Brown crabs (Cancer pagurus) are widely distributed across the Northeast Atlantic, primarily inhabiting the coastal waters of Europe. These robust crustaceans can be found throughout the North Sea, Irish Sea, English Channel, and extending south along the coast of Portugal. They are a common sight on all coasts around the United Kingdom, from the shallow intertidal zone down to depths of 100 meters.
Geographic Distribution
Brown crabs are prevalent in temperate waters, indicating their preference for specific ocean regions. Their primary geographic range includes:
- North Sea: A rich hunting ground for various marine species, including brown crabs.
- Irish Sea: Known for its diverse marine life and productive fishing grounds.
- English Channel: A busy waterway that also supports a healthy brown crab population.
- Portuguese Coast: Extending their distribution further south along the European Atlantic coastline.
These areas provide the necessary marine conditions and food sources for brown crabs to thrive. For more information on marine ecosystems, you can explore resources from organizations like the Marine Conservation Society.
Preferred Habitats and Depths
Brown crabs are incredibly adaptable, inhabiting a range of underwater environments that offer both shelter and foraging opportunities. Their preferred habitats include:
- Rocky Ground: Particularly favoring areas under boulders where they can hide from predators and ambush prey.
- Mixed Coarse Ground: A combination of sand, gravel, and shell fragments provides good camouflage and digging opportunities.
- Muddy Sand Offshore: In deeper waters, they are often found on softer, muddy substrates, which can be rich in benthic organisms, their primary food source.
| Habitat Type | Key Characteristics | Depth Range |
|---|---|---|
| Rocky Ground | Under boulders, crevices, shelter | Intertidal down to 100m |
| Mixed Coarse Ground | Sand, gravel, shell; good for camouflage | Primarily subtidal, shallower to 100m |
| Muddy Sand Offshore | Softer substrate, rich in benthic prey | Deeper waters, typically 30-100m |
UK Coastal Presence
Around the United Kingdom, brown crabs are ubiquitous. They inhabit virtually all coasts, showcasing their ability to adapt to varying local conditions. Their vertical distribution spans a significant range, from the intertidal zone – the area exposed at low tide – down to depths of 100 meters. This wide depth range allows them to utilize different resources and find suitable conditions as water temperatures and food availability change throughout the year.
Their presence in shallow, rocky intertidal areas makes them accessible for observations during low tide, while commercial fisheries often target them in deeper offshore waters. The robust nature of these crabs and their preferred habitats contribute to their success across such a broad geographical and bathymetric spread. For further details on crab biology, resources like WWF offer insights into marine species.
