Search results
Results from the WOW.Com Content Network
Fish born in different regions will show clear differences here. Studies of the commercial fishing industry in the United States show that the population of bluefin tuna in the North Atlantic is made up of fish hailing from both coasts. While the fish may live in close proximity out in the Atlantic, they return to their natal region to spawn.
The behavior of an amphibian hatchling, commonly referred to as a tadpole, is controlled by a few thousand neurons. [4] 99% of a Xenopus hatchling's first day after hatching is spent hanging from a thread of mucus secreted from near its mouth will eventually form; if it becomes detached from this thread, it will swim back and become reattached, usually within ten seconds. [4]
Potamodromous – fish whose migrations occur wholly within fresh water; Oceanodromous – fish that live and migrate wholly in the sea [5] [10] Although these classifications originated for fish, they can apply, in principle, to any aquatic organism. List of diadromous orders and families, and the number of known species: [9] [11]
A grizzly bear ambushing a jumping salmon during an annual salmon run. A salmon run is an annual fish migration event where many salmonid species, which are typically hatched in fresh water and live most of their adult life downstream in the ocean, swim back against the stream to the upper reaches of rivers to spawn on the gravel beds of small creeks.
Juvenile fish are marketed as food. Whitebait is a marketing term for the fry of fish, typically between 25 and 50 millimetres long. Such juvenile fish often travel together in schools along the coast, and move into estuaries and sometimes up rivers where they can be easily caught with fine meshed fishing nets.
The fertilized eggs float close to the surface, carried by the currents, and hatch in 15 days. Before hatching the eggs sink to the bottom. Before hatching the eggs sink to the bottom. For the next four to six months baby flounders float in the open ocean , sometimes hundreds of miles from the place the eggs were released and hatched.
In July, some mature individuals migrate back towards the sea, sometimes crossing wet grasslands at night to reach rivers that lead to the sea. Eel migrations out of their freshwater growth habitats from various parts of Europe, or through the Baltic Sea in the Danish straits, have been the basis of traditional fisheries with characteristic ...
Unlike invertebrates that use ciliated motion to move food, ostracoderms used their muscular pharynx to create a suction that pulled small and slow-moving prey into their mouths. The first fossil fish that were discovered were ostracoderms. The Swiss anatomist Louis Agassiz received some fossils of bony armored fish from Scotland in the 1830s ...