90 



FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



ances 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 com- 

 parative 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, Acar- 

 tia, 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 then- 

 own species have been found in them at Woods 

 Hole. And Templeman 28 reports them as con- 

 suming 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 liglil. 

 But it seems that when feeding on very small 

 objects they may strain these out with their 

 branchial sieves as the manhaden does (p. 114), for 

 Moore, a very accurate observer, described them 

 as swimming open mouthed when feeding on 



" Bull. Newfoundland Government Lab., No. 17, 1948, p. 133. 

 " Ann. Rept. Biol. Board Canada (1933), 1934, p. 14-15. 



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, mack- 

 erel, tuna, salmon, and dogfish, and by the mack- 

 erel 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 inter- 

 mingled in shallow water at the height of the car- 

 nage that we soon filled our dory with the two, 

 with our bare hands. The finback whales also 

 devour herring in great quantities. The short- 

 finned 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 groxoth. — 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 ex- 

 tent, 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 



»° Rept. U. S. Comm. Fish. (1896), 189S, p. 402. 

 » Age and growth of the herrings in Canadian waters. 

 1911-15 (1919), pp. 75-164. 



Oanad. Fish. Exped., 



