Fish Facts
Aquatic animals, invertebrates and vertebrates, live in aquatic environments for most or all of their lifetime. More fish are killed each year for food than any other animal, and yet they have been excluded from animal welfare policies and denied respect and compassion from the general public.
Here are some interesting facts about fish sentience and intelligence, fishing practices, the aquarium trade, fish in laboratories, whaling and shark finning, ocean conservation, other marine species and environments.
How many aquatic animals are killed annually?
Aquaculture: approximately 100 billion (source: Fishcount.org.uk. http://fishcount.org.uk/fish-count-estimates-2/numbers-of-farmed-fish-slaughtered-each-year)
Capture fisheries: approximately 2-3 trillion (source: Fishcount.org.uk. http://fishcount.org.uk/fish-count-estimates-2/numbers-of-fish-caught-from-the-wild-each-year)
One farmed salmon needs to eat 9 herrings, or 120 anchovies, to be brought to slaughter weight. (source: https://ali.fish/blue-loss)
Between 0.79 and 2.3 trillion fish are caught in the wild each year. This estimate is based on registered landings only and only for fish; it excludes other types of aquatic animals, illegal, unreported, and unregulated (IUU) fishing, bycatch, discards, and recreational and artisanal fishing. Therefore, we use 2-3 trillion as an estimate for all aquatic animals caught in the wild.
Fish are caught and killed 17x MORE than the number of land animals farmed annually around the globe. (source: https://ali.fish/blue-loss)
Additional Facts and Resources:
Fish sentience:
(source: https://sentientmedia.org/do-fish-feel-pain/)
Scientists have confirmed that fish do feel pain. Fish have brains, central nervous systems and pain receptors (nociceptors).
Fish demonstrate a number of physical responses to pain: for example, hyperventilation, rubbing parts of their body that have been injected with acid, suspension of feeding and reduced activity.
Fish have a lateral line system which is a system of tactile sense organs that run through the span of the body, allowing them to detect changes in pressure and movement. The change in pressure when a fish is pulled out of the water causes the sensitive fish immense suffering.
Fish naturally produce opioids which are created by the body in response to pain. These act as the body’s innate painkillers which shows us evidence that fish do feel pain.
Sensitive cells in a fish can detect harmful stimuli, generating a reflex reaction that moves the fish away from the harmful stimulus (“nociception”). This response can be suppressed by painkillers and returns when the painkillers are reversed.
A fish’s eyesight is comparable to that of humans and they have taste buds both inside and outside of their mouths. This way they can detect hints of food through the water current.
In fishing practices, fish are killed by asphyxiation, gill cutting or gutting.
It can take over an hour for a fish to die from asphyxiation, during which time the fish gasps and flaps, building up lactic acid wastes in its muscles which disrupts its metabolism.
Farmed fishes suffer from the poor conditions in which they are kept. Overcrowding increases the risk of disease, fish cannot escape from aggressive fish or express natural behaviours, and being handled by workers causes them stress and injury. (source: https://faunalytics.org/what-does-fish-sentience-mean-for-fisheries/)
Fish Intelligence:
Fish have impressive cognitive abilities, including the ability to learn skills, use tools, build complex social relationships and recognize human faces.
Fish have a long-term memory, allowing them to avoid harmful experiences in the future (“avoidance learning”).
General facts about fishing:
Bottom trawling is one of the most destructive fishing techniques, whereby a fishing net is pulled through the water behind one or more boats, catching fish and destroying the seafloor and marine habitats. Fish are caught hours before being taken out of the water and many others are discarded.
Some wild fish can remember being caught for up to 11 months. (source: https://infogram.com/1p9yngkzmr7v12f7k1v26ekd3kf35d1522m)
In 2016, the United Nations Food and Agriculture Organization reported that 89.5% of fish stocks are fully fished or overfished. (source: https://oceana.org/marine-life/ocean-fishes)
General facts about marine mammals:
(source: https://infogram.com/1p9yngkzmr7v12f7k1v26ekd3kf35d1522m)
Marine mammals play different roles in the ocean: herbivores (manatees), filter feeders (baleen whales), and top predators (killer whales).
Weighing up to 400,000 pounds and reaching 98 feet in length, the Antarctic blue whale is the largest animal on the planet.
Some land mammals that evolved on land 160 million years ago ventured back into the ocean.
General facts about Cephalopods, Crustaceans, Shellfish:
(source: https://infogram.com/1p9yngkzmr7v12f7k1v26ekd3kf35d1522m)
Colossal squid are the largest invertebrates and have the largest eyes of all animals.
Octopuses have 3 hearts and squirt ink to deter predators.
There are over 52,000 species of crustaceans.
General facts about corals & Invertebrates:
(source: https://infogram.com/1p9yngkzmr7v12f7k1v26ekd3kf35d1522m)
Coral reefs only cover around 1% of the ocean but are home to around 25% of all known marine species.
Barnacles transition from a brief phase as larvae and then settle, never moving again.
American oysters are filter feeders and each one filters around 50 gallons of water per day.
Corals are used in jewelry making and in souvenirs, however people are unaware that they are made of living creatures, by living creatures.
Fish that live on coral reefs can live up to 40 years. (source: https://www.dropbox.com/s/vboqmtvmuo9iq2m/Respect4Fish-FullPagePDF.pdf?dl=0)
Coral reefs produce 50% of the Earth’s oxygen and fish feeding on the algae that grows on coral reefs enables them to continue growing. (source: https://www.dropbox.com/s/vboqmtvmuo9iq2m/Respect4Fish-FullPagePDF.pdf?dl=0)
Species-specific facts/information:
It is estimated that around 20,000 species of fish live in the world’s oceans. (source: https://oceana.org/marine-life/ocean-fishes)
Attitudes about the ocean:
A study with 23,737 respondents from around the world showed that people consider pollution to be the #1 threat to our oceans, with fishing being the 2nd biggest threat. (source: https://infogram.com/1pplmj7wk3wmm3ir635y2qjwvzizxrkvd25)
Fish consumption:
Fish catch is recorded by live weight rather than by individual fish, so it is difficult to quantify the exact number of fish caught over time. (source: https://infogram.com/1p0lvvzwewr10yhexe5vq1k11gin7wzk3j3)
An estimated 4,756,997 tons of fish were slaughtered in the United States in 2018 and 14,831,310 fish were slaughtered in China in the same year. (source: https://faunalytics.org/fundamentals-ocean-life/)
Bycatch & Ghost Gear:
(source: https://faunalytics.org/fundamentals-ocean-life/)
Catching wild fish also involves catching “non-target” species or “bycatch”. Sharks, turtles, seals, and other unwanted species are caught in the process and thrown back into the ocean, often dead.
Ghost fishing gear is the discarded or lost fishing gear that continues to entangle, trap and kill marine species.
640,000 tons of ghost fishing gear enters the oceans each year.
Ghost gear and derelict fishing traps kill approximately 136,000 marine mammals each year and make up 10% of the plastic entering the oceans.
10.8% of fish taken from the oceans annually are bycatch (approximately 9.1 million tons).
Bottom trawling accounts for 46% of bycatch.
US fish pet market:
(source: https://faunalytics.org/fundamentals-ocean-life/)
158,100,000 fish live in United States homes as “companion animals”. By number they are the most common companion animal.
Approximately $1.1 billion are spent on companion fish in the United States.
82% of companion fish have been purchased at pet stores.
2% of fish are included in wellness plans or covered by insurance.
Lab use of fish:
(source: https://faunalytics.org/fundamentals-ocean-life/)
In 2018, 17% of experimental laboratory procedures used fishes. Fish are the 2nd most-used animals after mice (60%).
In the past 5 years, there has been a 5% increase in the number of fishes used in laboratory experiments, while the use of mice and rats is declining.
In 2018, 216,025 genetically altered fishes were used for specialized breeding in the UK.
194,285 fishes (65.24% of laboratory fish) are used in the UK for basic scientific experiments which aim to build on scientific knowledge but do not require a concrete outcome (“research for research’s sake”). 10,085 fishes (3.39% of laboratory fish) are used in experiments that aim to protect the environment.
Aquarium trade:
Reefs are being stripped for hobby tanks in Hawaii, Thailand, Indonesia, the Philippines, Africa and the Virgin Islands.
27 million fish are currently in the aquarium trade.
Reef animals that are caught with nets are starved, have their bladders pierced with needles, and their fins cut with scissors. They are transported in plastic bags in airplanes to aquarium suppliers and many die during travel or after 6 months in captivity.
Fish are sometimes stunned with dynamite or cyanide which destroys corals.
Wild fish are taken from the vast ocean into captivity and are forced to swim around in small pet tanks or bowls.
In the past 50 years, 30% of coral reefs died and another 30% suffered severe damage.
3 in 5 of all remaining reefs could die in the next 25 years.
Whaling:
(source: https://faunalytics.org/fundamentals-ocean-life/)
Whales are killed for subsistence hunting, meat sales, and research (whaling).
88 countries are members of the International Whaling Commission.
12 species of whales are monitored by IWC.
After being harpooned, whales can suffer for 25 minutes.
Norway, Japan, Iceland and South Korea allow commercial whaling.
The US, Canada, Russia, Greenland, Faroe Islands, Indonesia and St. Vincent allow whaling by aboriginal peoples.
Whale Sanctuaries
As of 2021, there are 59 orcas in captivity, 27 of which were taken from the wild and 32 born in captivity. In the wild, these orcas could live 50-80 years but in captivity, they will die prematurely at 20-30 years.
The Whale Sanctuary Project offers whales who have been in captivity at entertainment parks a natural habitat that is considerably larger than a typical on-land aquarium. This sanctuary will be 100 times larger than the largest aquarium tank.
In the Whale Sanctuary, whales will be able to express natural behaviours such as exploring, swimming and diving among other marine species and at variable depths.
Shark finning:
(source: https://faunalytics.org/fundamentals-ocean-life/)
Sharks are killed for their fins which are used in shark fin soup (shark finning).
80 countries have a full or partial ban on shark finning or shark fishing.
73 million sharks are killed and traded each year.
Over 28% of shark species are endangered, critically endangered, threatened or vulnerable.
Possession and sale of shark fins is only banned in 13 states.
Ocean conservation issues: MPAs, coral bleaching, overfishing, climate change, ocean acidification, plastics pollution
MPAs:
(source: https://www.iucn.org/resources/issues-briefs/marine-protected-areas-and-climate-change)
Marine protected areas (MPAs) are areas of the ocean that are protected for long-term conservation aims.
6.35% of the ocean is protected but only 1.89% of that area does not permit fishing, mining, drilling, or other extraction activities.
Most MPAs do not have sufficient human and financial resources
There is a lack of strictly and permanently protected MPAs and in order to alleviate the impacts of climate change on the oceans (such as warming oceans), significant cuts in greenhouse gas emissions are needed.
MPAs are not only important for ecological protection but also for social resilience. Coral reefs, mangroves, wetlands and barrier islands are the natural infrastructure that shield the land (for example from storms). MPAs that protect these infrastructures are simultaneously protecting the vulnerability of humans.
MPAs create areas of reduced stress, allowing marine organisms to adapt to climate change and allowing species to move around and escape certain pressures.
MPAs where stressors are controlled can be used as research sites to track the impacts of climate change.
What can be done?
Cutting emissions, improving protection schemes for ecosystems to maintain and rebuild resilience, implementing sustainable practices in all industries will help in addressing impacts of climate change on the oceans.
Integrated Coastal Zone Management (ICZM) and Marine Spatial Planning (MSP) can be implemented by countries to improve the management of MPAs and meet sustainable development, biodiversity conservation, and climate change adaptation and mitigation objectives.
The Green Climate Fund (GCF) offers support to developing countries to receive support for adaptation and mitigation strategies, focusing on biodiversity conservation and protected area management.
National, regional and international political commitments can help strengthen the governance of, and resources available to, MPA programmes.
Coral bleaching
(source: https://faunalytics.org/fundamentals-ocean-life/)
Coral bleaching occurs when warm sea temperatures persist over time and this has become a major issue as climate change causes mass bleaching events.
25% of all marine species live among coral reefs.
1/5 of all the coral in the world has died since 2015 and between 2014 and 2017, bleaching has damaged 75% of the world’s coral reefs.
In the US, 22 coral species are listed as threatened and 3 are endangered.
It takes 100,000 - 30,000,000 years for a barrier reef to reach full maturity.
33% of reef building corals are threatened by rising sea temperatures.
Overfishing
(source: https://faunalytics.org/fundamentals-ocean-life/)
The FAO states that around 94% of fish stocks are fished to the maximum sustainable degree.
Climate change
(source: https://faunalytics.org/fundamentals-ocean-life/)
Rising levels of greenhouse gases prevent heat from the Earth’s surface to be released into space. Much of the excess atmospheric heat travels back to the ocean which results in higher temperatures in the surface levels of the ocean.
Ocean acidification
(source: https://faunalytics.org/fundamentals-ocean-life/)
Around 30% of the carbon dioxide released into the atmosphere is absorbed by the ocean, increasing the acidity levels in the ocean.
Plastics pollution
(source: https://faunalytics.org/fundamentals-ocean-life/)
At least 8 million tons of plastic end up in the ocean each year, making up 80% of all marine debris.
Cigarettes are the most common item found in the International Coastal Cleanup, with food wrappers and plastic bottles following.