 |
|
| hermit crabs text index | photo index |
| Phylum Arthropoda > Subphylum Crustacea > Class Malacostraca > Order Decapoda > Anomurans > hermit crabs |
| Land
hermit crab Coenobita sp. Family Coenobitidae updated Dec 08
Where seen? This large lilac hermit crab is sometimes seen on our undisturbed shores, especially on our offshore islands. But it is only active at night. Features: About 3-6cm. Left pincer usually larger than the right. pincers "squarish" and legs thick. Body and limbs not very hairy. May be brownish to violet and purple. There are two species of land hermit crabs in Singapore. According to the Singapore Red Data Book, Coenobita violascens has "an overall violet colour and especially the fingers of the left claw". It is large and commonly associated with mangrove habitats. The Land hermit crab is so well adapted to life out of water that it will drown if kept underwater! It has special gill chambers that act as lungs. These chambers are large and holds water to keep the gill filaments wet. The hermit crab only needs to occasionally dip in either rainwater or the sea to keep the chambers wet. Females, however, must go to the edge of the sea to release their eggs into the sea. These hatch into planktonic larvae. When the larvae develops into a small hermit crab, it finds an empty shell then heads landward. The Family Coenobitidae includes the largest hermit crab, the Robber or Coconut crab (Birgus latro) which doesn't live in a shell. What does it eat? The hermit crab is a scavenger and may even go far inland to forage. Sometimes, many are seen at night near the visitors' huts on our offshore islands. Possibly looking for scraps left behind by visitors? Shells not enough? Often, those seen are found in shells that are too small for the animal. The poor hermit crab often can't retract all the way into the shell, and a part of it is still sticking out. This is possibly because high up on the shore, there aren't enough empty shells that are suitably large. The lack of suitably large shells on our shores may limit the population of these amazing animals. The land hermit crab is now considered rare on mainland Singapore. Human uses: Hermit crabs have become popular pets and these are usually taken from the wild. Hermit crabs, however, belong in their habitats and not in our homes. More about the impact of keeping hermit crabs as pets. Status and threats: The land hermit crabs are listed as 'Vulnerable' on the Red List of threatened animals of Singapore. Singapore's more accessible beaches are regularly cleaned of any debris that washes up on the high tide mark. But this is where land hermit crabs find shelter, food and new shells. Deprived of their habitat, these endearing animals are no longer commonly encountered on our beaches. According to the Singapore Red Data Book, the many beach improvement schemes, clearance of 'unsightly' natural beach vegetation have almost exterminated these once common animals. due to loss of our natural beaches. Well-intentions beach clean up have also resulted in mass removal of seemingly empty shells containing these animals. |
 Shell is too small! Sentosa, Feb 08  Sisters Islands, Jan 05    |
This hermit crab is seldom seen on the mainland.Land hermit crabs on Singapore shores
 Sentosa, Feb 08 |
 St. John's Island, May 05 |
 Chek Jawa, Jul 02 |
 East Coast, Nov 08 |
 Queueing up to switch shells? |
 |
more photos of land hermit crabs on Singapore shores
part 1 | part 2 | part 3 | part 4
|
Links
|
|
|