Silver Moony (Monodactylus argenteus)

Silver Moony (Monodactylus argenteus)

A juvenile Silver Moony found in a pontoon. (Photography by: Lumin Ong)

Family: Monodactylidae
Species Name: Monodactylus argenteus
Common Name(s): Silver Moony, Diamondfish, Mono

Presence in Singapore: Native
Habitat: Coastal such as mangrove estuaries, tidal rivers and shallow reefs. Occasionally seen in lower freshwater stretches.
Conservation status: Near Threatened (Red Data Book 3)

The Silver Moony is a popular fish in the aquarium trade, especially for brackish aquariums but however, it is often advertised as a purely freshwater fish which isn't true. Being a euryhaline fish, the Silver Moony is relatively common in our coastal habitats ranging from brackish mangrove swamps to saltwater ones such as along seawalls, and in shallow reefs. 

Adult Silver Moonies can reach a maximum known length of 27cm but are usually half that size. Juveniles are more common in the upper reaches of their habitats while adults stay more at the coast. This is a unique-looking fish, being shaped like a diamond as its common name suggests with yellow fins standing out along its silver body. Very young juveniles are dark with orange fins.

They are known to form large schools but juveniles are usually solitary or found with a few other individuals. This fish is omnivorous, feeding on plankton, detritus and other small mid-water edibles. Interestingly, the juveniles are known to approach similar-sized and larger fishes in an attempt to "clean" them but are often met with annoyance.

A trio of very young Silver moonies.

A juvenile Silver Moony attempting to "clean" a Mangrove Cardinalfish.

References

• FishBase. Monodactylus argenteus (Linnaeus, 1758) – Silver Moony. Retrieved from https://www.fishbase.se/summary/Monodactylus-argenteus.
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.

 

Green Spotted Pufferfish (Dichotomyctere nigrovidis)

 Green Spotted Pufferfish (Dichotomyctere nigroviridis)

A Green Spotted Pufferfish at Admiralty Park during high tide. (Photograph by: Lumin Ong)

Family: Tetraodontidae
Species Name: Dichotomyctere nigroviridis
Common Name(s): Green Spotted Pufferfish

Presence in Singapore: Native
Habitat: Estuarine such as in mangrove swamps. Enters freshwater rivers and streams etc.
Conservation status: Least Concern (Red Data Book 3)

The Green Spotted Pufferfish is probably the most commonly seen pufferfish in Singapore as it is abundant in our mangrove habitats, which it enters during a rising tide. It is also a popular aquarium fish, where they're sold as freshwater fishes when they thrive much better in more saline waters. This pufferfish can grow up to 17cm but are usually seen at half that size. It is unique looking among its kind in Singapore, making it easy to identify thanks to its colouration and patternings.

Like all pufferfishes, the Green Spotted Pufferfish is mostly a hunter of hard-shelled invertebrates, which it uses its beak-like teeth to crush. It is not picky however and will even go for other fishes. When threatened by potential predators, they will puff up by inhaling water, revealing small spines all over the body in the process. Green Spotted Pufferfishes also contain the deadly tetrodotoxin which can kill if the fish is consumed.

A juvenile Green Spotted Pufferfish at the surface in Sungei Buloh Wetland Reserve.

References

• FishBase. Dichotomyctere nigroviridis (Marion de Procé, 1822) – Spotted Green Pufferfish. Retrieved from https://fishbase.se/summary/7763.
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.

Barramundi (Lates calcarifer)

Barramundi (Lates calcarifer)

A medium-sized Barramundi found patrolling in the shallow waters at Eagle Point.

Family: Latidae
Species Name: Lates calcarifer
Common Name(s): Barramundi, Asian Sea Bass, Giant Sea Perch

Presence in Singapore: Native
Habitat: Varied. Ranges from freshwater rivers to coastal habitats such as lagoons.
Conservation status: Data Deficient (Red Data Book 3), Least Concern (IUCN)

A fish most people should know, be it by name and/or taste. In Singapore, the Barramundi can be found in a variety of habitats with varying salinity such as lagoons, estuaries, freshwater and tidal rivers. The Barramundi is a large, predatory fish that have reached lengths of up to two meters on record. It hunts near the bottom for smaller fishes, crustaceans and molluscs as adults while the juveniles feed on zooplankton. It is a highly recognizable fish with its elongated body and sloping head, usually clad in grey of varying darkness. 

Adult Barramundi that usually reside in the upper reaches of freshwater habitats such as rivers migrate down to estuaries to breed. The juveniles then mature in coastal habitats such as mangrove swamps before repeating the cycle. Populations of Barramundi are known to establish in saltwater as well.

The Barramundi is an important food fish world wide and are raised in aquaculture across many countries including Singapore. It is also a popular sport fish due to the fight it's able to give anglers.

References

• FishBase. Lates calcarifer (Bloch, 1790) – Barramundi. Retrieved from https://www.fishbase.se/summary/Lates-calcarifer.html.
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.

Indian Mud Moray (Gymnothorax tile)

 Indian Mud Moray (Gymnothorax tile)

An Indian Mud Moray found at the side of a tidal river during an upset in water chemistry.

Family: Muraenidae
Species Name: Gymnothorax tile
Common Name(s): Indian Mud Moray

Presence in Singapore: Native
Habitat: Muddy estuaries, mangrove swamps, river mouths.
Conservation status: Least Concern (Red Data Book 3)

This moray eel is abundant in our estuaries but in true moray eel fashion, it is tough to find due to its elusive nature and that their habitats are usually muddy. Due to its euryhaline nature, it is often sold as a freshwater in the aquarium trade but it thrives much better and longer in brackish water. Growing to a length of 60cm, the Indian Mud Moray preys on other fishes and crustaceans which it uses its strong sense of smell to locate, making up for their poor eyesight. It also has a recognizable look among local moray eels, exhibiting a dirty brown base colour with tiny, yellow speckles.

Like all moray eels, the Indian Mud Moray possesses two sets of jaws: 1. the oral jaw which is used to do the initial grasping of prey and 2. a pharyngeal jaw resting inside that helps to pull the prey in or tear off chunks. 

Another Indian Mud Moray found at the side of a tidal river during an upset in water chemistry.  It is sharing the space with its prey - a Penaeid prawn, showing the direness of the situation.

References

• FishBase. Gymnothorax tile (Hamilton, 1822) – Freshwater Moray. Retrieved from https://www.fishbase.se/summary/Gymnothorax-tile.
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.

Mangrove Pipefish (Ichthyocampus carce)

Mangrove Pipefish (Ichthyocampus carce)

A large-sized Mangrove Pipefish compared to an usual-sized individual!

Family: Syngnathidae

Species Name: Ichthyocampus carce
Common Name(s): Mangrove Pipefish, Freshwater Pipefish, Indian Freshwater Pipefish

Presence in Singapore: Native
Habitat: Mangroves and estuaries, slow-moving to still water such as pools. Freshwater streams and rivers.
Conservation status: Vulnerable (Red Data Book 3)

One of the few estuarine Syngnathid (seahorses and pipefishes) that we can find in Singapore and the most readily seen too. It can be found in relative abundance during low tide, where it inhabits isolated pools and slow-moving creeks. Despite their numbers, their thin bodies and brown colouration makes them tough to spot. They can grow up to 15cm in length but are usually found at sizes half of that, adding on to the difficulty. 

For a fish with such a seemingly small mouth, they are voracious predators of small invertebrates and zooplankton, which they snake along the sediment or around mangrove roots to stalk.

Like all Syngnathids, the males raises the eggs. The male Mangrove Pipefish carries the eggs in a brood pouch found under the tail.

One out of several Mangrove Pipefish found in an isolated pool with many estuarine gobies.

References

• ​FishBase. Ichthyocampus carce (Hamilton, 1822) – Freshwater Pipefish. Retrieved from https://www.fishbase.se/summary/Ichthyocampus-carce.html.
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• Ong JXL & Tay JX (2024) Biodiversity Record: Fish fauna of a mangrove tide pool at Sungei Buloh. Nature in Singapore, 17: e2024056. DOI: 10.26107/NIS-2024-0056
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.

Milkfish (Chanos chanos)

Milkfish (Chanos chanos)

A school of Milkfish at Sungei Buloh Wetland Reserve's main bridge.

Family: Chanidae
Species Name: Chanos chanos
Common Name(s): Milkfish

Presence in Singapore: Native
Habitat: Coastal and offshore waters, often enters esutaries.
Conservation status: Least Concern (Red Data Book 3)

Although adults live offshore, Milkfish are known to frequently enter shallow coastal waters and estuaries, sometimes touching freshwater. They can be commonly seen in schools during the rising and high tide in habitats such as tidal rivers, where they sometimes mix with mullets. These are sizable fishes, growing to a maximum length of 1.8 meters but usually average out at a meter and are recognizable by their deeply forked tail.

Having a small mouth, Milkfish are omnivorous and feed on a variety of pelagic organisms such as zooplankton and fish larvae. They also feed near the bottom on benthic invertebrates, algae and even detritus. Milkfish themselves are important food fish for humans and are farmed as well. 

The Milkfish is the sole-living representative of the family Chanidae, which includes several extinct genera that existed during the Cretaceous. 

Adult Milkfish spawn in the sea, where the maturing juveniles swim back to coastal waters or even further upstream to grow. 

A small Milkfish following a school of mullets.

References

• FishBase. Chanos chanos (Fabricius, 1775) – Milkfish. Retrieved from https://www.fishbase.se/summary/chanos-chanos.
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.

Javanese Ricefish (Oryzias javanicus)

Javanese Ricefish (Oryzias javanicus)

A school of Javanese Ricefish at Pasir Ris Park's Mangrove Boardwalk (Photograph by: Lumin Ong)

Family: Adrianichthyidae
Species Name: Oryzias javanicus
Common Name(s): Javanese Ricefish

Presence in Singapore: Native
Habitat: Various brackish and freshwater habitats like mangrove swamps and canals.
Conservation status: Least Concern (Red Data Book 3)

A small but very adaptable fish commonly seen in not only our estuaries, but sometimes also in freshwater as well. The Javanese Ricefish can be found in schools of varying sizes and are recognizable by their guppy-like appearance. They have a distinct yellow ring around their tail which helps to separate them from other ricefish species found in the region.

Growing to a maximum size of 4.5cm, the Javanese Ricefish is mainly a micropredator of tiny crustaceans and protozoa but are known to consume detritus and algae too. 

The female carries her eggs outside her genital pore via filaments.

A Javanese Ricefish at Eagle Point during a rising tide.

References

• FishBase. Oryzias javanicus (Bleeker, 1854) – Javanese Ricefish. Retrieved from https://www.fishbase.se/summary/Oryzias-javanicus.html.
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.