learn only 3 things about them ...
You will probably hear one than see one on the shores.
Listen out for them!
The enlarged pincer can be as big as the rest of the shrimp!
a goby share the burrow with the shrimp.
will most likely hear a snapping shrimp before you see one. These
little creatures make the incessant pops that you hear at low tide.
They range from tiny ones to rather large ones that can pack a really
loud pop. They are common on many of our shores, on mudflats, sandy
shores, in seagrass meadows, rocky areas and reefs. But they are often
tucked away in their burrows or other hiding places such as under
rocks, even under carpet anemones and within sponges. Snapping shrimps
forage outside their burrows more actively at night.
are snapping shrimps? Snapping
shrimps are crustaceans that belong
to Family Alpheidae.
Features: 2-7cm long. A snapping
shrimp has one of its pincers greatly enlarged. This pincer may even
be as long as its entire body!
The enlarged pincer can produce a very loud sound. 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.
It crawls slowly on the sea bottom with long walking legs. It can
make a quick getaway by contracting its muscular flexible abdomen
and broad fan-shaped tail. The shrimp has small eyes, which is probably
why some live together with gobies that have much better eyesight
The science of The Sound: A study
of one species of snapping shrimp shows the pincer has a moveable
'finger' held at right angles to a matching 'socket' on the opposite
When the 'finger' is released, it plunges rapidly into the socket,
and an explosive sound results. The
snapping sound is not the result of the finger hitting the socket,
i.e., not like the sound of hands clapping. Rather, a high-speed jet
of water shoots out of the socket due to extremely rapid compression
as the 'finger' plunges into the socket. This jet vapourises the water
and creates large bubbles. The bubbles rapidly collapse (called cavitation),
releasing an extremely loud sound as well as a flash of light, and
for a brief moment, at high temperatures. These findings are possibly
useful for naval applications as the sound of snapping shrimps seriously
interfere with sonar detection in shallow seas. In fact, snapping
shrimps have been studied since World War II as their sounds interfered
with the detection of hostile submarines!
Shrimpy friends: Some species
live in symbiosis with corals, sponges, sea fans and other animals.
The most amazing must be the
relationship between the snapping shrimp and goby. The shrimp
goby lives in the same burrow with a snapping shrimp. With keener
eyesight, the goby keeps a look-out while the shrimp busily digs out
and maintains their shared home. The shrimp is literally constantly
in touch with the goby with at least one of its antennae always on
the goby. When the goby darts into the burrow, the shrimp is right
Colonial shrimps? A kind of snapping
shrimp (Synalpheaus regalis) that lives in sponges in the coral
reefs of Belize were found to form colonies much like termites do.
One 'queen' prawn produces all the members of the colony, which attack
members of other colonies but are peaceful towards members of their
and threats: Most of our snapping shrimps are not listed
among the endangered animals of Singapore, except for the Crinoid
snapping shrimp (Synalpheus stimpsoni).
This tiny shrimp (about 1cm) lives in pairs on feather
stars (crinoids), feeding off the mucus of its host. It is threatened
by reef destruction and siltation.
One pincer greatly enlarged.
Pulau Sekudu, Jun 05
Using the small pincer to carry things.
Labrador, May 02
Sideview of the shrimp
St. John's Island, May 06
This shrimp shares its burrow with a brittle star.
Chek Jawa, Jul 05
shrimps on Singapore shores
Alpheidae recorded for Singapore
Wee Y.C. and Peter K. L. Ng. 1994. A First Look at Biodiversity
*in red are those listed among the threatened
animals of Singapore from Davison, G.W. H. and P. K. L. Ng
and Ho Hua Chew, 2008. The Singapore Red Data Book: Threatened
plants and animals of Singapore.
+from our observation
shrimps seen awaiting identification
Species are difficult to positively identify without
close examination of small features. On this website, they are
grouped by external features for convenience of display.
Alpheus audouini=**Alpheus edwardsii
Alpheus crassimanus=**Alpheus lobidens
Alpheus lutini=**Alpheus obesomanus
Alpheus microrhynchus (EN:
Alpheus ventrosus=**Alpheus lottini
*Athanas japonicus (VU:Vulnerable)
*Potamalpheops amnicus (EN: Endangered)
*Potamalpheops johnsoni (VU: Vulnerable)
*Potamalpheops tigger (VU: Vulnerable)
*Salmoneus singaporensis (CR: Critically endangered)
Synalpheus acanthitelsonis=**Synalpheus hastilicrassus
Synalpheus neomeris=**Synalpheus neomeris
Synalpheus stimpsonii (Crinoid
snapping shrimp) (CR: Critically endangered)
- Michel Versluis,et
al (2000). How
Snapping Shrimp Snap: Through Cavitating bubbles, Science,
289, 2114. DOI:
10.1126/science.289.5487.2114 with a layman's explanation
Shrimp by Kristin Leutwyler on Scientific American.
- D. Lohse,
B. Schmitz & M. Versluis (2001). "Snapping shrimp make flashing
bubbles". Nature 413 (6855): 477-478. DOI:10.1038/35097152.
- Chou, L.
M., 1998. A
Guide to the Coral Reef Life of Singapore. Singapore Science
Centre. 128 pages.
G.W. H. and P. K. L. Ng and Ho Hua Chew, 2008. The Singapore
Red Data Book: Threatened plants and animals of Singapore.
Nature Society (Singapore). 285 pp.
- Lim, S.,
P. Ng, L. Tan, & W. Y. Chin, 1994. Rhythm of the Sea: The Life
and Times of Labrador Beach. Division of Biology, School of
Science, Nanyang Technological University & Department of Zoology,
the National University of Singapore. 160 pp.
- Jones Diana
S. and Gary J. Morgan, 2002. A Field Guide to Crustaceans of
Australian Waters. Reed New Holland. 224 pp