HERMIT CRABS: SHELL-DWELLERS WITH MOBILE HOMES


Hermit Crab, Abaco Bahamas (Keith Salvesen / Rolling Harbour)

HERMIT CRABS: SHELL-DWELLERS WITH MOBILE HOMES

As everyone knows, Hermit Crabs get their name from the fact that from an early age they borrow empty seashells to live in. As they grow they trade up to a bigger one, leaving their previous home for a smaller crab to move into. It’s a benign** chain of recycling that the original gastropod occupant would no doubt approve of, were it still alive… The crabs are able to adapt their flexible bodies to their chosen shell. Mostly they are to be found in weathered (‘heritage’) rather than newly-empty shells for their home. [**except for fighting over shells] 

Hermit Crab, Abaco Bahamas (Keith Salvesen / Rolling Harbour)

 HERMIT CRAB FACTS TO ENLIVEN YOUR CONVERSATION

  • The crabs are mainly terrestrial, and make their homes in empty gastropod shells
  • Their bodies are soft, making them vulnerable to predation and heat.
  • They are basically naked – the shells protect their bodies & conceal them from predators
  • In that way they differ from other crab species that have hard ‘calcified’ shells / carapaces
  • Ideally the shell should be the right size to retract into completely, with no bits on display

Hermit Crab, Abaco Bahamas (Keith Salvesen / Rolling Harbour)

  • As they grow larger, they have to move into larger and larger shells to hide in
  • As the video below shows wonderfully, they may form queues and upsize in turns
  • Occasionally they make a housing mistake and chose a different home, eg a small tin

Hermit Crab, Abaco Bahamas (Keith Salvesen / Rolling Harbour)

  • The crabs may congregate in large groups which scatter rapidly when they sense danger
  • The demand for suitable shells can be competitive and the cause of inter-crab battles
  • Sometimes two or more will gang up on a rival to prevent its move to a particular shell

HERMIT CRABS CAN EVEN CLIMB TREES – WITH THEIR SHELLS ON TOO

Hermit Crab, Abaco Bahamas (Tom Sheley)

HERMIT CRABS EXCHANGING HOMES with DAVID ATTENBOROUGH

This is a short (c 4 mins) extract from BBC Earth, with David Attenborough explaining about the lives and habits of these little crabs with his usual authoritative care and precision . If you have the time I highly recommend taking a look.

Credits: All photos taken on Abaco by Keith Salvesen except for the tree-climber crab photographed by Tom Sheley; video from BBC Earth

Hermit Crab, Abaco Bahamas (Keith Salvesen / Rolling Harbour)

SHELL HOMES: HERMIT CRABS IN THE BAHAMAS


Hermit Crab ©Melinda Riger @ Grand Bahama Scuba

SHELL HOMES: HERMIT CRABS IN THE BAHAMAS

I’m feeling distinctly crabby right now. In a skilled move that would impress the Bahamas utility providers, the UK’s very own much-vaunted BT selected us for the privilege of being unplugged from the grid last week. From the time of reporting the problem, it has taken them 6 days to plug us back in. It’s a little reminder of the far more persistent Abaco experience! No landline, no wifi, no email for almost a week. To begin with, it was a light relief. After nearly a week, not funny anymore. Here are some nice crabs in conchs to celebrate getting back online while reflecting my crabby mood.Hermit Crab ©Melinda Riger @ G B Scuba Hermit Crab ©Melinda Riger @ GB Scuba copy Hermit Crab ©Melinda Riger @ GB ScubaFind out more about Hermit Crabs – in particular crab racing at Delphi and the intricate rules – here: WACKY RACES AT DELPHIHemit Crab, Delphi (Clare Latimer)

Hermit Crab in a conch ©Melinda Riger @ GB Scuba

Photo credits: all undersea shots – Melinda; potential crab race contestant – Clare