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Archer
Fish Toxotes jaculatrix Siamese Archer Fish, Ikan Sumpit (Malay)  Archer
Fishes are famed for their ability to shoot down insects and small
creatures resting on foliage or mangrove roots. In fact, Toxotes
means "bowman" or "archer". Their flattened body
presents a narrow profile from above, so they can sneak up on their
prey. The bold black-and-white markings camouflage them in the sundappled
water under mangrove vegetation.
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| How
do they shoot? Archer Fishes are like submarine water pistols
and can spit out a strong and accurate jet of water. With their tongue
against the groove on the roof of their mouth, they form a tube, and
force water powerfully out by snapping shut their gills. To get a
good jet of water, the snout sticks out of the water, but the rest
of the fish remains underwater. They direct the jet of water with
the tip of their tongue. For accurate aim, they have large eyes located
very near the mouth, which give good binocular vision. Their eyes, however, do not automatically correct for refraction, and they have to learn how to do this. The position of least distortion is directly below the prey, and the fish soon learn that this is the best shooting spot. The fish can squirt up to 7 times in quick succession, and the jet can reach 2-3m, but they are accurate to only about 1-1.5m. Fish as small as 2-3cm long can already spit, but their jets reach only 10-20cm. |
 Photo from David Stone |
 Photo from John Palmer |
Once
the jet of water knocks down the titbit, the fish gulps it down in
its large deep upwardly directed mouth. If the blast doesn't knock
down the prey, sometimes the weight of the water on the wings causes
the insect to lose its grip and fall. Other ways to get their lunch: Archer Fishes, however, prefer to leap out of water to grab the prey in their jaws when it is close enough. When the leap fails, they may then resort to spitting. Archers usually swim in shooting parties. Often, several shoot at the same prey, and shoot relentlessly. When the prey finally falls, all rush to grab it. As the sharpshooter doesn't always get the prize, if the prey is within reach, the fish prefers to leap out of the water and grab it in its jaws. A prey in the mouth is worth two spat at! They can jump up to 30cm high. But Archer Fish don't just eat above-water prey. They also hunt small aquatic creatures and fishes, sometimes swimming in deeper water to catch these. |
Breeding: It is believed that only the juveniles are found in brackish water while the adults are more solitary and swim out to the coral reefs to breed. 20,000-150,000 eggs are laid. Only a few reach maturity in 1-2 years. Young fish have iridescent yellow patches on their upper body between the dark bands, which perhaps helps them to school together in the muddy waters. As they get older, patches disappear and the black bands get shorter and eventually only seen on the uppermost part of the body.
Role in the habitat: Found in brackish water in mangroves and estuaries and sometimes further inland in fresh water.
| Status and threats: Archer fish control populations of their prey. They are also food for others higher up on the food chain. Although Archers are fairly common, they are threatened by the destruction of mangroves and by collection for the pet trade. Two Southeast Asian species are collected for the aquarium fish trade. They are not bred in captivity. |
FISH
PATROL:
In Kew Gardens, Archer fishes are kept in ponds with tropical waterlilies to help keep down small insect pests and aphids! |
- Endangered Vertebrates of Singapore on the Singapore Science Centre website: Brief fact sheet, photo of Toxotes jaculatrix:
- Richard's Fish Tanks Page: fact sheet on distribution, how they shoot and other adaptations.
- Who Zoo website: fact sheet on features, habits including how they shoot and other adaptations, distribution, with drawing and links.
- South Australian Museum: fact sheet on features, habits.
- Sharpshooters
of the mangroves on Wetland Wonders on the Wetlands International-Asia
Pacific website: Updated 28 February 1999 - Volume 3 Issue 5: fact sheet
on features, habits.
- Hunting strategies in the Archer Fish (Toxotes chaterus) by Michael Pollirer and Ludwig Huber: exploring the reasons why Archer Fish prefer to jump for rather than shoot at prey.
- The Physics Classroom by Tom Henderson - Lesson 1: Scientific explanation of how the fish learns to compensate for refraction.
- Archer fish "The Sharpshooter" in the 1998 Animal Olympics by Discovery Channel Online: for more on how they spit.
- Among
the Mangroves by Adrian R. Tappin on Rainbowfish Online: info and
photos on all kinds of fishes found in Australian mangroves including
the Archers.
| To
buy these references & others, visit Nature's Niche |
- Peter K L Ng and N Sivasothi, "A Guide to the Mangroves of Singapore II: Animal Diversity", Singapore Science Centre, 1999 (p. 134: description, habits, habitat, photos).
- Dr J.D. Van Ramshorst (ed.), "The Complete Aquarium Encyclopedia of Tropical Freshwater Fish", Elsevier Publishing Projects, 1978 (p. 364-365: features, habits, description of shooting, photo).
- John Palmer (ed.), "Exploring the Secrets of Nature", Readers' Digest Association, 1994 (p. 194: description of shooting and jumping, photo).
- David Stone, "Biodiversity of Indonesia Tanah Air", Didier Millet, 1994.