updated Mar 14
learn only 3 things about them ...
This seagrass is rarely seen on our shores.
It doesn't flower frequently, and the flowers are complex.
is eaten by dugongs.
This seagrass is abundant on Pulau Semakau, growing among the more
dominant Tape seagrass (Enhalus acoroides),
and on Cyrene Reef.
Noodle seagrass is found throughout the tropical Indo-West Pacific
region. Elsewhere, it can form thick tall stands without any other
seagrass species. It can also grow among other seagrasses species,
where it is then smaller. It is rarely found in shallow intertidal
areas. It appears to respond rapidly to increased nutrient availability.
Features: Leaves of those
seen were 5-10cm long, but elsewhere, they can grow to 50cm long.
The seagrass has tubular leaves much like a thick noodle! Unlike other
seagrasses that are flat, noodle seagrass is circular in cross-section.
The leaves have a smooth pointed tip. The rhizomes (underground stems)
are slender (1.5mm in diameter). Shoots emerge from these rhizomes,
each shoot with 2-3 leaves, the lower portions encased in a sheath.
Longer shoots tend to be branched and found in calmer waters. As the
leaves contain air cavities, they float easily when detached. Older
leaves tend to break off as they become brittle. Elsewhere, these
may form dense rafts that float and wash ashore.
Sometimes confused with Needle
seagrass (Halodule sp.). While both are long and narrow,
noodle seagrass, however, is cylindrical like plastic tubing or noodles,
while needle seagrass is flat like a ribbon.
Flowers and fruits: Noodle seagrass
has separate male and female plants. The flowers form a complex inflorescence
(called a cyme). Each flower forms in a branching array on a stem.
The fruit forms a small nut that is hard and beaked. An inflorescence
with mature seeds may break off and float away some distance.
in the habitat: Dugongs graze on this seagrass where there
are no Halophila or Halodule seagrasses available. So
it is also sometimes called Dugong grass.
and threats: It is listed as 'Endangered' on the Red List
of threatened plants of Singapore.
Pulau Semakau, Mar 05
Pulau Semakau, Jun 05
Pulau Semakau, Jun 05
Terumbu Semakau, May 10
Cyrene Reef, Oct 08
Cyrene Reef, Aug 11
seagrass on Singapore shores
L.J., Yaakub, S.M., and Yoshida, R.L. (2007). Seagrass-Watch:
Guidelines for TeamSeagrass Singapore Participants (PDF).
Proceedings of a training workshop, National Parks Board, Biodiversity
Centre, Singapore, 24th-25th March 2007 (DPI&F, Cairns). 32pp.
seagrasses on the Seagrass-Watch website.
Michelle (et. al). 2004. A Guide to Tropical Seagrasses of
the Indo-West Pacific. 2004. James Cook University. 72 pp.
H. P. & Menez, E. G., 1997.Field
Guide to the Common Mangroves, Seagrasses and Algae of the Philippines.
Bookmark, Inc., the Philippines. 197 pp.
- Hsuan Keng,
S.C. Chin and H. T. W. Tan.1998, The
Concise Flora of Singapore II: Monoctyledons
Singapore University Press. 215 pp.
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.