very weakly sawtoothed but is usually strongly so in the others, especially along the space between ventral and anal fins.

Color—

Deep steel blue or greenish blue on the back with green reflections; the sides and belly silvery; the change from dark belly to pale sides often marked by a greenish band. The gill covers sometimes glisten with a golden or brassy gloss; indeed, fish just out of the water are iridescent all over with different hues of blue, green, and violet; but these colors soon fade, leaving only the dark back and silvery sides. The ventral and anal fins are translucent white; the pectorals, however, are dark at the base and along the upper edge; the caudal and dorsal fins are dark grayish or shading into green or blue.

Size—

Herring grow to a length of about 17 inches and to a weight of about 11/2 pounds.

Habits—

The herring is a fish of open waters, [page 89] traveling as a rule in schools of hundreds or thousands; single fish are seldom seen, or even small companies of a few dozen. As a rule all the individual members of a school are about the same size, whether large or small. It is not known how long any given school may preserve its identity as such. Fridriksson and Aasen,^[21] it is true, found that herring tagged and released together might be recaptured from widely separated localities, suggesting that schools are more or less temporary formations. But this may not apply to schools that have assembled under natural conditions.

When a school is at the surface, as often happens on a calm day, its presence is betrayed by a fine rippling of the water, but we have never seen herring "finning" or lifting their noses above the surface as menhaden often do (p. 114). They come to the surface most often by night, when their presence is betrayed by their luminous trails, if the water is "firing," as we have often seen. A school is likely to be more or less stationary when feeding, its members swimming slowly to and fro and drifting as a whole with the current.^[22] But at other times schools are seen traveling with individual fish swimming side by side, rank below rank, as far down in the water as the eye can see from a boat, all heading in one direction apparently with some purposeful intent. We have often watched schools of "sardine" size streaming close past a certain rocky headland in the southern side of Massachusetts Bay, seemingly in unending procession.

As Dr. Huntsman points out, "There is no indication that herring swim against the current unless the water is somewhat turbulent."^[23] If they do so under such conditions, it depends on the relationship between their rate of swimming and the strength of the current whether they actually make headway against it or lose ground, tail first.

We might also add that schools of herring, like schools of menhaden, are not so easily frightened by the approach of a boat, as mackerel often are, and striped bass. Herring do not jump unless frightened. But the smaller sizes are often seen jumping when pursued from below by larger predatory fishes, such as silver hake or striped bass, a common spectacle. Fridriksson and Aasen found that herring, held in live-nets, swam constantly at a rate of about 0.2 to 0.25 sea miles per hour (6-8 meters per minute) when not disturbed. And it is certain that they are capable of long journeys, for a number of herring tagged on the northeast coast of Iceland have been recaught in southern Norway, and some vice-versa.^[24]

The activity of the herring is controlled in great part by the temperature of the water. In Passamaquoddy Bay, for example, they are "observed to move very sluggishly when the water is coldest in February and March,"^[25] and probably this applies all around the periphery of our Gulf, for the upper 20 fathoms ordinarily cools to about 33 to 36° F. during those months, with the surface often chilling to the freezing point of salt water in bays and harbors. The herring become active again when the water has warmed to about 40 to 43°.

Food—

The herring is a plankton feeder. When first hatched, and before the disappearance of the yolk sac, the larvae (European) feed on larval snails and crustaceans, on diatoms, and on peridinians, but they soon begin taking copepods, and depend exclusively on these for a time after they get to be 12 mm. long, especially on the little Pseudocalanus elongatus.^[26] As they grow older they feed more and more on the larger copepods and amphipods, pelagic shrimps, and decapod crustacean larvae. Examination of 1,500 stomachs^[27] showed that adult herring near Eastport were living solely on copepods and on pelagic euphausiid shrimps (Meganyctiphanes norwegica), fish less than 4 inches long depending on the former alone, while the larger herring were eating both.

When feeding on euphausiids, we have often seen them pursuing the individual shrimps, which frequently leap clear of the water in their efforts to escape. Even in winter, when shrimp are rarely seen at the surface, Moore found them an important article in the diet of the Eastport herring. And, it is likely that the local appearances [page 90] and disappearances of schools of large fish in the open Gulf are connected with the presence or absence of euphausiid shrimp of one species or another. A few of the larger fish, however, as well as the smaller ones, will usually be found full of copepods, even when both shrimp and copepods abound, and copepods are the chief dependence of all our herring, large and small, in the absence of shrimp. The amphipod genus Euthemisto also is an important food for herring in European seas; hence the absence of Euthemisto from the herring stomachs examined by Moore and by us has doubtless been due to the comparative scarcity of this large active crustacean in the coastwise waters of the Gulf of Maine.

The particular species of copepods on which Gulf of Maine and Woods Hole herring depend have not been identified, but we might guess that Calanus predominates, with Pseudocalanus, Acartia, and Centropages, and Temora also, at its times of abundance, while Euchaeta offers a rich food supply when the schools seek the deep waters of the basin frequented by these mammoth copepods.

In default of an abundant supply of Crustacea, and sometimes even when these are plentiful, herring feed on whatever molluscan larvae, fish eggs, Sagittae, pteropods, annelids that the water contains, even on microscopic objects as small as tintinnids and Halosphaera. But the smaller microscopic plants, either diatom or peridinian, are never found in the stomachs of herring more than 15 to 20 mm. long, probably because their gill rakers are not fine enough to retain them.

Although herring normally are not fish eaters, small launce, silversides, and the young of their own species have been found in them at Woods Hole. And Templeman^[28] reports them as consuming quantities of small capelin, in winter, in Newfoundland waters.

Herring ordinarily pick up their food objects individually by a "definite act of capture" as Battle expresses it,^[29] while she found that herring in the aquarium at St. Andrews did not feed in complete darkness, though they did in faint light. But it seems that when feeding on very small objects they may strain these out with their branchial sieves as the menhaden does (p. 114), for Moore, a very accurate observer, described them as swimming open mouthed when feeding on minute crustaceans, crossing and recrossing on their tracks.^[30]

Doubtless it is because of their feeding habits that herring seldom take a baited hook, if they ever do. But we think it likely that large ones when feeding on shrimp would take an artificial fly, as spent and hungry alewives will (p. 104) on their return to salt water, and as shad will on their way upstream (p. 109).

Enemies—

The herring is the best of all bait fishes in our Gulf, where it is preyed upon by all kinds of predaceous fish, especially by cod, pollock, haddock, silver hake, striped bass, mackerel, tuna, salmon, and dogfish, and by the mackerel sharks. Silver hake, in particular, often drive schools of herring up on our beaches, where pursued and pursuers alike strand on the shoaling bottom. We once saw this happen at Cohasset in Massachusetts Bay many years ago, on an October morning, when hake and herring were so intermingled in shallow water at the height of the carnage that we soon filled our dory with the two, with our bare hands. The finback whales also devour herring in great quantities. The shortfinned squid (Ilex) likewise destroys multitudes of the young sardines. On one occasion near Provincetown, in June 1925, we watched packs of perhaps 10 to 50 squids circling around a school of 2- to 4-inch herring, bunching them into a compact mass. Individual squids then darted in, seized one or two herring, ate only a small part, then darted back for more. A silvery streak of fragments of dead herring remaining along the beach bore witness to the carnage.

Breeding habits, development and growth—

Much attention has been devoted to the breeding habits and growth of the herring by European zoologists, by Moore, and by Huntsman in our own Gulf, and by Lea^[31] in more northern Canadian waters.

Herring may spawn in spring, in summer or autumn, according to locality, or both in spring and autumn (for further information on this matter, see p. 98). They do so chiefly on rocky, pebbly, or gravelly bottoms, on clay to some extent, probably never on soft mud. Spawning in the Gulf of Maine (including the Bay of Fundy), takes place chiefly from 2 or 3 fathoms down to about 30 fathoms; perhaps never in the littoral [page 91] zone, nor has herring spawn ever been reported as cast up by the surf on the beaches of New England, a fate that often overtakes it in the Gulf of St. Lawrence. Occasionally they spawn as deep as 100 fathoms in Scandanavian waters, perhaps also in the eastern basin of our Gulf where the sea floor is hard, not soft and muddy as it is in the basins in the western side. During the act of reproduction as observed by Moore at Cross Island and at Machias, Maine, "the fish were darting rapidly about, and those who have opportunity to see the fish spawning in more shallow water where observation is more favorable, state that both males and females are in constant motion, rubbing against one another and upon the bottom, apparently by pressure aiding in the discharge of the eggs and milt."^[32]

A female herring may deposit from 20,000 to upwards of 40,000 eggs, according to her age and size, averaging about 30,000. In sexually mature herrings, the genital organs are so large just before spawning commences that they make up about one-fifth the total weight of the fish.

The eggs sink to the bottom, where they stick in layers or clumps to the sand or clay, to seaweeds, or to stones, by means of their coating of mucus, or to any other objects on which they chance to settle. They are often found massed on net warps, anchors, and anchor ropes. The individual eggs are 1 to 1.4 mm. in diameter, depending on the size of the parent fish and also, perhaps, on the local race of fish involved. The period of incubation is governed by temperature; European students tell us that it requires as long as 40 days at 38-39°, 15 days at 44-46° and 11 days at 50-51° F.; while experiments on the Massachusetts coast by the U. S. Bureau of Fisheries gave 10 to 12 days in the temperature prevailing there in autumn. And MacFarland^[33] found that all of the eggs kept at Grand Manan at about 59° (15° C.) hatched, but that none hatched at 32-41° (0-5° C.), and that all died that were warmed to 68° (20° C.). Ten to fifteen days might be stated as an average incubation period for the Gulf of Maine, under existing temperatures.

The larvae of the herring family are very slender and can easily be distinguished from all other young Gulf of Maine fish of similar form (e. g., launce, smelt, or rock eel) by the location of the vent, which is so far back that it lies close to the base of the tail. But it requires critical examination to distinguish our several clupeoids one from another in their early stages.

The sea herring is about 5 to 6 mm. long at hatching, with a small yolk sac that is absorbed by the time a length of about 10 mm. is reached. The dorsal fin is formed at 15 to 17 mm.; the anal at about 30 mm.; the ventrals are visible and the tail well forked at 30 to 35 mm.; and at about 40 mm. (11/2 in.), the little fish begins to look like a herring.

According to Huntsman's observations, fry produced on the Grand Manan spawning grounds in late summer and early autumn grow to a length of 17 to 20 mm. by the end of November or first of December; they are 26 to 50 mm. (1-2 in.) long in March and April and 50 to 60 mm. (2-23/8 in.) long by June when fry of this size are abundant in the St. Andrews region. This is in line with our own observations that fry of 2 to 21/2 inches (50-65 mm.) predominate among the young herring at Provincetown at the end of June, and fry of 21/8 to 4 inches (54 to 100 mm.) on Nantucket [page 92] Shoals in mid-July. They grow to about 31/2 to near 5 inches (90-125 mm.) by the end of their first year of life; fish of that size, presumably of the previous autumn's hatch, are abundant in the fall in the Bay of Fundy, and at Boothbay, Maine. The growth rate is about the same at Woods Hole, where herring spawned in October and early November are 3 to 5 inches (76-125 mm.) long by the following autumn. The Norwegian herring, also, average about 5 inches (125 mm.) long at the end of their first year, according to Hjort, and North Sea herring are about 4 inches (100 mm.) long then.^[34]

Subsequent growth—

The herring has proved a particularly favorable object for growth studies based on the structure of the scales.^[35] Without pursuing this subject, which would lead us far afield, we may point out that herring not only grow at different rates at different times of year, with the contrast between the rapid growth of summer and the slow growth of the winter greater or less in different seas, but that they grow rapidly when young and slowly thereafter in some localities, whereas they may grow slowly at first in other localities, but sustain a more even growth to old age.

The Dogger Bank herring, for example, in the North Sea approximate 4 inches in length at the end of the first year, 81/2 to 9 inches at the end of the third year, 101/2 at the end of the sixth, and 111/2 to 12 inches at the end of the ninth, though with considerable variation. The Norwegian herring, however, spawned in the year 1899, averaged only 71/4 inches when 3 years old, but were as large as the Dogger Bank fish of equal ages by their sixth year and subsequently.^[36] Newfoundland herring grow more slowly at first than those in the southern side of the Gulf of St. Lawrence, but catch up with them as they grow older.

Huntsman credits the Bay of Fundy herring with about 10 inches at the end of their third year; i. e., when 4 years old, which agrees closely with an average growth of 97/8 inches at 4 years as calculated by Lea for Gulf of St. Lawrence fish. The average growth rate of the older Bay of Fundy fish probably falls between that of the Gulf of St. Lawrence fish and that of the herring of outer Nova Scotia which grow a little faster; i. e., to between 101/4 and 113/8 inches at 5 years; between 11 and 121/2 inches at 7 years; and between 121/2 and 131/8 inches at 9 years.^[37] Bay of Fundy herring make most of their growth from May to September. In the southern parts of our Gulf, where the growth period probably continues a month later into the fall, they may grow as fast as they do along outer Nova Scotia.

When the little herring have reached an age of about 2 years and a length of 71/2 to 8 inches (190-200 mm.) they accumulate large amounts of fat among the body tissues and viscera during the warm months of the year when growing rapidly, but lose this fat in winter and also at the approach of sexual maturity. We can bear witness and the fact is well known to fishermen that this "fat" stage is as characteristic of American waters as of European, where "fat" herring are the objects of extensive fisheries.

According to Moore, who examined thousands [page 93] of fish about Eastport, herring rarely spawn when less than 91/2 inches long; usually not until they are 10 to 101/2 inches; and most of the spawners are 12 to 13 inches long. This means that some few spawn when only 3 years old, if the growth schedule outlined above is correct, but most of them not until 4 years or older, to continue spawning annually thereafter as long as they live. In Norwegian waters, too, a few spawn at 3 years, many at 4 years, and the majority at 5 years; some few not until 6 years old. Herring have been seen as old as 20 years, and they may live even longer.

Success of reproduction—

The relative abundance of any species of sea fish from year to year depends less on how many individuals spawn in any locality than it does on how many of the resultant fry survive. And the many age analyses that have been made of herring in European waters have proved that while a very large crop of young may be produced in some years, hardly any are in others, even in favorable nurseries. Apparently this applies more to the northern breeding grounds than to the southern (to some extent, however, to all) the result being that the herring spawned in some one favorable breeding season may dominate the schools over large areas for many years, or until another successful breeding year comes, producing another large crop. In Norwegian waters, for example, the herring produced in 1904 was dominant in the catches for the next six years, at least; this is a classic instance. Lea found, similarly, that herring hatched that same year (1904) dominated the catches on the west coast of Newfoundland as long afterwards as 1914 and 1915. And while precise information is not available for our Gulf, no doubt the same rule governs there.

One case, at least, is well documented of a particular body of Bay of Fundy herring that received no important recruitment for something like 10 years, when the few still remaining seem to have disappeared, from old age (p. 99).

Various explanations have been proposed to account for this, such as abundance or scarcity of microscopic plankton, favorable or unfavorable temperature, salinity, or other factors, all of which may enter in. And while it is during the first few weeks of life that the herring is most vulnerable, it is also possible that the conditions under which the parent fish lived for the year preceding spawning may influence the fate of the fry. Whatever the explanation, the fact that such fluctuations do occur from year to year, in the numbers of fry reared is of the greatest practical interest to all concerned with the sea fisheries, as evidence that variations existing in the stock of herring, and consequently in the catch, may be due more to the success or failure of reproduction than to any effect the fishery may have on the stock.

General range—

Both sides of the North Atlantic. Off the European coast the herring ranges north to Norway, Iceland, Spitzbergen, and the White Sea; south to the Straits of Gibraltar. It is known on the American coast as far north as northern Labrador and the west coast of Greenland; regularly and commonly as far south as Cape Cod and Block Island; and it is occasionally seen in small numbers as far south as Cape Hatteras in winter. It is replaced by a close ally (C. pallasii) in the North Pacific.

Occurrence in the Gulf of Maine—

To list the localities where herring have been recorded would be to mention every hamlet along our coasts whence fishing boats put out, for more or less herring, large or small, appear at one season or another around the entire coast line of the Gulf, and on the offshore fishing banks as well. They also enter bays and estuaries freely, but they have never been reported in our Gulf from water that is appreciably brackish; perhaps 2.8 percent salinity^[38] may be set at about their lower limit.

The distribution of commercial catches, plotted by Needler (fig. 44)^[39] shows that herring are far more plentiful from Casco Bay eastward along the coast of Maine, and especially in the Passamaquoddy Bay-Grand Manan region than they are along the western shores of the Gulf on the one hand, or up the Bay of Fundy on the other, or along western Nova Scotia. Thus the landings per unit length of coast averaged 3 times as great for the Passamaquoddy-Grand Manan region and for the coast of Maine to Mount Desert, as for the coast sector from Mount Desert past Penobscot Bay; about 4 times as great as for the Maine coast as a whole, westward and southward [page 94] from Penobscot Bay; and 13 times as great as for the coast of Massachusetts,^[40] for the years 1919, 1928, 1929, and 1930.^[41]

Present day landings of upwards of 30 million pounds of sardines alone, for Charlotte County, New Brunswick, even in poor years, up to something like 100 million pounds in good years, plus some 9-14 million pounds of larger herring, contrasted with a maximum of only about 17 to 18 million pounds reported for 1947 for any sector of the Maine coast of comparable length,^[42] show that the Passamaquoddy-Grand Manan region has not lost its preeminence as a herring center. The abundance of little herring there is, in fact, the outstanding feature of the distribution of fishes in the Gulf of Maine. A catch of about 2,400,000 pounds for Massachusetts in 1947, contrasted with some 11,300,000 pounds for the Penobscot Bay region alone in that year, illustrates how much less rich in herring the southwestern side coast line of the Gulf is than the sector that happens to be the least productive part of the northern coast line of the Gulf.

Fishermen tell us, too, that herring are much more regular in their occurrence from year to year in the Passamaquoddy-Grand Manan region than they are either off western Nova Scotia in the one direction, or along the coast of Maine in the other. And this is borne out by such statistics as are conveniently available. Thus only one-fourth to one-fifth as many pounds of herring were caught in the Penobscot Bay region^[43] in 1947 as either eastward [page 95] to Lubec Narrows on the one hand, or westward past Casco Bay to Cape Elizabeth on the other,^[44] whereas the catches for 1919 were rather evenly distributed along the northern and eastern Maine coast as a whole.

We find herring even more and more sporadic in their appearances and disappearances, both from place to place, from week to week, and from year to year, passing southward around the western periphery of the Gulf. Very few, for example, are seen on the southern side of Massachusetts Bay in some years (as in 1950 and 1951); many schools in others. And herring are such wandering fish in general, here today and gone tomorrow even in their centers of abundance, that the successful location of the weirs depends largely on intimate local knowledge and on close observation of the movements of the schools.

Herring appear, also, to be far less plentiful on the offshore banks and less regular in their occurrences there than they are in their inshore center of abundance in the northeastern part of the Gulf. Trawlers, it is true, occasionally pick up schools on Georges Bank and on Browns Bank, as in 1931, when catches of 3,000 pounds were reported on the northern edge of Georges and of 2,800 pounds on the southwestern part in October. Schools, too, are occasionally reported as seen at the surface, by Albatross III for instance, in April-May 1950. Fishermen used sometimes to set drift-nets on Georges for herring for bait in the days of the long line fishery, and small numbers up to 130-160 per haul, were trawled by Albatross III, widespread on the western part in depths of 20 to 50 fathoms in May 1950, as well as off southern New England.^[45] But it is more usual for trawlers operating on Georges to pick up only odd fish or none. Thus the maximum catch on any trip during the otter trawl investigation of 1913 was only a dozen or two; 42 hauls by the Eugene H, in late June 1951, yielded only one herring, fishing from Nantucket Lightship out onto the south-central part of Georges; and the stomachs of cod caught on Georges seldom contain herring, if they ever do.^[46]

The appearance of schools of large herring or of small is distinctly a seasonal event off most parts of our coast, and the picture is made still more complex by differences in the behavior of sardine-size, "fat," and spawning herring, the reasons for which are not yet well understood.

The newly spawned fry, less than 3/4 of an inch (9-11 mm.) long, have been taken in September in the lower part of the Bay of Fundy, a product, doubtless, of the Grand Manan and West Nova Scotia spawning; also in October in Gloucester Harbor where one tow-net haul yielded us a great number on the 24th, in 1916. And they are to be expected wherever herring spawn in numbers in any particular year. It seems likely that most of them remain near their birth place during their first autumn and winter, when the circulation of the Gulf is in its least active stage. But they become widely distributed during the spring (March-May), when 11/2 to 2 inches (30-50 mm.) long, both in the lower Bay of Fundy, around the entire periphery of the open Gulf, east as well as west, out over the basin, and on the northern and eastern parts of Georges Bank.^[47]

Little seems to be known in detail about the movements of herring during their first year, but those that find their way into enclosed waters where mid-summer temperatures are high, such as Duxbury and Plymouth Bays and Provincetown Harbor, appear to move out during the early part of the summer, being reported as far less plentiful there in June than they are in April and May. Sardine-size herring, 4 to 8 inches long including 1- and 2-year-olds, are to be expected in abundance all summer east of Penobscot Bay, and particularly in the Passamaquoddy Bay region, where they support the sardine fishery for which the latter is famous, and where they are present throughout the year.

It is probable, however, though not proved, that the 1- to 2-year-olds (fish in their second and third years) do not appear along the southwestern coasts of the Gulf until several months later in the season than the little fish of 1/2 to 2 inches do, that were hatched the preceding autumn. Thus it usually is not until late June, July, or August that "sperling" of 4 to 7 inches are reported in numbers off the Massachusetts coast, or that we [page 96] have seen them there. They are even more erratic, too, in their appearances and disappearances in Massachusetts Bay and along Cape Cod than they are to the eastward of Mount Desert. At Cohasset, for example, on the southern shore of the Bay where we have had many years' experience, schools of sperling are here today in summer and early autumn, but gone tomorrow. It is also our impression that the sperling, like the larger herring, are not only far less concentrated in favorable localities around the southwestern shore of the Gulf than they are to the north and east, but far less numerous on the whole.^[48]

These first two year classes (the fish in their first year having grown to a length of 3 or 4 inches by September; those in their second year to 7 to 9 inches) begin to thin out from the shore waters of the open Gulf after the middle of October as the water cools, and few "sardines" are taken there after early December.

The corresponding ebb and flow, so to speak, for the sardine is suggested in a striking way by the average monthly catches of sardines by the weirs in Charlotte Co., New Brunswick (Passamaquoddy Bay, Campobello, and Grand Manan) for the year 1920, which are equally illustrative of conditions today:

Here, however, the seasonal variation (as Dr. Huntsman informs us) is simply a matter of local availability, for sardines remain in Passamaquoddy Bay all winter, but do not move about much then. Probably the sardines winter mostly on the bottom. And there is no reason to suppose that the bulk of them travel far in any part of the Gulf.

Very little is known about the Gulf of Maine herring during their third summer, when they have passed the "sardine" or sperling stage and have not yet reached spawning age. In some years these "fat" herring, as they are often called, or "summer" herring, weighing up to about one pound (they are called "spawn" herring locally, but this is an error), are taken in the traps at Provincetown for a week or so about mid-April; they are taken at about the same time off Gloucester (in 1915 they were reported 8 to 15 miles off Cape Ann on the 17th), and they are said by the fishermen to "show" first off Seguin Island in May and June, off Mount Desert late in summer. Doubtless they form a large part (just what proportion is not known) of the catches of herring larger than sardines that are made in the Passamaquoddy Bay region, also around Grand Manan. As a rule few of them are taken inside the inner islands elsewhere, though they came into the harbor of Boothbay about May 14 in 1914.

When a mackerel seiner picks up a school of herring out in the open Gulf in summer,^[49] or when an otter trawler makes a catch of herring on Georges Bank (p. 95), most of them are very fat and show no signs of approaching sexual maturity. Thus it seems that they tend to keep farther offshore than do either the younger herring or the still older mature herring.

The peak season for herring larger than "sardines" inshore in the northeastern part of the Gulf is ordinarily from July through October; i. e., some 2 months less than that for the sardines (see p. 96). But a greater proportion of the larger fish continue available there through the cold months than of the younger fish, to judge from the fact that considerably larger catches are made of big herring in winter than of sardines, whereas the total local catch is much larger for the latter than for the former.

A report^[50] on the average monthly landings of large herring for Charlotte County, for the period 1920-1931, to the nearest 1,000 pounds, follows:

[page 97]

Large herring (Dr. Huntsman tells us) are also present there throughout late winter and spring, though few find their way then into the weirs.

In the southeastern part of the Gulf, as typified by Cape Cod Bay, large herring appear inshore in greatest numbers to about June and again in the autumn, with very few (and not many sardines) in June or July. This is illustrated by the largest and smallest catches made in 8 traps at North Truro for different months during the years 1946 to 1952. The following data are contributed by the Pond Village Cold Storage Company:

The earliest catch of sardines there in those years, or in 1935, 1938, or 1943 was sometime in May, the latest November 16 to 17; the earliest catch of large herring was made between April 20 and 30, the latest on December 10th.

In most years the large herring vanish from the Massachusetts coast at some time in December. In 1950, for example, they vanished about December 4th from Ipswich Bay, where considerable catches had been made for some time previous by about 15 boats.^[51]

Nothing is known, definitely, as to their seasonal appearances and disappearances over the offshore banks.

About all that is known of the movements of the large mature herring (in their fourth summer and older) is that they are encountered in numbers only for the brief period before, during, and after the spawning season, when they are seen schooling at the surface, and are caught along shore. Fishermen report that they show about the off-lying islands some time before they make their way up the bays; two or three weeks earlier, for instance, at Grand Manan, Jonesport, and about Mount Desert Island than within Machias Bay. They are said to appear some time after the middle of July at Isle au Haut at the eastern entrance of Penobscot Bay, and at Castine within the Bay, though not until the end of that month or the first of August at Matinicus Island. Such of them as visit the Massachusetts Bay region are not expected there until the last week in September. But they are in full force on all the spawning areas along the shores of the Gulf by October, from Grand Manan to Cape Cod; they are equally widespread, if less abundant, inshore in November, and they are reported in December occasionally, and even later. It is probable that as the fish spawn out most of them move out promptly from the spawning grounds into deeper water, for fish recently spent are not often reported as taken in the weirs.

Probably the spawners merely descend into deeper water to winter, as is the case in European waters. How deep the great body of them go is not known. But is has been proved that herring of all ages remain in the open Bay of Fundy throughout the cold season; also in the passages between the inner and outer divisions of Passamaquoddy Bay, even when water temperatures there are as low as 32° F.^[52] And the abundance of pelagic euphausiid shrimps (a favorite herring food) in the deeper water layers of the northeast corner of the Gulf suggests this as a rich winter pasture for them.

Studies carried out from the Atlantic Biological Station at St. Andrews, chiefly under Dr. A. G. Huntsman's^[53] leadership, and by the International Passamaquoddy Fisheries Commission^[54] during the early 1930's seem to us to have proved that the factor chiefly responsible for the great concentration of young herring in the Passamaquoddy region, and for their availability to the weir fishery there, is the differential circulation of the shoaler and deeper water layers that is set in motion by the inflow of fresh water from the tributary streams combined with superficial currents set up temporarily by the wind. In other words, the sardine-sized herring acts as does any planktonic animal such as the euphausiid shrimps and the copepod crustaceans, on which it feeds, as it swims to and fro, i. e., it drifts with the current. In technical language, it is "denatant."

The case is not so clear for the larger herring, not because there is any reason to suppose they can direct their journeys more intelligently, and because any directive swimming they may carry [page 98] out is far more effective because it is more rapid; but because so little is known as to journeys any individual school actually makes as season follows season, whether of fat herring or of spawners. Perhaps the most interesting question of all, and one as yet unsolved, is how and why the spawning fish seek their spawning grounds year after year, when their sex organs mature.

Spawning grounds and season—

It appears that the most productive spawning ground for our Gulf formerly was and still is at the mouth of the Bay of Fundy, particularly on the shoals southwest of Grand Manan. The Trinity Ledges off western Nova Scotia are another important ground; and herring are reported as spawning commonly, though irregularly, in Machias Bay; about Jonesport; at Mount Desert; in Frenchmans Bay; among the islands at the mouth of Penobscot Bay (Swans, Isle au Haut, and Matinicus); in Casco Bay; also about Wood Island a few miles south of Cape Elizabeth, which has long been known as the resort of breeding schools. Herring have also been found spawning off the beaches along the western shore of the Gulf, Ipswich Bay, for example; about Cape Ann; in Massachusetts Bay; about Provincetown; along outer Cape Cod; in the Woods Hole region; near No Mans Land; and about Block Island which is the southern breeding limit. But whatever spawning does take place either southward from the vicinity of Cape Elizabeth on the one hand, or in the inner parts of the Bay of Fundy on the other, is trifling as compared with the production along the eastern coast of Maine and in the Grand Manan region.

Spawning takes place both along shore in our Gulf and on the various shoals and ledges that lie for 5 to 25 miles off the coast, a habit betrayed by the eggs that are found sticking to the anchor ropes of fishing vessels. But we find no definite record of herring spawning on Browns or Georges Banks, nor are young fry known there, a fact that was commented upon by Storer long ago.

Spawning season—

Both spring-spawning schools and summer-fall spawning schools of herring were reported formerly, in the Bay of Fundy, the spring spawners visiting the south (Nova Scotia) side of the bay from Bier Island at the mouth in as far as Digby Gut, also the Parrsboro region on the New Brunswick shore near the head of the bay, spawning during April and May. But they seem never to have been very numerous, and it is not known whether any spawn now in the bay before summer. Spring-spawning as well as autumn-spawning herring have also been reported to us by fishermen along the west coast of Nova Scotia, though we have not been able to verify this. Other than this, spring spawners are neither recorded nor rumored anywhere in the Gulf of Maine.

Around Grand Manan and in Machias Bay nearby, the heaviest runs of summer-autumn spawners usually come in July, August, and September, the spawning season continuing until late in the fall in some years,^[55] but not commencing until early August, and ending by early October in others.^[56] Passing westward we find the breeding period progressively later and shorter; mid-August for example until October around Petit Manan and near Mount Desert, while the few herring that spawn farther south do so chiefly during October in Ipswich^[57] and Massachusetts Bays; in late October and early November in the vicinity of Woods Hole.

So many observations have been taken in the Gulf from the vessels of the Bureau of Fisheries, and in the Bay of Fundy by the Biological Board of Canada, that it is possible to establish the temperatures rather closely at which herring spawn in our waters. Around Grand Manan and in the northern part of the Gulf generally, practically all spawning is carried out in water of about 46-52° F. But such herring as spawn in the southern part of Massachusetts Bay and along the shores of Cape Cod, where autumnal cooling of the surface waters is not so rapid as it is farther north, may do so in slightly warmer water, say up to 53° or 55°. The Gulf of Maine herring spawn in rather low salinities (such characterize the coastal zone as a whole as compared with the North and Norwegian Seas), the most saline water in which it is known to spawn within our limits being not saltier than 33 per mille, the freshest probably about 31.9 per mille. They never spawn in brackish water within the limits of the Gulf, although known to do so at the mouths of certain European rivers in water that is nearly fresh.

Destruction by natural causes—

The herring is a very "tender" fish, prone to wholesale destruction [page 99] both by stranding on beaches during storms, and by pollution of the water. Many instances of this kind have been reported. Allen,^[58] for example, saw young herring in windrows for miles on the strand at Rye Beach, N. H., in August 1911. A slaughter of herring (still more instructive because the exact course of events was followed) took place at Cohasset, on the south shore of Massachusetts Bay, in October 1920, On the 5th of that month a large school of "sperling," 4 to 5 inches in length, ran up the harbor (which is nearly landlocked), probably driven in by silver hake (at least so local fishermen said); were trapped there by the falling tide, and stranded on the mud. So numerous were they that the flats were entirely covered with them and it was estimated that 20,000 barrels of fish perished. During the next few days the fish (alternately covered and uncovered by the tide) decayed, and despite the tidal circulation, so fouled the water that lobsters impounded in floating cars died. On the 10th there was a second smaller run of herring, and on the 15th a third run came as numerous as the first, the newcomers dying soon after they entered the harbor. Altogether, it was estimated that 50,000 barrels of fish perished, of which more than 90 percent were "sperling," 5 to 10 percent were large adults, and a few were small mackerel and silver hake, besides large numbers of smelt. The flats were silvery with herring scales at low tide by the last half of October, when we saw them, and the residents about the harbor found the stench almost unbearable. But the fish decomposed and the water purified itself during the winter months.

Mass destructions of young herring have also been reported in other Gulf of Maine harbors. Thus, Dr. Austin H. Clark reported that early in August 1925 the mud flats in Manchester Harbor, on the north side of Massachusetts Bay, were white with stranded herring 3 to 5 inches long, packed several deep at low tide along the sides of the little drains and hollows. Another such destruction took place in the same harbor in the summer of 1928. Vast quantities of herring spawn are likewise cast up on the beaches every year to perish in north European waters; this also happens to some extent in the Gulf of St. Lawrence.

Numerical abundance and importance—

Moore (1898), who sifted many sources of information concluded (we believe rightly) that no general decrease had taken place in the abundance of young herring at the mouth of the Bay of Fundy up to that time. But it is common knowledge among fishermen that both the numbers visiting any given locality on our coast and the duration of their stay varies widely, not only from year to year, but over longer periods. Local spawning grounds, too, may be abandoned for a term of years—a common occurrence.^[59]

The best documented case of local disappearances from a previously productive ground took place, as Dr. Huntsman writes us,^[60] from the shoals southwest of Grand Manan, whence large herring (previously very plentiful) withdrew in 1877, to reappear in 1881 on the Nova Scotia coast between Cape Sable and Digby. Dr. Huntsman has suggested that they had circled the Gulf offshore, for their exodus from the Grand Manan shoals was not accompanied by any coincident increase in the catch along the eastern part of the coast of Maine, but rather by the reverse.^[61] They persisted on the Nova Scotia shore until 1890, when they gave out, probably from old age, for the large herring that remained in the Quoddy region also dwindled in numbers as shown by the collapse of the winter fishery there, evidence that this particular body of herring did not receive any significant recruitment after about 1880-1881. It remains to be seen whether large herring will ever reappear in their former plenty on the Grand Manan ground, as they did about 1857 in Massachusetts Bay, where the stock had been at a low ebb since 1837; or whether the yearly drain on the population of young herring by the sardine fishery (well started by about 1880) is too great.

The largest reported catch of herring for the Gulf as a whole for any year since 1928 for which statistics are readily available was 219,131,500 pounds taken in 1946, divided as follows: Massachusetts, 2,049,000 pounds; Maine, 80,107,400 pounds; and the Canadian shores of the Gulf, 136,975,100 pounds. The smallest catch was 70,519,886 pounds in 1932, divided 5,687,254 pounds, 31,988,132 pounds, and 32,844,500 pounds, [page 100] respectively. In 1947, incidentally, the herring catch of the Gulf was topped only by the catches of haddock and of rosefish.

It is not clear to what extent this range in the catch from year to year is due to fluctuations in the supply of fish; to differences in their availability; or to the sundry economic factors that enter in. What is certain is that with some 80 percent of the catch consisting of sardine-sized fish weighing only about one-half ounce, the toll taken cannot have been less than 11/2 billion fish in the poorest of recent years, 5 to 6 billion in the year when the yield was greatest, i. e., numbers far greater than that for any other Gulf of Maine fish. Come good year then or bad, Capt. John Smith's account of the herring of our Gulf thus applies equally well today: "The savages compare the store in the sea with the hair of their heads, and surely there are an incredible abundance upon this coast."^[62]

The sardine catch of the Bay of Fundy is made almost wholly in weirs, 347 of which were operated on the New Brunswick shore in 1947. On the Maine coast, as a whole, a little less than two-thirds the catch of herring, large and small, is made in weirs and in purse seines, combined, a little more than one-third nowadays in stop seines (about 44,500,000 pounds in 1947). These are used "to prevent the exit of the herring school from a cove or inlet. . . . The seine is stretched around the school with the ends of the net made fast to the shore." And stop seines are used mostly at night, when the presence of fish is betrayed by their luminous trails, if the water is firing, or by the noise they make as they "flip" at the surface.^[63] And some are still caught in floating traps (about 2 million pounds in 1947) which we have often seen used in the harbors of Mount Desert.

In 1947, seemingly a representative year, purse seines yielded the Maine fishermen nearly as much herring (about 36,100,000 pounds) as the weirs. Their presence is detected, Scattergood tells us, either by the firing of the water if by night, by echo sounding apparatus, or by the use of a thin wire suspended in the water, the vibrations of which indicate the presence of fish that strike it. In 1947 eleven purse seiners were active in the fall fishery for Maine herring. How many were engaged in the New Brunswick and Maine winter fishery is not known.

Large catches of herring when on bottom also are made by special otter trawls in European waters; and of the closely allied herring of British Columbia of late. But the possibility of developing an otter-trawl fishery for herring in the Gulf of Maine has not yet been explored.

Finally, we may remark that herring fresh from the water are among the most delicious of our fishes, especially the small sizes. Their only drawback is that they do not keep well, being richmeated and oily, and in the larger sized fish the many hair-like bones are troublesome.