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Forage fish are small fish which are preyed on by larger predators for food. Predators include other larger fish, seabirds and marine mammals. Typical ocean forage fish are small, filter feeding fish such as herring, anchovies and menhaden.

Forage fish compensate for their small size by forming schools. Some swim in synchronised grids with their mouths open so they can efficiently filter feed on plankton. These schools can become immense shoals which move along coastlines and migrate across open oceans. The shoals are concentrated fuel resources for the great marine predators. The predators are keenly focused on the shoals, acutely aware of their numbers and whereabouts, and make migrations themselves that can span thousands of miles to connect with, or stay connected, with them.

The ocean primary producers, mainly contained in plankton, produce food energy from the sun and are the raw fuel for the ocean food webs. Forage fish transfer this energy by eating the plankton and becoming food themselves for the top predators. In this way, forage fish occupy the central positions in ocean and lake food webs.

In recent times, many of the world great predator fisheries have collapsed. To compensate, the fishing industry is removing huge amounts of forage fish from the oceans, using factory ships with sophisticated sonar and spotting planes. Most of the catch is feed to farmed animals. Fisheries scientists are expressing concern that this will result in further collapses of the predator fish that depend on them.

The word forage comes from the 14th century Old French fourrage, meaning fodder or straw.

In the oceans

Typical ocean forage fish are small, silvery schooling oily fish such as herring, anchovies and menhaden, and other small, schooling baitfish like capelin, smelts, sand lance, halfbeaks, pollock, butterfish and juvenile rockfish. Herrings are a preeminant forage fish, often marketed as sardines or pilchards.

The term “forage fish” is a term used in fisheries, and is applied also to forage species that are not true fish, but play a significant role as prey for predators. Thus invertebrates such as squid and shrimp are also referred to as "forage fish". Even the tiny shrimp-like creatures called krill, small enough to be eaten by other forage fish, yet large enough to eat the same zooplankton as forage fish, are often classified as "forage fish".

Ocean forage fish

	File:6742 aquaimages.jpg
Anchovies	Caribbean reef squid	Menhaden
Sardines	Shrimp	Northern krill

Forage fish are the dominant converters of the enormous ocean production of zooplankton, utilizing the biomass of copepods, mysids and krill in the pelagic zone. They are on the other side a central prey item for higher trophic levels. The dominance of forage fish may be related to their outstanding way of living in huge, and often extremely fast cruising schools.

Though forage fish are abundant, there are relatively few species. There are more species of primary producers and apex predators in the ocean than there are of forage fish.

Ocean food webs

Forage fish occupy central positions in the ocean food webs. The position that a fish occupies in a food web is called its trophic level (Greek trophē = food). The organisms it eats are at a lower trophic level, and the organisms that eat it are at a higher trophic level. Forage fish occupy middle levels in the food web, serving as a dominant prey to higher level fish, seabirds and mammals.

Ecological pyramids are graphical representations, along the lines of the diagram at the right, which show how biomass or productivity changes at each trophic level in a ecosystem. The first or bottom level is occupied by primary producers or autotrophs (Greek autos = self and trophe = food). These are the names given to organisms that do not feed on other organisms, but produce biomass from inorganic compounds, mostly by a process of photosynthesis. These

In oceans, most primary production is performed by algae. This is a contrast to land, where most primary production is performed by vascular plants. Algae ranges from single floating cells to attached seaweeds, while vascular plants are represented in the ocean by groups such as the seagrasses. The larger producers, such as seagrasses and seaweeds, are generally confined to the littoral zone and adjacent shallow waters, where they can attach to the underlying substrate but still be within the photic zone. The majority of primary production in the ocean is performed by microscopic organisms, the phytoplankton.

Thus, in ocean environments, the first bottom trophic level is occupied principally by phytoplankton, microscopic drifting organisms, mostly one-celled algae, that float in the sea. Most phytoplankton are too small to be seen individually with the unaided eye. When present in high enough numbers, they can appear as a green discoloration of the water. Since they increase their biomass mostly through photosynthesis they live in the sun-lit surface layer (euphotic zone) of the sea.

Pytoplankton form the base of the ocean foodchain

Phytoplankton	Dinoflagellate	Diatoms

The most important groups of phytoplankton include the diatoms and dinoflagellates. Diatoms are especially important in oceans, where they are estimated to contribute up to 45% of the total ocean's primary production. Although usually microscopic, some species of diatoms can reach up to 2 millimetres in length.

The second trophic level (primary consumers) is occupied by zooplankton which feed off the pytoplankton. Together with the phytoplankton, they form the base of the food pyramid that supports most of the world's great fishing areas. Zooplankton are tiny animals found with the phytoplankton in oceanic surface waters, and include tiny crustaceans, and fish larvae and fry (recently-hatched fish). Most zooplankton are filter feeders, and they use appendages to strain the pytoplankton in the water. Some larger zooplankton also feed on smaller zooplankton. Some zooplankton can jump about a bit to avoid predators, but they can't really swim. Like phytoplankton, they float with the currents, tides and winds instead. Zooplanktons can reproduce rapidly, their populations can increase up to thirty percent a day under favourable conditions. Many live short and productive lives and reach maturity quickly.

Zooplankton form the second level in the ocean food chain

Segmented worm	Tiny shrimp-like crustaceans	Juvenile planktonic squid

Particularly important groups of zooplankton are the copepods and krill. These are not shown in the images above, but are discussed in more detail later. Copepods are a group of small crustaceans found in the sea and nearly every freshwater habitat. They constitute the biggest source of protein in the oceans, and are important prey for forage fish. Krill constitute the next biggest source of protein. Krill are particularly large predator zooplankton which feed on smaller zooplankton. This means they really belong to the third trophic level, secondary consumers, along with the forage fish.

Together, phytoplankton and zooplankton make up most of the plankton in the sea. Plankton is the term applied to any small drifting organisms that float in the sea (Greek planktos = wanderer or drifter). By definition, organisms classified as plankton are unable to resist ocean currents; they cannot swim against the ambient current and control their position. In ocean environments, the first two tropic levels are occupied mainly by plankton. Plankton are divided into producers and consumers. The producers are the phytoplankton (Greek phyton = plant) and the consumers, who eat the phytoplankton, are the zooplankton (Greek zoon = animal).

What forage fish eat

External image
Forage fish and the food web

Forage fish feed on plankton. When they are eaten by larger predators, they transfer this energy from the bottom of the food chain to the top and in this way are the central link between trophic levels.

Forage fish are usually filter feeders, meaning that they feed by straining suspended matter and food particles from water. They usually travel in large, slow moving, tightly packed schools with their mouths open. They are typically omnivorous. Their diet is usually based primarily on zooplankton, although, since they are omnivorous, they also take in some phytoplankton.

Young forage fish, such as herring, mostly 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 fish larvae and fry (recently-hatched fish). Copepods and other tiny crustaceans are common zooplankton eaten by forage fish. During daylight, many forage fish stay in the safety of deep water, feeding at the surface only at night when there is less chance of predation. They swim along with their mouths open, filtering the plankton from the water as it passes through their gills.

Ocean halfbeaks are omnivores feeding on algae, marine plants such as seagrasses, plankton, invertebrates such as pteropods and crustaceans; and smaller fishes. Some tropical species have been observed to feed on animals during the day and plants at night, while other species alternate between carnivory in the summer and herbivory in the winter. They are in turn eaten by billfish, mackerel, and sharks.

Predators

Forage fish are the food that sustains larger predators above them in the ocean food chain. The superabundance they present in their schools make them ideal food sources for top predator fish such as tuna, striped bass, cod, salmon, barracuda and swordfish, as well as sharks, whales, dolphins, porpoises, seals, sea lions, and seabirds.

Ocean predators of forage fish

File:Tuna.jpg	File:G. cuvier.jpg
Tuna	Shark	Striped bass
File:Albatros ceja negra - paso drake - noviembre 2005.jpg		File:Hawaiian Monk Seal, photo in water.jpg
Albatross	Dolphin	Hawaiian monk seal

Schooling

Forage fish compensate for their small size by forming schools. These sometimes immense gatherings fuel the ocean food web. Most forage fish are pelagic, meaning they form their schools in open water rather than on the bottom (benthic) or near the bottom (demersal). They are short-lived, and go mostly unnoticed by humans, apart from an occasional support role in a documentary about a great ocean predator. While we may not pay them much attention, the great marine predators are keenly focused on them, acutely aware of their numbers and whereabouts, and make migrations that can span thousands of miles to connect with them. After all, forage fish are their food.

Herring are among the most spectacular schooling fish. They aggregate together in huge numbers. Schools have been measured up to 4 cubic kilometers in size, containing an estimated 4 billion fish. These schools move along coastlines and traverse the open oceans. A school of herring in general has a very precise arrangement thus allowing the school to maintain a relatively constant cruising speed. Schools that are made up of an individual stock generally travel in a triangular pattern between their spawning grounds e.g. southern Norway, their feeding grounds (Iceland) and also their nursery grounds (northern Norway). Such wide triangular journeys are probably important because herring feast efficiently on their own offspring. A school of herring can react very quickly to evade predators; they have excellent hearing. The herrings keep a certain distance from a moving scuba diver or cruising predator like a killer whale, forming a vacuole which can look like a doughnut from a spotter plane.. The phenomenon of schooling is however, far from understood, especially the swimming and feeding energetics. Many hypotheses have been put forward to explain the function of schooling, such as predator confusion, reduced risk of being found, better orientation, and synchronized hunting. However, schooling can also have some disadvantages such as: oxygen- and food depletion, excretion buildup in the breathing media. The school array probably gives advantages in energy saving although this is a highly controversial and much debated field.

On calm days, schools of herring can sometimes be detected at the surface from more than a mile away by the little waves they form, or from a few meters at night when they trigger the bioluminescence of surrounding plankton. Underwater recordings show herring constantly cruising at high speeds up to 108 cm per second, with much higher escape speeds.

They are fragile fish, and because of their collective schooling behaviour they are on display in very few aquaria worldwide. Even with the best facilities that these aquaria can offer they appear slim and slow compared to a quivering school in the wild.

Hunting copepods

Copepods are a group of small crustaceans found in the sea and nearly every freshwater habitat. Many species are planktonic (drifting in sea waters), but more are benthic (living on the ocean floor). Copepods are typically 1 millimetre (0.039 in) to 2 millimetres (0.079 in) long, with a teardrop shaped body. Although like other crustaceans they have an armoured exoskeleton, they are so small that in most species this armour, and the entire body, is almost totally transparent.

Copepods are usually the dominant members of the zooplankton. Some scientists say they form the largest animal biomass on earth. They compete for this title with Antarctic krill. Because of their smaller size and relatively faster growth rates, however, and because they are more evenly distributed throughout more of the world's oceans, copepods almost certainly contribute far more to the secondary productivity of the world's oceans than krill, and perhaps than all other groups of organisms together.

Copepods are very alert and evasive. They have large antennae. When they spread their antennae they can sense the pressure wave from an approaching fish and jump with great speed over a few centimeters.

Herrings are pelagic feeders. Their prey consists of a wide spectrum of pytoplankton and zooplankton, amongst which copepods are a dominant prey. Young herring usually capture small copepods by hunting them individually— they approach them from below. The (half speed) video loop at the left shows a juvenile herring feeding on copepods. In the middle of the image a copepod escapes successfully to the left. The opercula (hard bony flaps covering the gills) are spread wide open to compensate the pressure wave which would alert the copepod to trigger a jump.

If prey concentrations reach very high levels, the herrings adopt a method called "ram feeding". They swim with their mouth wide open and their opercula fully expanded. Every several feet, they close and clean the gill rakers for a few milliseconds (filter feeding). In the photo on the right, herring ram feed on a school of copepods. The fish all open their mouths and opercula wide at the same time (the red gills are visible—click to enlarge). 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 below.

In the animation, juvenile herring hunt for the copepods in synchronization: The copepods can sense with their antennae the pressure-wave of the approaching herring and react with a fast escape jump. The length of the jump is fairly constant. The fish arrange in a grid of this characteristic jump length. The copepods can dart about 80 times before they tire out. It takes them 60 milliseconds to spread out their antennae again, and this time slot is utilized often by the herring to finally snap a copepod. A single juvenile herring would never be able to catch a large copepod.

Capelin migration

Capelin are a forage fish of the smelt family found in the Atlantic and Arctic oceans. In summer, they graze on dense swarms of plankton at the edge of the ice shelf. Larger capelin also eat from great deal of krill and other crustaceans. Capelin move inshore in large schools to spawn and migrate in spring and summer to feed in the plankton-rich oceanic area between Iceland, Greenland, and Jan Mayen. Capelin distribution and migration is linked with ocean currents and water masses. Around Iceland maturing capelin usually undertake extensive northward feeding migrations in spring and summer and the return migration takes place in September to November. The spawning migration starts from north of Iceland in December to January.

The diagram on the right shows the main spawning grounds and larval drift routes. Capelin on the way to feeding grounds is coloured green, capelin on the way back is blue, and the breeding grounds are red.

The sardine run

The sardine run is a spectacular migration by millions of silvery sardines along the southern coastline of Africa. In terms of biomass, the sardine run could rival East Africa's great wildebeest migration.

External images
Dolphins herd sardines
Gannets "divebomb" sardines

Sardines have a short life-cycle, living only two or three years. Adult sardines, about two years old, mass on the Agulhas Bank where they spawn during spring and summer, releasing tens of thousands of eggs into the water. The adult sardines then make their way in hundreds of shoals towards the sub-tropical waters of the Indian Ocean. A larger shoal might be 7 kilometers (4 mi) long, 1.5 kilometers (1 mi) wide and 30 meters (100 ft) deep. Huge numbers of sharks, dolphins, tuna, sailfish, Cape fur seals and even killer whales congregate and follow the shoals, creating a feeding frenzy along the coastline.

When threatened, sardines instinctively group together and create massive "bait balls". Bait balls can be up to 20 meters (70ft) in diameter. They are short lived, seldom lasting longer than 20 minutes. As many as 18,000 dolphins, behaving like sheepdogs, round the sardines into these bait balls, or herd them to shallow water (corralling) where they are easier to catch. Once rounded up, the dolphins and other predators take turns plowing through the bait balls, gorging on the fish as they sweep through. Seabirds also attack them from above, flocks of gannets, cormorants, terns and gulls. Some of these seabirds plummet from heights of 30 metres (100 feet), plunging through the water leaving vapour-like trails behind like fighter planes, .

The eggs, left behind at the Agulhas Banks, drift northwest with the current into waters off the west coast, where the larvae mature and develop into juvenile fish. When they are old enough, they aggregate into dense shoals and migrate southwards, returning to the Agulhas banks in order to restart the cycle.

Commercial fishing

History

Herring has been a known staple food source since 3000 B.C. In Roman times, anchovies were the base for the fermented fish sauce called garum that was a staple of cuisine and an item of long-distance commerce produced in industrial quantities.

Fishing for sardela or sardina (Sardina pilchardus) on the Croatian Adriatic coasts of Dalmatia and Istria is an ongoing activity tracing its roots back thousands of years. The region was part of the Roman Empire, then largely a Venetian dominion, and has always been sustained through fishing mainly sardines. All along the coast there are many towns that promote the age-old practice of fishing by lateen sail boats for tourism and on festival occasions. Today this tradition is also continued by many producers.

Pilchard fishing and processing was a thriving industry in Cornwall from around 1750 to around 1880, after which it went into an almost terminal decline. However, as of 2007, stocks are improving (q.v. River Cottage: Gone Fishing 22/11/08). The industry has featured in numerous works of art, particularly by Stanhope Forbes and other Newlyn School artists.

Contemporary

Traditional commercial fisheries were directed towards high value ocean predators such as cod, rockfish and tuna, rather than humble forage fish. As technologies developed, fisheries became so effective at locating and catching predator fish that many of the stocks collapsed. The industry compensated by turning to species lower in the food chain.

In former times, forage fish were more difficult to fish profitably, and were a small part of the global marine fisheries. But modern industrial fishing technologies have enabled the removal of increasing quantities. Industrial-scale forage fish fisheries need large scale landings of fish to return profits. They are dominated by a small number of corporate fishing and processing companies.

Forage fish populations are very vulnerable when faced with modern fishing equipment. They swim near the surface in compacted schools, so they are relatively easy to locate at the surface with sophisticated electronic fishfinders and from above with spotter planes. Once located, they are scooped out of the water using highly efficient nets, such as purse seines, which remove most of the school.

Spawning patterns in forage fish are highly predictable. Some fisheries use knowledge of these patterns to harvest the forage species as they come together to spawn, removing the fish before they have actually spawned. Fishing during spawning periods or at other times when forage fish amass in large numbers can also be a blow to predators. Many predators, such as whales, tuna and sharks, have evolved to migrate long distances to specific sites for feeding and breeding. Their survival hinges on their finding these forage schools at their feeding grounds. The great ocean predators find that, no matter how they are adapted for speed, size, endurance or stealth, they are on the losing side when faced with the machinery of contemporary industrial fishing.

Altogether, forage fish account for 37 percent (31.5 million tonnes) of all fish taken from the world's oceans each year. However, because there are fewer species of forage fish compared to predator fish, forage species fisheries are the largest in the world. Seven of the top ten fisheries target forage fish. The total world catch of herrings, sardines and anchovies alone in 2005 was 22.4 million tonnes, 24 percent of the total world catch.

The Peruvian anchoveta fishery is now the biggest in the world (10.7 million tonnes in 2004), while the Alaskan pollock fishery in the Bering Sea is the largest single species fishery in the world (3 million tonnes). The Alaskan pollock is said to be the largest remaining single species source of palatable fish in the world.. However, the biomass of pollock has declined in recent years, perhaps spelling trouble for both the Bering Sea ecosystem and the commercial fishery it supports. Acoustic surveys by NOAA indicate that the 2008 pollock population is almost 50 percent lower than last year's survey levels. This decline has led some scientists to worry that Alaska pollock could be about to repeat the kind of collapse experienced by Atlantic cod, which could have negative consequences for the world food supply and the entire Bering Sea ecosystem. Halibut, salmon, endangered Steller sea lions, fur seals, and humpback whales all eat pollock and rely on healthy populations to sustain themselves.

Use as animal feed

Eighty percent of the forage fish caught are feed to animals. Ninety percent is processed into fishmeal and fish oil. Of this, 46 percent was feed to farmed fish, 24 percent to pigs, and 22 percent to poultry (2002). Six times the weight of forage fish is feed to pigs and poultry alone than the entire seafood consumption of the U.S. market.

According to Turchini and De Silva (2008), another 2.5 million tonnes of the annual forage fish catch is consumed by the global cat food industry each year. In Australia, pet cats eat 13.7 kilograms of fish a year compared to the 11 kilograms eaten by the average Australian. The pet food industry is increasingly marketing premium and super-premium products, when different raw materials, such as the by-products of the fish filleting industry, could be used instead.

Environmental issues

A recent study (2008) by fisheries scientists Jacqueline Alder, Daniel Pauly and colleagues is the product of a nine-year Sea Around Us Project. The study concludes that...

1. The composition of landings of forage fish fisheries have changed over the past 50 years with the trophic level of fish used in fishmeal increasing over the past 20 years.
2. Our understanding of the role of forage fish in marine ecosystem and the impact of fishing is still limited.
3. Landing of forage fish peaked by the 1970s, and these high levels are highly unlikely in the future, even if fisheries are managed sustainably.
4. The consumption of forage fish by seabirds and marine mammals is not likely to be onerous to fisheries, except in a few localized areas. By contrast, fisheries, by reducing the biomass of small pelagics, might pose a threat to these predators, particularly to those species for which stocks have been heavily depleted by human exploitation in the past.
5. Some forage fish species are consumed by many people with consumption patterns changing over the last 20 years.
6. Aquaculture continues to increase its consumption of fishmeal and fish oil.

The U.S. National Coalition for Marine Conservation is asking U.S. fishery managers to put "Forage First!". Their campaign was launched with the publication of their report, Taking the Bait: Are America’s Fisheries Out-competing Predators for their Prey? The report is available at cost to the U. S. fishing industry, and encourages fishery managers to protect predator-prey relationships as a first step toward an ecosystem based approach to fishery management.

In lakes and rivers

Forage fish also inhabit freshwater habitats, such as lakes and rivers, where they serve as food for larger freshwater predators. Usually smaller than 15 centimetres (6 in) in length, these small bait fish make up most of the fish found in lakes and rivers. The minnow family alone, consisting of minnows, chubs, shiners and daces, consists of more than fifty species. Other freshwater forage fish include suckers, killifish, shad, bony fish as well as fish of the sunfish family, excluding black basses and crappie, and smaller species of the carp family. There are also anadromous forage fish, such as eulachon.

Freshwater forage fish

Golden shiner	Killifish	Southern redbelly dace
		File:Alosa fallax.png
Chinese minnow	Swarm of carp	Twaite shad

Within any fresh or saltwater ecosystem, there will always be both desirable and undesirable fishes, and this varies from country to country, and often from region to region within a country. Sport fishermen divide freshwater predators of forage fish into those:

• which have a good fighting ability and are good to eat, called sport (or game) fish.
• the other less desirable fish, called rough fish in North America and coarse fish in Britain

Rough or coarse fish usually refers to fish that are not commonly eaten, not sought after for sporting reasons, or have become an invasive species that reduce the populations of desirable fish. They compete for forage fish with the more popular sport fish. They are often regarded as a nuisance, and are not usually protected by game laws. Forage fish generally are not considered rough or coarse fish because of their usefulness as bait.

The term rough fish is used by U.S. state agencies and anglers to describe undesirable predator fish. In North America, anglers fish for salmon, trout, bass, pike, catfish, walleye and muskellunge. The smallest fish are called panfish, because they can fit in a normal cooking pan. Examples are crappies, perch, rock bass, bluegill and sunfish.

The term coarse fish originated in the United Kingdom in the early 19th century. Prior to that time, recreational fishing was a sport of the gentry, who angled for salmon and trout which they called "game fish". Other fish were disdained as "coarse fish". These days, "game fish" refers to Salmonids (other than grayling) – that is, salmon, trout and char. Coarse fish are made up mostly of the larger species of Cyprinids (carp, roach, bream) as well as gars and lampreys. Coarse fish are no longer disdained; indeed, fishing for coarse fish has become a popular pastime.

Freshwater predators of forage fish

Brook trout	Black crappie	Macquarie perch
Rainbow trout	Pink salmon	Channel catfish

Notes

1. ^ Kils, U (1992) The ecoSCOPE and dynIMAGE: Microscale tools for in situ studies of predator-prey interactions. Arch Hydrobiol Beih 36: 83-96
2. ^ National Coalition for Marine Conservation: Forage fish
3. U.S. Geological Survey: Forage Fish Alaska Science Center
4. ^ Alder, Jacqueline; Campbell, Brooke; Karpouzi, Vasiliki; Kaschner, Kristin and Pauly, Daniel (2008) Forage Fish: From Ecosystems to Markets, Annual Review of Environment and Resources, Vol. 33, pp 153–166.
5. ^ Marine Fish Conservation Network: Forage fish: The Most Important Fish in the Sea]
6. Mann, D. G. (1999). The species concept in diatoms. Phycologia 38, 437-495.
7. Biology of Copepods at Carl von Ossietzky University of Oldenburg
8. Forage fish: The most important fish in the sea
9. Randall, J (1967). "Food habits of reef fishes of the West Indies" (PDF Converted to digital format by NOAA, 2004). Studies in Tropical Oceanography. 5: 665–847.
10. Tibbetts, I (2005). "Trophic shifts in three subtropical Australian halfbeaks (Teleostei: Hemiramphidae)". Marine & Freshwater Research. 56: 925–932. doi:10.1071/MF04305. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
11. Mahmoudi, B (2002). "A review of Florida's halfbeak bait fishery and halfbeak biology, and a preliminary stock assessment" (PDF). Florida Fish and Wildlife Conservation Commission. {{cite web}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
12. Nøttestad, L and Axelsen, BE (1999) Herring schooling manoeuvres in response to killer whale attacks Canadian Journal of Zoology, 77: 1540-1546.
13. Pitcher, TJ (1993) Behaviour of Teleost Fishes, Chp 12: Functions of shoaling behaviour in teleosts Springer. ISBN 9780412429309
14. Marine Scientists Scratch Heads Over Sardines
15. ^ Sardine Run Shark Feeding Frenzy Phenomenon in Africa Cite error: The named reference "baitball" was defined multiple times with different content (see the help page).
16. FAO (2005) Review of the state of world marine fishery resources. Fisheries technical paper T457, ISBN 95-5-105267-0
17. Clover, Charles. 2004. The End of the Line: How Overfishing is Changing the World and What We Eat. Ebury Press, London. ISBN 0-09-189780-7
18. Pollock: Poster fishery on the brink
19. Greenpeace: Rethinking sustainability: A new paradigm for fisheries management
20. World's Fish Catches Being Wasted As Animal Feed Terra Daily. Retrieved 1 Dec 2008.
21. New Study to Highlight Waste of Seafood The FishSite. Retrieved 1 Dec 2008
22. Pets’ gourmet tastes put pressure on fish stocks – Deakin University
23. National Coalition for Marine Conservation: Forage First!
24. ^ Kleber, John E (1992) The Kentucky Encyclopedia University Press of Kentucky, Page 320. ISBN 9780813117720
25. Lowerson, John (1993) Sport and the English middle classes, 1870-1914. Manchester University Press. ISBN 0719037778

External links

• Herring Research: Using Acoustics to Count Fish.
• Sanders, Michael (1995) Impacts of predator-prey relationships on harvesting strategies and management] FAO.
• Daniel Pauley at Fish Forever - Youtube: Pauley talks about his "epiphany" about directly eating anchovies.

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