Symbiosis Of A Snapping Kind

9:36 PM  , ,  

North-East Coast
Singapore
January 2013

Alpheidae is a family of Snapping Shrimp characterized by having asymmetrical claws, the larger of which is typically capable of producing a loud snapping sound. Other common names of these species include Pistol Shrimp or Alpheid Shrimp. The shrimp are considered to be a major source of noise in the ocean, and can  interfere with sonar and underwater communication when in colonies. (Wow!)
    
A closer look at the Snapping Shrimp. 
Some of the crevices are barely big enough for it to slide out of...

They can be kinda hard to spot as they are often well-hidden with burrows in rocks and on the seabed itself...

Note the little triangular portion on its big claw that appears to be a "fixed back" broken piece? Don't play play, that is the part that snaps shut to cause a loud "Tiak!" sound audible from several metres away. The blast stuns prey like tiny fish and cracks the shells of small clams. It is also used to warn off predators and intimidate rival snapping shrimps.

Merlion Wayfarer spotted two really big ones in a rock pool nearby...

They were of a drab grey colour with one being visibly darker than the other. Were they courting?
    
A small fish was spotted darting around these burrows. Merlion Wayfarer did wonder if these were friends or food...
  
Some Snapping Shrimp species share burrows with Goby fishes in a symbiotic relationship. The burrow is built and tended by the Snapping Shrimp, and the Goby provides protection by watching out for danger. When both are out of the burrow, the Shrimp maintains contact with the Goby using its antenna. The Goby, having the better vision, alerts the Shrimp of danger using a characteristic tail movement, and then both retreat into the safety of the shared burrow.

The symbiotic relationship between the Snapping Shrimp and the Goby (Cryptocentrus Leptocephalus, Slender-Lined Shrimp-Goby) is seen here... 

The Goby hides in the Shrimp's burrow and keeps a look out... 

It exits the burrow and surveys the surroundings with its tail still in the burrow...

A claw is spotted. An unwary observer may think that the poor Goby will soon be the Shrimp's next meal...

When given the go-ahead, the Shrimp slowly comes out of its hiding place... 

It heads straight from some debris outside its doorstep, with its antenna in close contact with the Goby...

Effortlessly it moves a twig half its size with its smaller pincer claw...

That out of the way, it retreats back into its burrow. 
At the same time, its antenna is still in contact with the Goby...
 
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