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Haddon's
carpet anemone
Stichodactyla haddoni
Family Stichodactylidae
updated
Nov 2019
if you
learn only 3 things about them ...
Small carpet anemones may be hidden under seaweed. Don't
step on them!
You may touch them gently, but please don't poke them.
Please
don't feed the anemone or 'rescue' any of its prey |
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Where
seen? This enormous anemone bigger than your face is commonly seen on many
of shores. In sandy areas, among seagrasses and also on coral rubble.
Features: Diameter 40-50cm when
fully expanded, but is said to reach up to 75-80cm. The large oral
disk is densely covered with short tentacles so that it resembles
a short-pile carpet. Tentacles short, stubby and may have bulbous
tips, sometimes resembling beads. Tentacles are sticky. The outer
edge of the oral disk is fringed with tentacles that are twice as
long (exocoelic tentacles), alternating with short ones (endocoelic
tentacles). The long body column is usually buried and ends in a pedal
disk that anchors the animal. Small bumps (verrucae) on the body column
are non-adhesive, small and not visible as they are usually the same
colour as the body colum. |
Chek Jawa, Jun 05
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Verrucae invisible.
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Distinctive alternating 'long' and 'short'
tentacles at the circumference.
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Cyrene, Mar 07
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Pulau Sekudu, Feb 07
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Chek Jawa, Jun 05
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Stinging carpet! Like other
anemones, the carpet anemone has stingers in its tentacles. Generally,
these stings do not hurt human beings, but they can leave welts on
sensitive skin.
Carpet food: Carpet anemones
harbour symbiotic single-celled algae (called zooxanthellae). The
algae undergo photosynthesis to produce food from sunlight. The food
produced is shared with the anemone, which in return provides
the algae with shelter and minerals. The zooxanthellae are believed
to give the tentacles their brown or greenish tinge. Carpet anemones
may also feed on fine particles that are trapped on their bodies.
The anemones have also been seen swallowing various animals. The sticky
tentacles grab any that blunder or are washed into them. The oral
disk can contract quickly to hold on to the luckless prey, which is
eventually transferred into the central mouth. Some large creatures
that are swallowed up by carpet anemones include fishes and crabs.
More photos of what our carpet anemones have
been seen swallowing.
Haddoni friends: Besides the symbiotic
algae that lives inside the their tentacles several kinds of animals
have been recorded elsewhere as being associated with Haddon's carpet
anemones. These include anemone shrimps (Periclimenes sp.),
and fishes such as Dascyllus trimaculatus and anemonefishes (Amphiprion sp.) including A. akindynos, A. clarkii, A.
fuscocaudatus, A. polymnus, A. sebae, A. xanthurus. But so far,
the only animals seen living on our Haddon's carpet anemones are the tiny carpet
anemoneshrimp (Periclimenes sp.), Peacock-tail anemone shrimp (Periclimenes brevicarpalis).
Other animals have been observed taking shelter under these anemones,
such as crabs and snapping shrimps. Ball
sea cucumbers are often found buried near carpet anemones. Also
seen were Kite
butterflyfish (Parachaetodon ocellatus) and Chequered
cardinalfish (Apogon margaritophorus) swimming near, but
not touching, carpet anemones. Sometimes small groups of small Kite
butterflyfishes are seen near carpet anemones. |
Capturing small fishes by folding
the oral disk over the prey.
Chek Jawa, Feb 02 |
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Peacock-tail anemone
shrimps
are often
found in these anemones.
Kusu Island, Jul 04 |
Should I 'save' animals trapped in a carpet
anemone? If you do, you will be depriving the anemone of
a meal. It might not get so lucky again for a while. The animal that
you 'saved' might also not survive if it was badly stung by the carpet
anemone.
Should I feed the anemones? Please
don't. Carpet anemones know how to feed themselves. You might hurt
the anemone if you put the wrong thing on it. If you put another living
animal on an anemone you will be hurting two animals. Please don't
put objects such as litter or dead crabs on a carpet anemone either. |
Some carpet anemones
out on the hot dry sand bar at low tide.
Chek Jawa, Feb 02 |
They can survive out of water for a
short time by shrinking their oral disk.
Chek Jawa, Feb 02 |
They can also tuck the oral disk
into the body column.
Chek Jawa, May 03 |
Carpet of Death: On Chek Jawa,
you might notice that there are many carpet anemones on the hot, dry
sand bar at low tide. Why are they there when they could be in the
cool pools instead? On Chek Jawa, the sand bar is the first to emerge
at low tide and the last to submerge as the tide comes in. As fishes
and other animals enter the lagoon with the incoming tide, or leave
with the outgoing tide, they have to negotiate this minefield of anemones.
Some unlucky creatures might blunder into a Carpet anemone. Carpet
anemones on the sand bar may thus have a better chance of a meal.
High and dry: Carpet anemones
can survive for a short while out of water. To conserve water, the
oral disk shrinks to reduce the surface area and mucus is secreted
to cover the mouth and delicate body parts. Sediment gets stuck to
this mucus, probably providing some shade from the sun. Smaller anemones
may also tuck the oral disk into the body column at low tide. When
the tide comes back, the oral disk furls to the full size. |
An uprooted and upside down anemone
which is otherwise healthy.
Chek Jawa, Nov 06 |
Bleaching and ballooning
due to prolonged extreme fall in salinity.
Chek Jawa, Jan 07 |
Bleaching and exploded anemone
due to prolonged extreme fall in salinity.
Chek Jawa, Jan 07 |
Can carpet anemones move? Carpet
anemones probably usually stay in one spot. However, they can uproot
themselves and move to a new place. This is probably how they avoid
being buried as the sand bar shifts. If you find an 'uprooted' carpet
anemone, you may place it in a pool of water. There is no need to
're-plant' it.
Bleaching carpet anemones: Carpet
anemones do suffer from bleaching, turning pale or flourescent colours when the symbiotic algae leave them. This happens when they are stressed. Stresses include elevated seawater temperatures for an extended time (which causes mass coral bleaching). As well as other extreme changes in water conditions due to pollution or other causes. In 2007, there was mass bleaching of carpet anemones on Chek Jawa, believed to be due to prolonged and high rain fall upstream in the Johor River. The exreme and prolonged fall in salinity caused the carpet anemones to not only bleach but also balloon up and explode.
Carpet babies: There is not much
information on how Carpet anemones reproduce. Small carpet anemones
seen on our shores may actually be another species, the Mini
carpet anemone (Stichodactyla tapetum) and not a young
version of the Haddon's carpet anemone.
Human uses: Unfortunately, these
anemones are harvested for the live aquarium trade. Like other animals
harvested for the live aquarium trade, most die before they can reach
the retailers. Without professional care, most die soon after they
are sold. Those that do survive are unlikely to breed successfully. |
Haddon's
carpet anemones on Singapore shores |
Other sightings on Singapore shores |
Pasir Ris-Loyang, Oct 20
Photo
shared by Loh Kok Sheng on facebook. |
East Coast, May 08
Photo
shared by Loh Kok Sheng on his
blog. |
East Coast-Marina Bay, Jan 21
Photo
shared by Vincent Choo on facebook. |
Labrador, Aug 17
Photo
shared by Loh Kok Sheng on facebook. |
Sentosa Serapong, Jul 15
Photo
shared by Loh Kok Sheng on flickr. |
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St. John's Island, Sep 07
Photo
shared by Loh Kok Sheng on his
blog. |
Terumbu Pempang
Laut, Apr 11
Photo shared by Loh Kok Sheng on his
blog. |
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Pulau Senang, Aug 10
Photo
shared by Loh Kok Sheng on his
flickr. |
Pulau Pawai, Dec 09
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Pulau Pawai, Dec 09 |
Links
References
- Daphne Gail
Fautin, S. H. Tan and Ria Tan. 30 Dec 2009. Sea anemones (Cnidaria:
Actiniaria) of Singapore: abundant and well-known shallow-water
species. Raffles Bulletin of Zoology Supplement No. 22: 121-143.
- Chou, L.
M., 1998. A Guide to the Coral Reef life of Singapore.
Singapore Science Centre. 128 pages
- Erhardt,
Harry and Daniel Knop. 2005. Corals:
Indo-Pacific Field Guide
IKAN-Unterwasserachiv, Frankfurt. 305 pp.
- Gosliner,
Terrence M., David W. Behrens and Gary C. Williams. 1996. Coral
Reef Animals of the Indo-Pacific: Animal life from Africa to Hawaii exclusive of the vertebrates
Sea Challengers. 314pp.
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