“Cupid, draw back your bow, and let your arrow go straight to my lover’s heart for me.” So sang R&B legend Sam Cooke. It’s a different tune in Shedd Aquarium’s Waters of the World Rivers gallery, where deadly accurate (and thankfully small) banded archerfish from the brackish mangrove estuaries of the Indo-Pacific and northern Australia spit down their insect prey with high-pressure “arrows” of water.
Adult archerfish almost always hit their prey on the first shot. (Or perhaps it’s the fact that the fish that are most successful in hunting reach adulthood.) They can knock a grasshopper, spider, or butterfly off a branch from as far as 5 feet away.
First, of course, the fish has to see its prey. In addition to having large eyes, the banded archerfish is unusual in having binocular vision. But it can also compensate for the refraction of light at the water’s surface as it takes aim. With its lips just breaking the surface, the fish presses its tongue against a narrow groove in the roof of its mouth, forming a thin, tubelike channel, and snaps shut its gill covers so that it spits a jet of water droplets under high pressure. The fish can adjust the force of the water to the size of its prey. Because banded archerfish often cluster in small groups near the surface, and competition is fierce, the successful hunter darts to the downed prey, reaching it within 50 milliseconds of it hitting the water.
Gallery aquarist Steve Ehrlich notes that an archerfish can even put out a lighted cigarette, like a tiny fire extinguisher, although you won’t see that sort of stunt at Shedd. If you’re lucky, however, you might be around at feeding time when Steve places small crickets on the exposed mangrove roots in the exhibit for the fish to shoot down.
Archerfish will also leap out of the water to grab low-hanging insects and nibble on aquatic vegetation.
We’ll admit that as far as Valentine’s Day goes, archerfish are more closely aligned with Sagittarius, the archer of Greek mythology, than the winged (and armed) Roman god of desire. In fact, the fish’s Latin name is a double reference to Sagittarius: The genus name, Toxotes, is Greek for archer or bowman, and jaculatrix, the species name, is based on the obscure English noun jaculate, or “thrower,” which is derived from the Latin verb jacere, to throw.
Alas, while banded archerfish are available in the pet trade, they do not love living in the typical home aquarium setup. They don’t transition well from hunting live food to taking flake food, nor do they lose the jumping habit.
So treat your sweetie to a Shedd visit (and take advantage of our buy-one-get-one-free offer this month) for the chance to see these small water archers in action. It’s enough to make Cupid quiver in envy.
Want to see an archerfish in action, check out this clip from ABC's Animals Action.
—Karen Furnweger, web editor