> Subphylum Vertebrate > fishes
learn only 3 things about them ...
Often mistaken for snakes, they are fish! They breathe
They have smooth skin instead of scales.
have strong jaws with sharp teeth. Don't touch them!
mistaken for snakes, these large wriggly fishes are occasionally seen
on our shores. Moray eels are secretive fishes and usually seen only
at night and in the more undisturbed shores with reefs and coral rubble.
Sightings are usually brief as the fish disappears quickly into some
crevice or hiding place.
What are moray eels? Moray eels
belong to the Family Muraenidae. According to FishBase:
the family has 15 genera and 200 species. They are found worldwide
in both tropical and temperate seas.
Features: Moray eels are extremely
long fishes with muscular bodies. Their bodies are compressed sideways
(they are not tubular). They have no pelvic or pectoral fins. The
dorsal and anal fins extend over the entire length of the long body
and are continuous with the tail fin, resulting in the typical eel-like
profile. Instead of scales, they have thick, smooth skin. The large,
strong jaws are filled with lots of teeth. The eyes are small. They
have a pair of tubular nostrils at the tip of the snout, and small
circular gill openings. Eels swim by moving their muscular bodies
in S-shapes, rather like a snake.
Sometimes mistaken for
snakes. Here's more on how
to tell apart sea snakes, eels and eel-like animals.
What do they eat? Moray eels'
prey include fishes, crustaceans, snails and octopus,
squid and cuttlefish. Those that eat fish have sharp, long, fang-like
teeth to grab and hold on to their slippery prey. Those that eat hard-shelled
crabs and snails have pebble-like teeth to crush prey.
Two sets of jaws! A moray eel
has a special trick up its throat to help it swallow prey. Lots of
fish have a second set of jaws, but these tend to be hard grinding
plates or jaws with little teeth that don't move much. The moray eel's
second set of jaws, on the other hand, is armed with large, curved
teeth and powered by elongated muscles that allow for extreme mobility.
These reach forward to seize and drag prey into the eel's throat.
Eels with razor sharp teeth and powerful bites can cause serious lacerations
that are prone to infection because of the bacteria in their mouth.
But their reputation as vicious beasts is undeserved. Moray eels are
usually docile. Like other wild animals, they will bite only if provoked.
Human uses: Some species are havested
for the aquarium trade. Some species have poisonous flesh which causes
ciguatera poisoning and should thus not be eaten.
Status and threats: Moray eels
are not listed among the threatened animals of Singapore. However,
like other fish and creatures harvested from the wild, 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.
Like other creatures of the intertidal zone, they are affected by
human activities such as reclamation and pollution. Over-collection
can also have an impact on local populations.
A fierce predator!
eels on Singapore shores
Muraenidae recorded for Singapore
Wee Y.C. and Peter K. L. Ng. 1994. A First Look at Biodiversity
*Lim, Kelvin K. P. and Jeffrey K. Y. Low, 1998. A Guide to the Common
Marine Fishes of Singapore.
Gymnothorax boschii=**Echidna nebulosa
*Gymnothorax reevesii (Brown-spotted
Gymnothorax tile (Estuarine moray
Uropterygius concolor (Brown
- Wee Y.C.
and Peter K. L. Ng. 1994. A First Look at Biodiversity in Singapore.
National Council on the Environment. 163pp.
- Allen, Gerry,
Fishes of South-East Asia: A Field Guide for Anglers and Divers.
Periplus Editions. 292 pp.
- Kuiter, Rudie
H. 2002. Guide
to Sea Fishes of Australia: A Comprehensive Reference for Divers
New Holland Publishers. 434pp.
Ewald and Robert Myers. 2001. Coral
Reef Fishes of the World
Periplus Editions. 400pp.