FISHES of the herring family are amongst the most important economically in the oceans. Not only are they heavily exploited by man for food, but the immensity of their numbers make them an important food item for larger food fishes, as well as for a host of other marine life. In the north-eastern Atlantic extremely valuable commercial fisheries are based on three familiar members of the family, the herring, sprat, and the pilchard or sardine, while the anchovy fisheries of the Mediterranean are directed to catching a fourth species. In addition, the anadromous shads were once fished for in most European countries, although their present scarcity, which is probably as much due to overfishing as to the destruction of their spawning grounds, renders them now of little value. The immense shoals of young clupeoid fishes in inshore waters are also fished for as a source of fishmeal to say nothing of that highly priced delicacy, whitebait.
All the clupeoids are pelagic fishes, notable for the vast shoals which they form and also for the periodic wanderings that bring them in incredible numbers to their spawning grounds. All have relatively high fat content to their flesh, and are rather delicate fragile fishes. Their bodies are completely covered in scales, with the exception of the head; there is no lateral line, although there is a network of sensory canals on the head immediately underlying the surface skin. There is a single, dorsal fin usually placed near the mid-point of the body.
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A. Snout not prominent and sharply pointed, jaws approximately equal; mouth moderate, jaws never extend to behind the level of the eye. B
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AA. Snout prominent, sharply pointed; jaws large, extending well past the level of the eye; underside of body rounded; silvery flanks sharply distinct from dark green colour of back. Grows to 8 in (20 cm). North to the Channel and North Sea.
Anchovy Engraulis encrasicolus
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B. A distinct notch in the mid-line of the upper jaw; gill cover has distinct radiating ridges.
Shads C
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BB. No distinct notch in the mid-line of the upper jaw, gill cover has no radiating ridges (except in the pilchard). D
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C. Eighty or more gill rakers on the first gill arch (Fig. 49); a black spot at the edge of the gill cover, occasionally followed by only one or two other rounded black spots.
Grows to 24 in (60 cm). North to the northern North Sea. Uncommon.
Allis Shad Alosa alosa
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CC. Normally forty to sixty gill rakers on the first gill arch (Fig. 50); a black spot on the gill cover followed by a row of six or seven smaller rounded black spots along the sides. Grows to 20 in (50 cm). North to Iceland. Common.
Twaite Shad Alosa fallax
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D. Body flattened laterally with a pronounced keel along the belly, sometimes with sharply pointed scales; dorsal fin origin equidistant from snout and tail fin, and either above
or behind the pelvic fin origin; no pronounced ridges on the gill cover. E
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DD. Body oval in cross-section, no keel along belly; dorsal fin origin well in front of pelvic fin origin, and much closer to the snout than the tail fin; last ray of anal fin longer and wider than other rays; strong radiating lines on the gill cover. Grows to 10 in (25 cm). North to central North Sea.
Pilchard or Sardine Sardina pilchardus
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E. Belly has a sharp keel consisting of backwardly pointed toothed scales; twenty-one to twenty-three between the throat and pelvic origin, eleven to twelve from pelvic fins to vent; dorsal fin origin behind the origin of the pelvic fins; back greenish coloured when fresh. Grows to 5½ in (14 cm). North to Norway.
Sprat Sprattus sprattus
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EE. Belly has a weak keel; the scales not pro-nouncedly spiny when a finger is run from vent to head; twenty-seven to thirty scales on belly from throat to pelvic fins, thirteen to fifteen from pelvics to vent; dorsal fin origin above or slightly in front of the pelvic fin origin; back bluish in colour. Grows to 16 in (40 cm). From the Channel northwards.
Herring Clupea harengus
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