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Green
seaweed
Division Chlorophyta
updated
Aug 08
if
you learn only 3 things about them ...
Some kinds of green seaweeds are often mistaken for seagrasses.
Many small animals eat green seaweeds.
 'Carpets'
of green seaweed may form on the shores. These may shelter
small animals. Please avoid stepping on the carpet. |
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Where
seen?
Green seaweeds are commonly seen on many of our shores. Some grow
on boulders, coral rubble and other hard surfaces. Others are found
entwined around seagrasses.
Like other seaweeds, some green seaweeds are seasonal (such as sea
lettuce, Ulva sp. or the hairy green
seaweed, Bryopsis sp.). Sometimes one kind of seaweed can
be so abundant that it blankets vast areas of a shore in a green carpet.
A few weeks later, the shore may be bare of this seaweed.
Features: Green seaweeds are,
well, green! They may be grass-green or slightly greyish, but they
are seldom yellowish as some red and brown seaweeds are. Green seaweeds
have similar chlorophyll pigments as those found in land plants. In
fact, it is widely believed that land plants arose from green algae.
Green algae are found in most habitats, not just in the sea. There
are about 8,000 species ranging from microscopic algae (some of which
may be growing on your bathroom walls right now) to delicate freshwater
weeds found in rivers and lakes, and the large green seaweeds in the
sea.
Green seaweeds come in a wide range of shapes: translucent bubbles,
flat sheets, hard flattened coins, bunches of long thin filaments,
bunches of grapes, branched furry stems, coiled strips and more!
Sometimes confused with seagrasses.
Some feathery green seaweeds are also confused for one another. Here's
more on how to tell apart green seaweeds that
look like grapes, and different feathery
green seaweeds and feathery
green seaweeds and seagrasses.
Human uses: Many green seaweeds
are eaten directly by people. In the Philippines, sea
grapes (Caulerpa lentillifera) is cultivated as food and
sold fresh or salted. Some species are used as feritilisers and additives
in animal feed (poultry, cattle, fish).
Unlike brown seaweeds and
red seaweeds, green seaweeds
are not a major source of extracts used commercially.
Role in the habitat: Like other
seaweeds, green seaweeds provide food and shelter for a wide range
of marine animals.
Some of the animals that eat green seaweeds look like the seaweeds!
Those commonly seen include the Ornate
leaf slug (Elysia ornata) and a tiny hairy Bryopsis
slug that is still awaiting identification and is often seen on
the Hairy green seaweed (Bryopsis
sp.) and the tiny Halimeda
slug (Pusilla sp.) often seen on Big
coin green seaweed (Halimeda sp.)
During a seaweed 'bloom' there can be a corresponding explosion in
the number and variety of animals that eat that particular seaweed.
As well as the predators that eat the seaweed-eaters.
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Three different
kinds of green seaweeds
Beting Bronok, Jul 07
This slug looks exactly like the
green seaweed that it probably feeds on
Sentosa, Nov 03
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Division
Chlorophyta recorded for Singapore
Pham,
M. N., H. T. W. Tan, S. Mitrovic & H. H. T. Yeo, 2011. A Checklist
of the Algae of Singapore, 2nd Edition, Oct 2011
+added from our observations.
photo
index of green seaweeds on Singapore shores
Some green seaweeds recorded for Singapore
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Green
seaweeds awaiting identification |
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| Links
References
- Pham, M.
N., H. T. W. Tan, S. Mitrovic & H. H. T. Yeo, 2011. A
Checklist of the Algae of Singapore, 2nd Edition. Raffles
Museum of Biodiversity Research, National University of Singapore,
Singapore. 99 pp. Uploaded 1 October 2011. [PDF, 1.58 MB].
- New records
of marine algae on artificial structures and intertidal flats
in coastal waters of Singapore. A. C. Lee, Lawrence M. Liao and
K. S. Tan. Pp. 5-40. in the Raffles Bulletin of Zoology [pdf,
2.41 MB]
- 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.
- Wee Y.C.
and Peter K. L. Ng. 1994. A First Look at Biodiversity in Singapore.
National Council on the Environment. 163pp.
- Calumpong,
H. P. & Menez, E. G., 1997.Field
Guide to the Common Mangroves, Seagrasses and Algae of the Philippines
 .
Bookmark, Inc., the Philippines. 197 pp.
- Huisman,
John M. 2000. Marine
Plants of Australia
University of Western Australia Press. 300pp.
- Trono, Gavino.
C. Jr., 1997. Field
Guide and Atlas of the Seaweed Resources of the Philippines..
Bookmark, Inc., the Philippines. 306 pp.
- Bell, Peter
R. and Hemsley, Alan R. 2000. Green
Plants: Their Origin and Diversity
2nd edition. Cambridge University Press. 349 pp.
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