Pelagic fish

A fish that lives in the water column rather than on or near the seabed. Pelagic species inhabit coastal waters, the open ocean, or both.

Pelagic zone: The part of a sea or lake that is neither the shore nor the bottom. Pelagic fish occupy this open-water habitat rather than the seabed.
Fish locomotion: The ways fish move through water using fins, body motion, or both. Pelagic fish use sustained swimming to forage and migrate through open water.
Pelagic fishing: Fishing directed at species that occupy the water column rather than the seabed. It targets pelagic fish with gear suited to open-water swimming and schooling.
Marine food web: The network of feeding relationships among organisms in marine ecosystems. Pelagic fish transfer energy from plankton and smaller fish to larger predators.
Epipelagic zone: The ocean layer from the surface to about 200 meters, where sunlight penetrates. Many pelagic fish feed or school in this sunlit layer.
Fish schooling: The coordinated swimming of fish in a group, often in a consistent direction and spacing. Schools can reduce individual risk and help pelagic fish find prey.
Purse seining: A fishing method that encircles a school with a net drawn closed at the bottom. It is widely used to catch schooling pelagic species.
Forage fish: Small schooling fish that serve as prey for larger fish, seabirds, and marine mammals. These pelagic species channel plankton production to higher predators.
Mesopelagic zone: The ocean layer, roughly 200 to 1,000 meters deep, with too little light for photosynthesis. Many pelagic species spend daylight hours at these depths.
Countershading: A coloration pattern with a darker upper surface and a lighter underside. This pattern makes pelagic fish less visible from above and below.

Linked from 19 pages