Each year, up to 2.7 trillion fishes are killed for food—more than any other animal on Earth. Yet, fishes are rarely part of discussions about sentience, justice, or compassion. Scientific evidence confirms that fishes feel pain, suffer, and experience pleasure. Whether briefly admired in aquariums or dismissed and eaten, these misunderstood animals show remarkable intelligence and emotional depth.

Harvard researchers found that carp can distinguish music genres. Trained to tell between blues and classical, they even recognized new music within those styles and differentiated synthesized versions, revealing sophisticated memory and auditory processing.

Some eels approach familiar divers for strokes and chin rubs, and can swim up to 3,700 miles during migration. Cuttlefish—relatives of octopuses but with fins too—can instantly change their skin color and texture to blend in or communicate. They also solve puzzles and remember solutions, showing curiosity and even frustration when food rewards don’t come.

Archerfish can identify a specific human face among 44 strangers. 

The wrasse family of fish exhibits surprisingly sophisticated behavior, including cleaning parasites off other fish and faking cooperation to steal bites. They can also recognize themselves in mirrors—a trait shared with ants, great apes, dolphins, elephants, magpies, and humans. Napoleon wrasse can live over 30 years, change sex, and solve complex problems.

These aren’t isolated cases. Across species, fishes exhibit cognitive and emotional lives that rival those of mammals and birds. The white-spotted pufferfish, native to Japan's Ryukyu Islands, creates complex, mandala-like sand patterns—often called "underwater crop circles"—to attract mates and protect the eggs laid at the center.

There is growing evidence that fishes possess pain-sensing systems similar to those of land animals. An Italian study revealed that tuna undergo intense physiological stress during capture, with hormone surges signaling extreme suffering. Other research showing that salmon display clear signs of pain when exposed to extreme heat implies that hooking and suffocation would similarly inflict pain.

A 2025 study found that rainbow trout endure prolonged, excruciating pain during air asphyxiation, a common slaughter method. When pulled from the water, their gills collapse as they gasp for oxygen, panicking as carbon dioxide builds. This agony can last up to 25 minutes, in addition to pain from hooking, handling, or stabbing.

As science debunks the myth that fishes are simple and unfeeling, calls for legal protections are growing. In 2025, Scotland proposed landmark fishing reforms recognizing fishes as sentient, challenging cruel practices like hooking, suffocation, and catch-and-release. New rules would count fishes individually, rather than by weight, and build on the UK’s 2022 Sentience Act—reflecting a shift toward ethical recognition beyond conservation.

Most remarkable and unsettling of all, fishes vilified and eaten by humans suffer just as much as other marine animals we admire. A balanced plant-based diet provides all essential nutrients without harming marine life. Like all land animals, fishes deserve compassion, the right to live in peace, and freedom from exploitation.

Take action to end the most destructive fishing practices.