8 Facts That Prove Fish Are Intelligent and Feel Pain

Posted by on March 21, 2017 | Permalink

Anyone who’s seen a fish trapped in net, dangling from a fishing line, or floundering on the deck of a boat is sure to recognise that these animals experience pain and distress. If there were still any doubt, research continues to show that fish are far more intelligent and complex than we give them credit for – and they certainly have the capability to suffer when dragged from the water to feed humans’ demand for their flesh.

  • Fish, like “higher vertebrates”, have neurotransmitters such as endorphins that relieve suffering – and the only reason for their nervous systems to produce these chemicals is to alleviate pain.
  • They communicate using a range of low-frequency sounds and show affection by rubbing against each other.

  • Researchers have found that fish respond with distress to damaging stimuli and harmful substances, showing reactions comparable to those seen in mammals.
  • Fish live in complex social communities in which they keep track of individuals and learn from one another.


  • Some species build nests for their eggs by moving stones, and others build intricate sandcastle “love nests” to attract a mate.

  • Contrary to what many people think, fish have excellent memories. They remember predators and threats such as fishing hooks – and actively avoid them.
  • Sensory receptors found in fish resemble those in amphibians, birds, and mammals, including humans.
  • Studies have shown that fish display signs of Machiavellian intelligence, such as cooperation and reconciliation.

Billions of fish are hauled from the seas every year, and many are left to suffocate on the decks of boats. Scientists estimate that it can take up to 15 minutes before they lose consciousness. Other fish’s gills are cut, or their throats and bellies are sliced open while they’re still alive. The sheer magnitude of the suffering caused by the fishing industry is staggering, since other animals fall victim to this mass killing, too. “Non-target” species also caught in trawlers’ nets include turtles, birds, sharks, dolphins, and whales.

If the deaths of billions of sea animals weren’t bad enough, fishing is an environmental disaster on an enormous scale. An estimated 90 per cent of the world’s oceans are fully exploited or overfished, and this problem is only set to worsen. Please choose sustainable and animal-friendly vegan options instead.