Ichthyology

Pelagic fish live in the pelagic zone of ocean or lake waters – being neither close to the bottom nor near the shore – in contrast with demersal fish, which do live on or near the bottom, and reef fish, which are associated with coral reefs.

In fishkeeping, suitable species of aquarium fish, plants and other organisms vary with the size, water chemistry and temperature of the aquarium.

Electroreception is the biological ability to perceive natural electrical stimuli.

Bait fish are small fish caught for use as bait to attract large predatory fish, particularly game fish.

Freshwater fish are those that spend some or all of their lives in fresh water, such as rivers and lakes, with a salinity of less than 0.

Squalene is a natural 30-carbon organic compound originally obtained for commercial purposes primarily from shark liver oil (hence its name, as Squalus is a genus of sharks), although plant sources (primarily vegetable oils) are now used as well, including amaranth seed, rice bran, wheat germ, and olives.

Spawn is the eggs and sperm released or deposited into water by aquatic animals.

FishBase is a global species database of fish species (specifically finfish).

The term shark attack is used to describe an attack on a human by a shark.

Ichthyoplankton (from Greek: ἰχθύς, ikhthus, "fish"; and πλαγκτός, planktos, "drifter") are the eggs and larvae of fish.

Ichthyology (from Greek: ἰχθύς, ikhthus, "fish"; and λόγος, logos, "study"), also known as fish science, is the branch of biology devoted to the study of fish.

A bait ball, or baitball, occurs when small fish swarm in a tightly packed spherical formation about a common centre.

Pahutoxin, formerly called ostracitoxin, is a neurotoxin present in the mucous secretions of boxfish (Ostraciidae) skin, while under stress.

Ichthyology uses several terms that are unique to the science.

This is a list of common fish names.

Forage fish, also called prey fish or bait fish, are small pelagic fish which are preyed on by larger predators for food.

Fish intelligence is ".

The prevailing type of fish locomotion is swimming in water.

Juvenile fish go through various stages between birth and adulthood.

Demersal fish live and feed on or near the bottom of seas or lakes (the demersal zone).

Bubble nests, also called foam nests, are created by some fish and frog species as floating masses of bubbles blown with an oral secretion, saliva bubbles, and occasionally aquatic plants, or an area for egg deposit attached at the bottom.

Fish anatomy is the study of the form or morphology of fishes.

Fish are very diverse animals and can be categorised in many ways.