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What Crabs??

What Crabs??
Photo Information
Copyright: James Parker (Jamesp) Gold Star Critiquer/Gold Note Writer [C: 1369 W: 9 N: 6334] (18906)
Genre: Animals
Medium: Color
Date Taken: 2006-04-22
Categories: Crustacia, Rain Forest
Camera: Canon EOS 1Ds MkII, Canon 24-70 mm f 2,8 L-USM
Exposure: f/2.8, 1/60 seconds
More Photo Info: [view]
Photo Version: Original Version
Theme(s): Christmas Island [view contributor(s)]
Date Submitted: 2010-02-04 8:16
Viewed: 5224
Points: 26
[Note Guidelines] Photographer's Note
This posting is more to show TN-ers what the floor of the Christmas Island Rainforest looks like - it is not great quality and because of the very small plane and 5 hour flight from the mainland, I didn't even have a monopod.

I was actually worried we wouldn't see any crabs!!!! We saw millions!

The most obvious thing (apart from the crabs) is the lack of leaf letter - when a leaf falls, all the nearby crabs scuttle to it and fight over it, The proud winner takes the leaf down its burrow. The crabs will grab anything - we almost lost a sunglasses case and a camera case - we saw them bobbing along the forest floor.

The crabs congregate in the shadier areas to prevent dehydration. I posted a lone crab crossing the Phosphate road some time ago "http://www.treknature.com/gallery/photo96161.htm" - please check it out for a clearer view of this species.

The Christmas Island red crab, Gecarcoidea natalis, is a species of terrestrial crab endemic to Christmas Island in the Indian Ocean. Although restricted to a relatively small area, it is estimated that up to 120 million red crabs may live there, making it the most abundant of the 14 terrestrial crab species on Christmas Island . The crabs eat mostly fallen leaves and flowers, but will occasionally eat other animals, including other red crabs if the opportunity arises.

The carapace is up to 116 mm long, rounded, and encloses the gills. The claws are usually of equal size, unless one becomes injured or detached, in which case the limb will regenerate. During that time, it will be the smaller of the two. The male crabs are generally larger than the females, while adult females have a much broader abdomen and usually have smaller claws. The broader abdomen of the female Christmas Island red crab only becomes apparent in the third year of growth.

Christmas red crabs live in burrows, in order to shelter from the sun. Since they still breathe through gills, the possibility of drying out is a great danger for them. They are famous for their annual migration to the sea in order to lay their eggs in the ocean. During the migration, the crabs cover the highway routes to the coast so densely that they can be seen from the air. Volunteers shovel the crabs off the roads and, although no harm is intended, some of the countless millions of crabs inevitably get injured - there are also to crab bridges - the sides of the phosphate road are borded off and the crabs move along to structures where they can climb up and over the road easil..

Early inhabitants of Christmas Island hardly ever mentioned these crabs. It is possible that their famous large population size was caused by the extinction of the endemic Maclear's Rat, Rattus macleari in 1903, which may have kept the crab's population in control.

An exploding population of the yellow crazy ant, an invasive species accidentally introduced to Christmas Island and Australia from Africa, is believed to have killed 15–20 million red crabs in recent years.

Hormon_Manyer, horias, nglen, siggi, CeltickRanger, boreocypriensis, tuslaw, anemone, maurydv, nasokoun, uleko has marked this note useful
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Critiques [Translate]

Hi James,
Very interesting to see a forest without leaf letter. And also very interesting to see those crabs (everywhere on the ground). Surely not the most brilliant photo technically, but even a humorous one with all those crabs around. The useful note adds a great plus, thanx James.
Best regards from Hungary, László

  • Great 
  • horias Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 837 W: 58 N: 2084] (11033)
  • [2010-02-04 8:24]

Hello James
Wonderful capture!
How many crabs!
I am so glad to see that!

  • Great 
  • PeterZ Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 5137 W: 166 N: 13121] (49139)
  • [2010-02-04 8:41]

Hello neighbour James,
On television I saw a film about this phenomenon on Christmas Island. Very impressive. Excellent photo in very good natural colours and sharpness.

  • Great 
  • nglen Gold Star Critiquer/Silver Workshop Editor/Gold Note Writer [C: 2883 W: 30 N: 9683] (36145)
  • [2010-02-04 10:35]

Hi James. It looks as if the Red Craba were every where. I see what you mean about the ground being so poor . I would think its an unusual sight se all the crabs around. Well taken TFS.

  • Great 
  • siggi Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 3097 W: 109 N: 12399] (52850)
  • [2010-02-04 12:04]

Hello James,
great shot and clarity photo. Excellent sharpness and nature colours. Wonderful moment TFS. Best Regards

hello James

j'aurais eu peur pour mes pieds, excellent photo of Rain Forest nature,
with very fine POV & DOF, fine focus sharpness and details, TFS


Hi Bro James,

Great capture of these red craps under forest showing their beahaviour on congregating in the shady areas to prevent dehydration. TFS this educative shot MF!
Have a nice night and WE!


  • Great 
  • tuslaw Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 2754 W: 282 N: 4931] (19883)
  • [2010-02-04 19:21]

Hello James,
Even though your main intent was to show the forest floor, I think this is a wonderful image showing this large population of Red Crabs.
I have seen documentaries on National Geographic channel of this event, but it is even more exciting seeing a shot from a fellow TNer.
You have captured excellent detail even without a monopod, and the colors are very natural and beautiful. Nicely composed with just the right exposure!!

Hi James.
Wonderful photo of these red crabs under shadow wit clear details and fine composition. Great notes as always.
TFS and kind regards,

Hello James,
a very interesting picture and notes about these Crabs, very good sharpness and splendid natural colours.
Best regards

hello James,
this is a very interesting scene, it should it is a very good experience this place, it's a good composition from this POV, a fine photo output!
keep photographing! TFS

Ciao James, fantastic capture of a lot of crab spider, splendid natural colors in a wonderful forest, very well done, ciao Silvio

  • Great 
  • uleko Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 3396 W: 172 N: 3310] (10940)
  • [2010-02-06 7:50]

Hello James,
Amazing to see all these little Crabs covering the ground like Ants! I'd be so afraid of stepping on them. An interesting scene very well captured.
Many thanks and regards, Ulla

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