Herring

Video loop of a school of Atlantic herring migrating to their spawning grounds in the Baltic Sea

Herring are forage fish, mostly belonging to the family Clupeidae. They often move in large schools around fishing banks and near the coast. The most abundant and commercially important species belong to the genus Clupea, found particularly in shallow, temperate waters of the North Pacific and the North Atlantic oceans, including the Baltic Sea, as well as off the west coast of South America. Three species of Clupea are recognized, and provide about 90% of all herrings captured in fisheries. Most abundant of all is the Atlantic herring, providing over half of all herring capture.

Herring played a pivotal role in the history of marine fisheries in Europe,^[1] and early in the twentieth century their study was fundamental to evolution of fisheries science.^[2][3] These oily fish^[4] also have a long history as an important food fish, and are often salted, smoked, or pickled.

Species[link]

A number of different species, most belonging to the family Clupeidae, are commonly referred to as herrings. The origins of the term herring is somewhat unclear, though it may derive from the Old High German heri meaning a "host, multitude", in reference to the large schools they form.^[5]

The type genus of the herring family Clupeidae is Clupea.^[3] Clupea contains three species: the Atlantic herring (the type species) found in the north Atlantic, the Pacific herring found in the north Pacific, and the Araucanian herring found off the coast of Chile. Subspecific divisions have been suggested for both the Atlantic and Pacific herrings, but their biological basis remain unclear.

This article is one of a series on
Commercial fish
Large pelagic
billfish, bonito mackerel, salmon shark, tuna
Forage
anchovy, herring menhaden, sardine shad, sprat
Demersal
cod, eel, flatfish pollock, ray
Mixed
carp

Herrings in the genus Clupea
Common name	Scientific name	Maximum length	Common length	Maximum weight	Maximum age	Trophic level	Fish Base	FAO	ITIS	IUCN status
Araucanian herring	Clupea bentincki Norman, 1936	28.4 cm	cm	kg	years	2.69	[6]	[7]	[8]	Not assessed
Atlantic herring	Clupea harengus Linnaeus, 1758	45.0 cm	30.0 cm	1.05 kg	22 years	3.23	[9]	[10]	[11]	Least concern[12]
Pacific herring	Clupea pallasii Valenciennes, 1847	46.0 cm	25.0 cm		19 years	3.15	[13]	[14]	[15]	Not assessed

In addition, a number of related species, all in the family Clupeidae, are commonly referred to as herrings. The table immediately below includes those members of the Clupeidae family referred to by FishBase as herrings which have been assessed by the International Union for Conservation of Nature.

Other herrings in the family Clupeidae
Group	Common name	Scientific name	Maximum length	Common length	Maximum weight	Maximum age	Trophic level	Fish Base	FAO	ITIS	IUCN status
Freshwater herrings	Toothed river herring	Clupeoides papuensis (Ramsay & Ogilby, 1886)	cm	cm	kg	years		[16]		[17]	Data deficient[18]
Round herrings	Day's round herring	Dayella malabarica (Day, 1873)	cm	cm	kg	years		[19]		[20]	Least concern[21]
	Dwarf round herring	Jenkinsia lamprotaenia (Gosse, 1851)	cm	cm	kg	years		[22]		[23]	Least concern[24]
	Gilchrist's round herring	Gilchristella aestuaria (Gilchrist, 1913	cm	cm	kg	years		[25]		[26]	Least concern[27]
	Little-eye round herring	Jenkinsia majua Whitehead, 1963	cm	cm	kg	years		[28]		[29]	Least concern[30]
	Red-eye round herring	Etrumeus teres (De Kay, 1842)	33 cm	25 cm	kg	years		[31]	[32]	[33]	Not assessed
	Two-finned round herring	Spratellomorpha bianalis (Bertin, 1940)	4.5 cm	cm	kg	years	3.11	[34]		[35]	Data deficient[36]
	Whitehead's round herring	Etrumeus whiteheadi (Wongratana, 1983)	20 cm	cm	kg	years	3.4	[37]	[38]	[39]	Least concern[40]
	Venezuelan herring	Jenkinsia parvula Cervigón and Velasquez, 1978	cm	cm	kg	years		[41]		[42]	Vulnerable[43]
Thread herrings	Galapagos thread herring	Opisthonema berlangai (Günther, 1867)	26 cm	18 cm	kg	years	3.27	[44]		[45]	Vulnerable[46]
	Middling thread herring	Opisthonema medirastre Berry & Barrett, 1963	cm	cm	kg	years		[47]		[48]	Least concern[49]
	Pacific thread herring	Opisthonema libertate (Günther, 1867)	30 cm	22 cm	kg	years		[50]	[51]	[52]	Least concern[53]
	Slender thread herring	Opisthonema bulleri (Regan, 1904)	cm	cm	kg	years		[54]		[55]	Least concern[56]
Other	Blackstripe herring	Lile nigrofasciata Castro-Aguirre Ruiz-Campos and Balart, 2002	cm	cm	kg	years		[57]		[58]	Least concern[59]
	Denticle herring	Denticeps clupeoides Clausen, 1959	cm	cm	kg	years		[60]		[61]	Vulnerable[62]
	Dogtooth herring	Chirocentrodon bleekerianus (Poey, 1867)	cm	cm	kg	years		[63]		[64]	Least concern[65]
	Graceful herring	Lile gracilis Castro-Aguirre and Vivero, 1990	cm	cm	kg	years		[66]		[67]	Least concern[68]
	Pacific Flatiron herring	Harengula thrissina (Jordan and Gilbert, 1882)	cm	cm	kg	years		[69]		[70]	Least concern[71]
	Sanaga pygmy herring	Thrattidion noctivagus Roberts, 1972	cm	cm	kg	years		[72]		[73]	Least concern[74]
	Silver-stripe round herring	Spratelloides gracilis (Temminck & Schlegel, 1846)	10.5 cm	cm	kg	years	3.0	[75]		[76]	Not assessed
	Striped herring	Lile stolifera (Jordan & Gilbert, 1882)	cm	cm	kg	years		[77]		[78]	Least concern[79]
	West African pygmy herring	Sierrathrissa leonensis Thys van den Audenaerde, 1969	cm	cm	kg	years		[80]		[81]	Least concern[82]

There are also a number of other species called herrings, which may be related to clupeids or just share some characteristics of herrings (such as the lake herring, which is a salmonid). Just which of these species are called herrings can vary with locality, so what might be called a herring in one locality might be called something else in another locality. Some examples:

Other fishes called herring
	Common name	Scientific name	Maximum length	Common length	Maximum weight	Maximum age	Trophic level	Fish Base	FAO	ITIS	IUCN status
Longfin herring	Bigeyed longfin herring	Opisthopterus macrops (Günther, 1867)	cm	cm	kg	years		[83]		[84]	Least concern[85]
	Dove's longfin herring	Opisthopterus dovii (Günther 1868)	cm	cm	kg	years		[86]		[87]	Least concern[88]
	Hatchet herring	Ilisha fuerthii (Steindachner, 1875)	cm	cm	kg	years		[89]		[90]	Least concern[91]
	Panama longfin herring	Odontognathus panamensis (Steindachner, 1876)	cm	cm	kg	years		[92]		[93]	Least concern[94]
	Tropical longfin herring	Neoopisthopterus tropicus (Hildebrand 1946)	cm	cm	kg	years		[95]		[96]	Least concern[97]
	Vaqueira longfin herring	Opisthopterus effulgens (Regan 1903)	cm	cm	kg	years		[98]		[99]	Vulnerable[100]
	Equatorial longfin herring	Opisthopterus equatorialis Hildebrand, 1946	cm	cm	kg	years		[101]		[102]	Least concern[103]
Wolf herring	Dorab wolf-herring	Chirocentrus dorab (Forsskål, 1775)	100 cm	60 cm	kg	years	4.50	[104]	[105]	[106]	Not assessed
	Whitefin wolf-herring	Chirocentrus nudus Swainson, 1839	100 cm	cm	0.41 kg	years	4.19	[107]		[108]	Not assessed
Freshwater whitefish	Lake herring (cisco)	Coregonus artedi Lesueur, 1818	cm	cm	kg	years		[109]		[110]	Not assessed

Characteristics[link]

The Atlantic herring, Clupea harengus

The species of Clupea belong to the larger family Clupeidae (herrings, shads, sardines, menhadens), which comprise some 200 species that share similar features. These silvery-colored fish have a single dorsal fin, which is soft, without spines. They have no lateral line and have a protruding lower jaw. Their size varies between subspecies: the Baltic herring (Clupea harengus membras) is small, 14 to 18 centimeters; the proper Atlantic herring (C. h. harengus) can grow to about 46 cm (18 inches) and weigh up 700 g (1.5 pounds); and Pacific herring grow to about 38 cm (15 inches).

Life cycle[link]

Herring spawn

At least one stock of Atlantic herring spawns in every month of the year. Each spawns at a different time and place (spring, summer, autumn and winter herrings). Greenland populations spawn in 0–5 metres (0–16 ft). North Sea (bank) herrings spawn at up to 200 metres (660 ft) in autumn. Eggs are laid on the sea bed, on rock, stones, gravel, sand or beds of algae. "...the fish were darting rapidly about, and those who have opportunity to see the fish spawning in more shallow water ... 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" (Moore at Cross Island, Maine).

Females may deposit from 20,000 up to 40,000 eggs, according to age and size, averaging about 30,000. In sexually mature herrings, the genital organs grow before spawning, reaching about one-fifth of its total weight.

The eggs sink to the bottom, where they stick in layers or clumps to gravel, seaweeds or stones, by means of their coating mucus, or to any other objects on which they chance to settle.

If the egg layers are too thick they suffer from oxygen depletion and often die, entangled in a maze of fucus. They need substantial water microturbulence, generally provided by wave action or coastal currents. Survival is highest in crevices and behind solid structures, because predators feast on openly disposed eggs. The individual eggs are 1 to 1.4 millimetres (0.039 to 0.055 in) in diameter, depending on the size of the parent fish and also on the local race. Incubation time is about 40 days at 3 °C (37 °F), 15 days at 7 °C (45 °F), 11 days at 10 °C (50 °F). Eggs die at temperatures above 19 °C (66 °F).

The larvae are 5 to 6 millimetres (0.20 to 0.24 in) long at hatching, with a small yolk sac that is absorbed by the time the larva reaches 10 millimetres (0.39 in) is reached. Only the eyes are well pigmented (a camera works only with a black housing). The rest of the body nearly transparent, virtually invisible under water and natural luminance conditions.

The dorsal fin forms at 15 to 17 millimetres (0.59 to 0.67 in), the anal fin at about 30 millimetres (1.2 in)—the ventral fins are visible and the tail becomes well forked at 30 to 35 millimetres (1.4 in)—at about 40 millimetres (1.6 in) the larva begins to look like a herring.

The larvae are very slender and can easily be distinguished from all other young fish of their range by the location of the vent, which lies close to the base of the tail. But distinguishing clupeoids one from another in their early stages, requires critical examination, especially telling herring from sprats.

At one year they are about 10 centimetres (3.9 in) long, first spawning at 3 years.

Egg to juvenile

Transparent eggs with the yolk and eyes visible and one larva hatched.

Freshly hatched larva in a drop of water besides a match to demonstrate how tiny it is. The black eyes and the yolk are visible.

Young larva in typical oblique swimming position, with remaining yolk still attached. Another larva at the upper right is in the classical S-shape of the beginning phase of attacking a copepod.

Still transparent juvenile herring, about 38 mm long and 3 months old. Visible are the otoliths, the gut, the silvery swimbladder and the heart.

Ecology[link]

Prey[link]

Herrings are a prominent converter of zooplankton into fish, consuming copepods, arrow worms, pelagic amphipods, mysids and krill in the pelagic zone. Conversely, they are a central prey item or forage fish for higher trophic levels. The reasons for this success is still enigmatic; one speculation attributes their dominance to the huge, extremely fast cruising schools they inhabit.

Young herring feed on phytoplankton and as they mature they start to consume larger organisms. Adult herring feed on zooplankton, tiny animals that are found in oceanic surface waters, and small fish and fish larvae. Copepods and other tiny crustaceans are the most common zooplankton eaten by herring. During daylight herring stay in the safety of deep water, feeding at the surface only at night when there is less chance of being seen by predators. They swim along with their mouths open, filtering the plankton from the water as it passes through their gills. Young herring mostly hunt copepods individually, by means of "particulate feeding" or "raptorial feeding",^[111] a feeding method also used by adult herring on larger prey items like krill. If prey concentrations reach very high levels, as in microlayers, at fronts or directly below the surface, herring become filter feeders, driving several meters forward with wide open mouth and far expanded opercula, then closing and cleaning the gill rakers for a few milliseconds.

Copepods, the primary zooplankton, are a major item on the forage fish menu. Copepods are typically one millimetre (0.04 in) to two millimetres (0.08 in) long, with a teardrop shaped body. Some scientists say they form the largest animal biomass on the planet.^[112] Copepods are very alert and evasive. They have large antennae (see photo below left). When they spread their antennae they can sense the pressure wave from an approaching fish and jump with great speed over a few centimeters. If copepod concentrations reach high levels, schooling herrings adopt a method called ram feeding. In the photo below, herring ram feed on a school of copepods. They swim with their mouth wide open and their opercula fully expanded.

Hunting copepods

This copepod has its antenna spread (click to enlarge). The antenna detects the pressure wave of an approaching fish.

Slow motion loop of a juvenile herring hunting copepods. The herring approaches from below and catches copepods individually. Note the copepod at the centre that escapes to the left.

School of herrings ram feeding on a school of copepods with opercula and mouth expanded. The fish swim in a grid with a distance of the jump length of their prey, as indicated by the animation at the right.

Animation showing how herrings hunting in a synchronised way can capture the very alert and evasive copepod

The fish swim in a grid where the distance between them is the same as the jump length of their prey, as indicated in the animation above right. In the animation, juvenile herring hunt the copepods in this synchronised way. The copepods sense with their antennae the pressure-wave of an approaching herring and react with a fast escape jump. The length of the jump is fairly constant. The fish align themselves in a grid with this characteristic jump length. A copepod can dart about 80 times before it tires. After a jump, it takes it 60 milliseconds to spread its antennae again, and this time delay becomes its undoing, as the almost endless stream of herrings allows a herring to eventually snap the copepod. A single juvenile herring could never catch a large copepod.^[111]

Other pelagic prey eaten by herrings includes fish eggs, larval snails, diatoms by larvae below 20 millimetres (0.79 in), tintinnids by larvae below 45 millimetres (1.8 in), molluscan larvae, menhaden larvae, krill, mysids, smaller fishes, pteropods, annelids, Calanus, Centropagidae and Meganyctiphanes norvegica.

Herrings, along with cod and sprat, are the most important species^{[clarification needed]} in the Baltic Sea.^[113] The analysis of the stomach contents of these fish indicate cod is the top predator, preying on the herring and sprat.^[114][113] Sprat are competitive with herrings for the same food resources. This is evident in the two species' vertical migration in the Baltic Sea, where they compete for the limited zooplankton that is available and necessary for their survival.^[115] Sprat are highly selective in their diet and eat only zooplankton, while herrings are more eclectic, adjusting their diet as they grow in size.^[115] In the Baltic, copepods of the genus Acartia can be present in large numbers. However, they are small in size with a high escape response, so herring and sprat avoid trying to catch them. These copepods also tend to dwell more in surface waters, whereas herrings and sprat, especially during the day, tend to dwell in deeper waters.^[115]

Predators[link]

Seabirds, like this European Herring Gull, attack herring schools from above

Humpback whales attack herring schools by lunging from below

See also: Predator avoidance in schooling fish, Bait ball

Predators of herring include seabirds, marine mammals such as dolphins, porpoises, orca, whales, seals and sea lions, predator fish such as sharks, billfish, tuna, salmon, striped bass, cod and halibut, and fishermen.

The predators often operate cooperatively in groups, using different techniques to panic or herd a school of herrings into a tight bait ball. Different predators species then use different techniques to pick the fish off in the bait ball. The sailfish raises its sail to make it appear much larger. Swordfish charge at high speed through the bait balls, slashing with their swords to kill or stun prey. They then turn and return to consume their "catch". Thresher sharks use their long tails to stun the shoaling fish. These sharks compact their prey school by swimming around them and splashing the water with their tails, often in pairs or small groups. They then strike them sharply with the upper lobe of their tails to stun them.^[116] Spinner sharks charge vertically through the school, spinning on their axis with their mouths open and snapping all around. The shark's momentum at the end of these spiraling runs often carries it into the air.^[117][118]

Some whales lunge feed on bait balls.^[119] Lunge feeding is an extreme feeding method, where the whale accelerates from below the bait ball to a high velocity and then opens its mouth to a large gape angle. This generates the water pressure required to expand its mouth and engulf and filter a huge amount of water and fish. Lunge feeding by the huge rorqual whales is said to be the largest biomechanical event on Earth.^[120]

More images
Sailfish herd with their sails Swordfish slash with their swords Thresher shark strike with their tails Spinner shark spin on their axis External videos Humpback Whale: Hunting Technique - YouTube Bait Ball Feast - Nature's Great Events

Fisheries[link]

↑  Global commercial capture of herrings
in million tonnes reported by the FAO 1950–2010^[121]

↑  All herrings 2010 ^[121]
Green = Clupea herrings

Commercial herring catch

Adult herring are harvested for their flesh and eggs, and they are often used as baitfish. The trade in herring is an important sector of many national economies. In Europe the fish has been called the "silver of the sea", and its trade has been so significant to many countries that it has been regarded as the most commercially important fishery in history.^[122]

Environmental Defense have suggested that the Atlantic herring (Clupea harengus) fishery is one of the more environmentally responsible fisheries.^[123]

Detailed time series
Global capture of herrings in tonnes reported by the FAO ↑  Clupea herrings, 1950–2010 [121] ↑  Other herrings, 1950–2010 [121]

As food[link]

A kipper or split smoked herring

Herring has been a staple food source since at least 3000 B.C. There are numerous ways the fish is served and many regional recipes: eaten raw, fermented, pickled, or cured by other techniques.

Herring are very high in the long-chain Omega-3 fatty acids EPA and DHA.^[124] They are a source of vitamin D.

Water pollution influences the amount of herring that may be safely consumed. For example, large Baltic herring slightly exceeds recommended limits with respect to PCB and dioxin, although some sources point out that cancer-reducing effect of omega-3 fatty acids is statistically stronger than the cancer-causing effect of PCBs and dioxins.^[125] The contaminant levels depend on the age of the fish which can be inferred from their size. Baltic herrings larger than 17 cm may be eaten twice a month, while herrings smaller than 17 cm can be eaten freely.^[126] Mercury in fish also influences the amount of fish that women who are pregnant or planning to be pregnant within the next one or two years may safely eat.

History[link]

Historical images

Paintings Still life with herring and stoneware jug, Georg Flegel, c. 1600 Still life with a glass of beer and smoked herring on a plate, Pieter Claesz 1636 Still Life with smoked herrings on yellow paper, Van Gogh 1889 Blue herrings, Engels Kozlov 1965 Herring boats The herring buss 1789 Norse herring boat Reaper, typical of the herring boats that used to operate in Scotland during the early twentieth century The last surviving steam drifter of the Great Yarmouth herring fleet, Norfolk. Drifters were designed to catch herrings in a long drift net. General history Herring monger, ca 1500 Medieval herring fishing in Scania, 1555 17th century herring factory in Amsterdam Processing river herrings [127] The Dutch herring fleet, c. 1700 Barrels for storing salted herring, c. 1465 at the archaeological site of Walraversijde, Belgium Japanese Pacific herring fisherman's house in the historic village of Hokkaid, Sapporo Press for extracting oil from herrings in the historic village "Last Tuesday se'nnight three men met at the Crown Inn, Everley, and for a trifling wager, ate 6o red herrings, with three half-gallon loaves, and drank six gallons of beer"[128] - 1792

Stone hedgebank constructed with a herringbone pattern

Notes[link]