Crabs are among the most misunderstood and exploited marine animals. While they have existed for over 200 million years, dating back to the Jurassic period, humans have subjected them to immense cruelty, treating them as mere commodities. This page explores their natural lives, the various ways they are used and killed, and how we can help protect them.

Crabs in the Wild

Crabs belong to the infraorder Brachyura and are found in nearly every marine environment, from tropical coral reefs to the deep sea and even on land. With over 6,800 species, their adaptations are diverse and fascinating.

Fascinating Facts

Communication: Crabs communicate by drumming and waving their pincers. For example, male fiddler crabs wave their enlarged claws to attract females.

Intelligence: Studies have shown that crabs can learn to navigate mazes and remember routes, indicating a level of spatial awareness and memory.

Longevity: Japanese spider crabs can live for up to 100 years in their natural habitat.

Shell Trading: Hermit crabs engage in social behaviors, forming "vacancy chains" where multiple individuals line up and exchange shells to find the best fit.

Size Extremes: The smallest known crab, the pea crab (Pinnothera faba), measures about half an inch across, while the largest, the Japanese spider crab (Macrocheira kaempferi), can have a leg span exceeding 13 feet (4 meters).

Natural Diet and Predators

Most crabs are omnivorous, feeding on algae, plankton, mollusks, and detritus. They play a crucial role in the ecosystem by recycling nutrients and maintaining the health of their habitats. Predators of crabs include birds, fish, octopuses, and even other crabs.

Crabs and Sentience

Scientific research indicates that crabs possess complex nervous systems capable of processing pain. Studies have demonstrated that crabs exhibit behavioral and physiological responses consistent with the experience of pain. In 2022, the UK recognized decapod crustaceans, including crabs, as sentient beings under the Animal Welfare (Sentience) Act.

The Exploitation of Crabs

Crabs are exploited on a massive scale, from commercial fishing and farming to their use in cosmetics and the pet trade.

Crab Fishing and Farming

The majority of crabs consumed globally are wild-caught using methods such as:

Crab Pots: Baited traps that capture crabs alive. Crabs can remain confined for extended periods, leading to stress and injury.

Trawling: Dragging weighted nets across the seabed, which can cause habitat destruction and result in high bycatch rates, affecting non-target species.

In 2018, over 35,000 tonnes of crabs were landed by UK fishing vessels. While aquaculture of crabs is less common than wild capture, there is a growing interest in farming certain species.

Live Transport

To meet consumer demand for fresh seafood, crabs are often transported live under conditions that can cause significant suffering:

Claw Binding: To prevent injury to handlers and other crabs, claws are often bound, restricting natural behaviors.

Overcrowding: Crabs are packed tightly, leading to physical injuries and increased aggression.

Prolonged Deprivation: During transport, crabs may be deprived of food and water, leading to further stress and potential mortality.

Killing Methods

Common methods of killing crabs include:

Boiling Alive: A traditional practice that causes significant pain, as crabs possess the neurological capacity to experience it.

Chilling or Freezing: Intended to numb the crabs before killing.

Dismemberment: Some practices involve dismembering crabs while they are still conscious, leading to severe pain and distress.

Crabs in the Cosmetics and Pharmaceutical Industries

Crabs are utilized in various industries beyond food:

Chitosan Production: Derived from crab shells, chitosan is used in products like wound dressings, water purification, and dietary supplements.

Horseshoe Crab Blood: While not true crabs, horseshoe crabs are used for their blue blood, which contains amebocytes used in medical testing

Crabs in the Pet Trade

Inadequate Environments: Lack of proper substrates, humidity, and space can lead to health issues, including dehydration, stress, and improper molting.

Social Isolation: Hermit crabs are highly social animals, yet they are often kept alone in captivity, which negatively impacts their well-being.

High Mortality Rates: Many hermit crabs die prematurely in captivity due to poor care, unsuitable habitats, and stress from capture and transport.