Fish migrationFish migration is mass relocation by fish from one area or body of water to another. Many types of fish migrate on a regular basis, on time scales ranging from daily to annually or longer, and over distances ranging from a few metres to thousands of kilometres. Such migrations are usually done for better feeding or to reproduce, but in other cases the reasons are unclear. Fish migrations involve movements of schools of fish on a scale and duration larger than those arising during normal daily activities.
Mesopelagic zoneThe mesopelagic zone (Greek μέσον, middle), also known as the middle pelagic or twilight zone, is the part of the pelagic zone that lies between the photic epipelagic and the aphotic bathypelagic zones. It is defined by light, and begins at the depth where only 1% of incident light reaches and ends where there is no light; the depths of this zone are between approximately 200 to 1,000 meters (~656 to 3,280 feet) below the ocean surface.
Fish stocksFish stocks are subpopulations of a particular species of fish, for which intrinsic parameters (growth, recruitment, mortality and fishing mortality) are traditionally regarded as the significant factors determining the stock's population dynamics, while extrinsic factors (immigration and emigration) are traditionally ignored. All species have geographic limits to their distribution, which are determined by their tolerance to environmental conditions, and their ability to compete successfully with other species.
LampriformesLampriformes 'læmprᵻfɔːrmiːz is an order of ray-finned fish. Members are collectively called lamprids (which is more properly used for the Lampridae) or lampriforms, and unite such open-ocean and partially deep-sea Teleostei as the crestfishes, oarfish, opahs, and ribbonfishes. A synonym for this order is Allotriognathi, while an often-seen, but apparently incorrect, spelling variant is Lampridiformes. They contain seven extant families which are generally small but highly distinct, and a mere 12 lampriform genera with some 20 species altogether are recognized.
Coral reef fishCoral reef fish are fish which live amongst or in close relation to coral reefs. Coral reefs form complex ecosystems with tremendous biodiversity. Among the myriad inhabitants, the fish stand out as colourful and interesting to watch. Hundreds of species can exist in a small area of a healthy reef, many of them hidden or well camouflaged. Reef fish have developed many ingenious specialisations adapted to survival on the reefs. Coral reefs occupy less than 1% of the surface area of the world oceans, but provide a home for 25% of all marine fish species.
Saltwater fishSaltwater fish, also called marine fish or sea fish, are fish that live in seawater. Saltwater fish can swim and live alone or in a large group called a school. Saltwater fish are very commonly kept in aquariums for entertainment. Many saltwater fish are also caught to be eaten, or grown in aquaculture. However, many fish species have been overfished and are otherwise threatened by marine pollution or ecological changes caused by climate change. Fishes that live in the ocean can be carnivores, herbivores, or omnivores.
StingrayStingrays are a group of sea rays, which are cartilaginous fish related to sharks. They are classified in the suborder Myliobatoidei of the order Myliobatiformes and consist of eight families: Hexatrygonidae (sixgill stingray), Plesiobatidae (deepwater stingray), Urolophidae (stingarees), Urotrygonidae (round rays), Dasyatidae (whiptail stingrays), Potamotrygonidae (river stingrays), Gymnuridae (butterfly rays) and Myliobatidae (eagle rays). There are about 220 known stingray species organized into 29 genera.
Neritic zoneThe neritic zone (or sublittoral zone) is the relatively shallow part of the ocean above the drop-off of the continental shelf, approximately in depth. From the point of view of marine biology it forms a relatively stable and well-illuminated environment for marine life, from plankton up to large fish and corals, while physical oceanography sees it as where the oceanic system interacts with the coast.
FinA fin is a thin component or appendage attached to a larger body or structure. Fins typically function as foils that produce lift or thrust, or provide the ability to steer or stabilize motion while traveling in water, air, or other fluids. Fins are also used to increase surface areas for heat transfer purposes, or simply as ornamentation. Fins first evolved on fish as a means of locomotion. Fish fins are used to generate thrust and control the subsequent motion.
Kuroshio CurrentThe Kuroshio Current, also known as the Black or Japan Current or the Black Stream, is a north-flowing, warm ocean current on the west side of the North Pacific Ocean basin. It was named for the deep blue appearance of its waters. Similar to the Gulf Stream in the North Atlantic, the Kuroshio is a powerful western boundary current that transports warm equatorial water poleward and forms the western limb of the North Pacific Subtropical Gyre. Off the East Coast of Japan, it merges with the Oyashio Current to form the North Pacific Current.