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Fiddler Crab

Fiddler Crab
Photo Information
Copyright: jitti coowanitwong (jcoowanitwong) Gold Star Critiquer/Gold Note Writer [C: 1679 W: 0 N: 3120] (13754)
Genre: Animals
Medium: Color
Date Taken: 2006-12-30
Categories: Crustacia
Camera: canon s3 is
Exposure: f/4.5, 1/100 seconds
Photo Version: Original Version
Date Submitted: 2007-01-02 21:40
Viewed: 4245
Points: 14
[Note Guidelines] Photographer's Note
I was on walkway above muddy beach. These fiddler crabs are so tiny. The hole in front of the crab is the burrow or home of this crab. (Jan. 3, 2007)

Phylum: Arthropoda
Subphylum: Crustacea
Class: Malacostraca
Order: Decapoda
Family: Ocypodidae
Genus: Uca
Subgenus: Gelasimus Species: Uca vocans Sp.

A fiddler crab, or calling crab, may be any of approximately 97 species of semi-terrestrial marine crabs of the genus Uca. Fiddler crabs are closely related to the ghost crabs - genus Ocypode.
Found in mangroves and on sandy or muddy beaches. Fiddler crabs are easily recognized by their asymmetric claws. It is the males which boast an oversized claw or cheliped; it plays a role in courtship and signalling among conspecifics. The movement of the smaller claw from ground to mouth during feeding inspired the crabs' common name; it appears as if the animal is playing the larger claw like a fiddle.
Reaching a diameter of between 2 and 4½ cm (1–2 inches), fiddler crabs may be tan, blue-green, turquoise, black, yellow, or orange in colour. Diurnal animals, fiddler crabs are actually a darker colour by day than they are by night. They are an important source of food for shore birds and other animals inhabiting salt marshes. The crabs make burrows up to 60 cm (23 inches) deep in the muddy substrate to which they retreat during high tides. When the tide is out, fiddler crabs tirelessly scurry sideways along the beach as they comb the sands for food.
The crab's smaller claw picks up a chunk of sediment and brings it to the mouth, where its contents are sifted through. After anything edible is salvaged, be it algae, microbes, fungus, or other decaying detritus, the sediment is replaced in the form of a little ball. The presence of these sediment balls near the entrance to a burrow is a good indication of its occupation. Some experts believe that the feeding habits of fiddler crabs play a vital role in the preservation of wetland environments; by sifting through the sands, they aerate the substrate and prevent anaerobic conditions.
Fiddler crabs live rather brief lives of no more than two years. During courtship, the males wave their oversized claws high in the air and tap them on the ground in an effort to attract females. Fights between other males will also occur, which are presumably meant to impress the females; if a male loses his larger claw, the smaller one will grow larger and the lost claw will regenerate into a new (small) claw. For some species of fiddler crabs,the small claw remains small, while the larger claw regenerates over a period of several molts, being about half its former size after the first molt.
The female fiddler carries her eggs in a mass on the underside of her body. She remains in her burrow during a two week gestation period, after which she ventures out to release her eggs into the receding tide. The larvae remain planktonic for a further two weeks.


blakitan, elefantino, Alex99, marhowie, jmp has marked this note useful
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Critiques [Translate]

You should of zoomed in more on the crab in my oppinion so we could see the crab bigger.
The crab is kind of small in this picture so the detail of the crab is small.
Nice crab,

Hi Jitti,
This one is a bit too small to be able to see the crab. I guess that you could not get any closer since this was a muddy soil.

Ben Lakitan

Nice crab, a new one for me!

  • Great 
  • Alex99 Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 4072 W: 133 N: 7096] (23735)
  • [2007-01-03 7:08]

Hi Jitti.
First of all my best wishes in 2007 and many nice shots.
I think your cropping has some sense. It allows to see the environment where the crab is inhabited. At whole the shot is well detailed, coloured and exposed. Cockleshells well decorate the captured scene.
My best regards and TFS.

  • Great 
  • magal Gold Star Critiquer/Gold Note Writer [C: 224 W: 0 N: 313] (1251)
  • [2007-01-03 9:35]

Hi Jitti,
First of all my friend, my best wishes for the new year!!
I think that this shot tends to be a bit misleading. The composition is simple but very effective in showing the crab's habitat. It has to be seen in that perspective [IMMO] and in that respect it is very successful. Closer focussing would yes bring more detail on the crab but it would also miss the subject here presented.
I personally like this POV and particularly like that subtle diagonal shaft of light that so effectively adds more substance to the whole composition.
Well seen and captured Jitti, TFS

Good detail and composition Jitti.
I think a bit closer would be better.
Still a nice post and excellent notes on the fiddler crab :)
Have a Great Day!

Hello Jitti,
I have to agree with Howard that it is a little far but details, composition and POV are good anyway. I just wish it could have been a little closer. This is a very interesting capture with great notes. TFS,

  • Great 
  • jmp Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 1659 W: 95 N: 2273] (8415)
  • [2007-01-03 17:30]

Hi Jitti,
Very good sharpness, details and colors and excellent notes. I agree with Howard about a closer view of the crab.
Best regard, José m.

Hola Jitti,
Curiosa y didáctica toma, aunque me hubiese gustado verla mas cerca. Un cordial saludo

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