Predators of Adult Fish

The food web in the aquatic environment is topped by hunters, fish that hunt and kill other fish. Fish are a good food in terms of nutrition but they have a major drawback — they are slippery customers and difficult to catch. The secret of success for piscivorous (fish-eating) fish is to get as close as possible to the intended prey without being detected before launching an attack.To enable these hunters to do this, they have adopted a variety of cunning strategies.

How do predatory fish avoid scaring their prey?

One way to get to within striking distance is to blend into the background and be very, very patient Wide-mouthed catfish (Chaca chaca) conceal themselves in the substrate, often with only their eyes betraying their presence, and then play a waiting game. If a small fish happens to stray too close, the catfish erupts out of its hiding place and engulfs its unfortunate prey. Leaf fish (Monocirmus polyacanthus) perform a similar trick. As their name suggests, they are masters of disguise. Resembling a fallen leaf, they bide their time among the vegetation until a fish makes its final mistake and approaches too close.

What are the main features of an ambush predator?

Predators that ambush their victims by speeding from concealment often share a common body plan: large head, long, tapered body, and fins set Ambush predators have a large amount of white, anaerobic, fast-twitch muscle, just like human sprinters. When it comes to making a quick start, these fish have no equal. Lastly, they have extremely large mouths, often lined with forbidding, backward-pointing teeth.This body design can be seen across a range of completely unrelated piscivores — pike cichlids (Crenicichla spp.), pike livebearers (Belonesox belizanus), and pike characins (Phago spp., Luaocharax spp., Hydrocinus spp.).

Although such fish rely mainly on prey fish swimming past their place of concealment, they also stalk their quarry, moving extremely stealthily, almost imperceptibly closer, with barely a ripple of their fins, until they come within range of their target.

Can fish stalk their prey?

Large nocturnal predators, including many members of the catfish family, stalk their prey in the dark Recent research has shown that the hunters follow the vortices left behind by a passing fish, approaching closer and closer until they can attack Other species rely on less subtle techniques; spotted catfish (Pimelodus pictus) chase their targets (usually any fish small enough to fit into their mouths) to exhaustion.

Do predators make good aquarium fish?

Maintaining piscivores in the home aquanum can be difficult for a variety of reasons. Many predators are strangely skittish and feil to settle. Furthermore, fish such as the pike livebearer are confirmed piscivores and need to be fed with live fish. Although this is perfectly natural behavior — predation is a fact of life for fishes — many fishkeepers may feel uncomfortable breeding guppies to feed to a predator If this is the case, the aquarist should think hard before acquiring such a fish.